WTF are you talking about? He is building stuff that is already in service with the US military, he is literally copying others ideas so poorly that he is failing hard when the info to do this is already out there.
I'll be real, what probably happened to the fan blades is that on impact the case flexed a bit and they hit the side wall. I've seen it happen to several EDFs in the past. If it did suck something in, you can help to prevent that by putting the intake on the top instead of the bottom where it will eat dirt every time it lands.
Ah yes, my favourite non-military engineer, building non-autonomous, IR guided, non-loitering munitions / non-cruise missile / non-air-intercept drone / non-autonomous recon platform. Jesus at this point you are just building next gen autonomous drone. Also i belive that you have exact ideas what can be put into that free space.
I’ve been designing and building competitive RC planes for a couple years in SAE aero and here is my brain dump: 1. Thrust needs to be increased, EDFs are not known for their static/low speed thrust, especially those small ones. (EDIT: Now thinking about it, adding a folding propeller in the front would help increase thrust and reduce wiring weight since your batteries are in the front also) Make sure you have an adequate thrust to weight ratio. Decreasing takeoff weight is crucial since your wing area is a design constraint. Increase powertrain battery voltage if you can, you’ll have to sacrifice capacity to save weight though. 2. Use an analysis tool like XFLR5 instead of ecalc, it uses actual airfoil data and VLM to solve for lift, drag, and moment along CG. See how much lift you’re making at takeoff speeds near stall angle. Check CG also, it might be unstable (especially on launch 3) 3. Increase aft control surface size, they look pretty small and won’t do much at low speeds. The EDF should help, but looking at the video it’s not enough. The planes longitudinal inertia seems really high especially with the heavy batteries up front and large fuselage. 4. I believe you are close to/a little unstable in yaw because you don’t recover very fast at 13:11. You have almost equal stabilizing and destabilizing side area on the fuselage and the control surfaces don’t seem to help with that since they’re moving to control pitch and roll. Increase your aft side area, this will help you recover from a large sideslip which seems to be the biggest issue on takeoff at lower speeds. At a 90 degree sideslip on the 3rd attempt the plane seemed like it had no intention of recovering from it. This could be done by adding fixed fins that are not your control surfaces. You will also dutch roll during these thrown takeoffs if you dont have yaw damping. 5. Add ailerons because you have little roll authority at lower speeds. Roll authority increases if your control surfaces are further outward- those in the back aren’t gonna do much if you have a large lateral inertia from the wings, but this all depends on how heavy the wings are. Your plane rolled a lot during these takeoffs and didn’t seem to want to recover. Dihedral won’t solve this problem. Include a flap too for higher lift during takeoff. If you have any questions I’d be happy to answer in the reply comments or if you have a discord.
didnt know sae had a drone competition. I am the aero composite lead in my school's formula sae team. would have joined the drone one if my school had it
Imo I would agree with kyle points but I would give a try using some kind of launcher which would give much more speed at takeoff as first step just to make it launchable.
when starting with your hand, you can also give a small run-up (that is, run with a run-up) - this will add high-speed pressure + run with an angle of attack, that is, nose up, but not too much. Also, the launch should be done as high above the head as possible, so that the height above the ground is as high as possible, because after launch, the aircraft is likely to fly to the ground at the initial moment of time, it needs to have time to taxi from the ground - for this you need a margin in height for maneuver. Another wing - at subsonic speeds, it makes no sense to make a swept wing, as far as I know, the optimal wing shape is a straight leading edge - it will give the greatest aerodynamic quality - you can also play with wing profiles - Xfoil will help
As someone who builds a lot of RC planes, I’d recommend adding ailerons, and possibly flaps, to improve lift and control at lower speeds during takeoffs and landings. As you mentioned, the plane seems too heavy relative to the available thrust-using lightweight filaments would help a lot. Also, it’s unlikely you’ll be able to manually stabilize the plane quickly enough during takeoffs and landings, so I highly recommend adding a flight controller for automatic stabilization. Finally, it looks like the elevator authority might not be sufficient with just the vectored thrust setup. All that said, this plane looks absolutely stunning, and I can’t wait to see what you do with v2!
I don't know too much about this field but would it not be extremely hard to add control surfaces as well as the servos to control them when the end goal is for them to fold?
@@smellyboars4865 flaps would be a pain (and probably needed it if the wings are just bigger) but ailerons could added without too much extra complication... especially considering how complicated everything else on this is
Yes, it definitely needs ailerons, it has negative stability in the roll plane. A single micro servo would do that quite easily and cheaply. A rail/catapult launcher would certainly make getting it airborne a lot more consistent, and could be adjusted to give more/less speed on launch.
I disagree on the additional control surfaces, at least initially. Adding lightness is priority number 1, and ailerons aren’t really necessary when roll control can be carried out through X-.taik mixing. I’d instead move the wing up.
@@howlingwolven The X tail doesn't have enough of a control moment (force x distance) to be effective at low speed, maybe at Mach 1, but not at launch speeds. A micro servo is only about 2 grams in weight. Moving the wings up would certainly help.
As someone who also jumped into the RC hobby with 0 experience and decided to build an extremely complex model, this video is amazing. You just dialed everything to 11.
Not really. It's more akin to somebody trying to summit Mount Everest as their first climb with 100 kg of camping gear and no oxygen. Basically can't even get to base camp with all that crap.
@toolbaggers That is a terrible analogy and completely misses the point of engineering projects like this. The goal is to learn just as much as it is to succeed. It also significantly underestimates the complexities involved in designing systems like this. It's not a matter of "grab the right stuff and throw it together". Your comment makes it seem like he set himself up to fail, and that the plane not flying somehow means the project was a failure. I'm going on about this because reactions like yours are extremely frustrating to read, and they completely undermine the spirit of hobby engineering.
WTF are you talking about? He is building stuff that is already in service with the US military, he is literally copying others ideas so poorly that he is failing hard when the info to do this is already out there.
Correct me if I'm wrong, but Hatchet is meant to be initially launched via rocket with the EDF just keeping it in the air. As such, redesigning it to be hand-launched seems like a step in the wrong direction. I think a catapult is a better idea, as it can provide the higher launch speeds that are needed without having to deal with the complexities of rocket launches.
Or a magnetic linear rail launch system like Tom Stanton and others have built before. Smooth, consistent acceleration. Though that doesn't help the whole cruise missile vibe!
Given that he has never flown a radio control plane before this would be a step in the right direction. Slower flying means more forgiving and easier to launch/test. Once he can make the hand launch version work, then he can work on increasing the wing loading and going faster/autonomous
I agree, engineering a propulsive launch with discarding sabot-style engine mount might be a simpler solution than fundamental redesigns to allow for low speed launches, nearly an entirely separate vehicle mission set... Amazing work!
He could have also had someone else tow it with a rc (and a cradle with wheels to get it off the ground) like a glider and then ran the tests once it was already in the air.
Definitely reduce takeoff weight at least for early test flights. A rail launcher would be a game changer for getting you off the ground consistently with enough velocity to get enough lift out of the small wings. In addition, a rail launch would let you spin up your edf right before you launch. That way you are taking full advantage of your vectored thrust right as you leave the rail, when your control surfaces are going to really struggle giving you enough control authority.
ERAU Grad, changing the air frame before getting it airborne is going to kill his understanding of how it flies in its ideal flight configuration. He should be focused on getting it airborne first then worry about changing it IMO. Slingshot launch could help him dial in his v speeds without needing to redesign his aircraft.
This CAD work and prototyping is just awesome! That ducted fan exhaust has an expanding nozzle. But your air isn't supersonic -- it's not even compressed. So the exhaust will slow down and increase pressure through this nozzle, which means the nozzle will pull backward on the vehicle. You might want to switch to a converging (subsonic) nozzle. Also, for those jet vanes to work, you'd need to have the nozzle terminate right about where the vanes are. Also, isn't the center of lift on those vanes going to be through the 1/4 chord line? It looks to me that you may have the center of lift forward of the center of rotation. That's going to make the vane fight the servo whenever you try to reverse the control, which will increase hysteresis. It doesn't look like you have enough lift. Did you calculate your stall speed? That thing looks like it's maybe 4 kg? With 910 cm^2 of wing area, you'll need 430 Pa to hold it up, so you'll need about that in dynamic pressure (assuming your wing shape can do at least CL=1.0). At sea level that's 26 m/s, about 59 mph. An NFL quarterback would be hard pressed to throw that hard. Maybe you could use a big rubber band to launch it. Reducing weight 40% should reduce stall speed 20%. Dynamic pressure is 0.5*(air density)*(velocity)^2.
I was thinking rail launcher when your buddy was chucking it. I really think you need tail wings. Those 4 X-patten, or even 2 larger Y-pattern stabilizers, are not enough. I think you need the 2 larger Y-pattern rudders and 2 normal rear wings, then you'll home free. Stall and launch speeds will be much better. Some kind of carbon landing sliders might also be good. At least it when you are finally landing it, it will not risk tearing up the bottom. That's my 2 cents.
13:15 the way your friend is throwing it here is forcing the plane to pitch up. If he can hold it at COM and guide it into the air under the planes own power, you’ll be able to keep control. Alternatively maybe a rail like the V1 can help you eliminate variables here. Looking forward to seeing more!
No, no he can't. There isn't enough power and way too much weight. There is more than enough info out there that this dude should have figured this out before he failed like this.
I agree with your assessment that you have a yaw stability problem, first. Second, after you fix that, I agree with the other comments suggesting a catapult launch. Given the weight and designed launch mode, the hand launch simply isn't giving you enough velocity "off the rail". You may need a much larger wing to start with if you want to try that, but that carries more weight, more drag, and will again require you to add more yaw stability. Perhaps some longitudinal vanes to simulate more yaw control can help get you in the right direction. I'd also ask - Have you done any CFD to see if the wings are producing any turbulence that may be masking those small control surfaces? Especially at the high AoA you're probably expecting, that airflow may be nasty. If the air is clean enough, have you run the numbers to see if they're imparting enough lift/torque for all three control axes (concurrently, when the controls are blended) at whatever airspeed you can achieve with your friend's arm?
1. Take off weight is too large, well, at least for the wing area you have chosen which is pretty much fixed if they are going to fold out of the fuselage eventually. 2. CG and wing placement seem to be mismatched, dangle it on a string from the mean chord, quarter chord point as a sanity check. 3. Control surfaces are too small for realistically any control during takeoff, and the fact you do not have ailerons would mean that they would need increasing in size compared to a normal set. For roll control matching ref area isn't sufficient as the moments are what counts, that close to the fuselage the moment will be tiny. 4. I'm unsure about the thrust vectoring, there is so much vorticity coming from that ducted fan that redirecting that flow is probably doing nothing apart from obstructing it, which leads me to the final point.. 5. I don't think there is any thrust being made tbh. Compare just holding the plane at full throttle to what the fan is expected to produce. Really cool project, I hope you can make it fly!
Pretty good points, I was also going to point out the thrust vectoring and thrust issues, I feel that the thrust vectoring needs to be eliminated, and the inlet needs a big redesign to let a lot more are in and directing it accordingly, I would provably go with an all around inlet or 4 inlets similar to that of a cruise missile, but nonetheless it needs a lot of air going in just because its fan propulsion, there is no pressure differential created by combustion and the air needs to enter as easily as it can, that design could hinder the air flow.
My thoughts exactly aswell, i'd argue that he could make it a biplan to double the wing area but even that may not be enough, and comes with additional drawbacks.
Yes point 5 seemed almost obvious, but I could be mistaken. With enough trust I would expect it to at least fly a few meters even with all the other points being an issue as well. I would've expected a thrust test inside. :)
The slingshot rail launcher is a good idea, I'd hook at the front, as without momentum at the front, the "pusher" is basically flipping the rear around, hopefully yanking it on a rail from the front will have it up to speed so the pusher isn't "end-arounding" it. Good luck!
You should try a bungee launch. It is much faster and more predictable than a hand launch, especially with a new plane. Also before you risk your complex delicate powered drone, I suggest you create a simple unpowered model from a cardboard tube that is appropriately weighted and winged to perform the same as the real thing and try launching that as a glider. If it wont glide, at least a little then adjust things until it does.
Some suggestions. More foam, less plastic. Foam wings. Ideally make the whole fuselage out of foam halves with pockets for electronics and lightening. Two fins, upward, V-tail, deploy them during flight so they don't interfere with booster. Catapult launch. Fins only need a small control surface, large stationary fins stabilize. I think the little fins in your prop wash are more harmful then helpful. Planes usually use vectoring cones.
Put it on a vertical test stand and measure thrust. I don't think you have NEARLY enough. It should be able to take off from your unlucky friend's hand.
I think the intake under the rear is also causing it to pitch up by creating a vacuum under the rear. Also think it 10 year old could come up with a better designed plane. So there’s that.
Just found this channel and I LOVE it! My 2c... Original design is like a cruise missile, which is typically launched at high speed - over 500 mph. Since you probably want to launch at closer to 7% of that for a hand launch, you need to make this like a small slow airplane. Control surfaces must be much much larger. Like 10 times the size for stability and authority at low speed, maybe bigger. And just do two on the top. No need for 2 little ones underneath. Wings also probably need to be larger - need to get that wing loading (lift/sq m) down. Weight is one way, but also more wing area. Also, no swept leading edge. Make it straight. How did you choose your airfoil cross section? You need more thrust. I bet if you put a scoop on the bottom a la F-16 (Or better yet, on the top like a Cirrus Vision Jet which also has a V tail) and got some ram air action going, rather than just suction, your CFM through the fan would go way way up. Finally, consider CG vs center of lift. You want your CG forward of CL but by how much? Moving CG back closer to CL can reduce required lift, but if you go too far you become too unstable. Go too far forward and you nose dive!
I am by no means an aerospace engineer, just a hobbyist drone/rc plane pilot. Here are my 2 cents: these first launch attempts look very similar to that I've experienced with my first rc plane (zohd nano talon). The problem with such planes is that they have a relatively high wing loading and are pretty hard to hand launch. I crashed my plane around 20 times before I figured out that you need to give it *much* more kick on the launch. Because of that I decided to bungee launch it. With bungee launcher it took off easily on the first try. My bungee setup consisted of 10 feet of rope attached to 10 feet of elastic band, the part with elastic band is attached to the hook on the ground. The other side with the rope has a loop which is attached to a hook mounted to the airplane. The hook should be mounted on the bottom of fuselage a bit forward of aircraft CG. Thanks for the great video. Best wishes from Ukraine.
How heavy is that thing? It looks like it weighs about 2x too much to hand launch. EDFs have basically no static thrust so the rail launch idea is definitely a good one but its a lot of time and effort when you need to focus on getting the characteristics of the airframe down first. I'd build a super light one just to test the advanced control system you are using. Maybe a foam board tube with a light 3d printed nose cone combined with moving the wings backward so you can use your existing edf location and power unit. Im biased as foam board is my bread and butter go to material for model planes. Also are you printing the plane out of any foaming light weight materials? I think they have just about everything in a LW version for RC planes nowadays. If you need that payload weight to stay the same you can only take so much weight out of the structure while keeping it in that soze and form factor. If it were me, I would shoot for something about 30% to 50% larger while trying to keep the weight of the structure relatively the same. I would also do a pusher prop on a thrust vectoring base along with ailerons for controls. If you want to keep the wings light and simple canards can handle the roll and add a lot more pitch control. Hope this helps! If you want to have a more in depth conversation let me know. I'll hop on the RC testflight discord.
A couple thoughts I had (although I don't do a lot of hobby drone stuff, I do work in aerospace) 1. 3d printed parts are probably not great for takeoff weight. It makes sense to use them for the aero surfaces where you need complex shapes, but you could probably cut down on their use in other places. The ball turret in particular strikes me as something that adds a lot of weight for something that still can't get a stable launch. Until you can get the prototype to reliably launch, maybe replace that and use a mass simulator to figure out what your mass budget for that payload is. 2. The inlet for the ducted fan looks like it's going to induce a pitch up moment that will vary with thrust, if possible, try replacing that with symmetric inlets so that you have more balanced aero forces. Also, having the inlet along the body like that makes me worry about losing thrust in high AoA situations, but at low speed, that's probably not as much of an issue. 3. I like the design of the control surfaces connected to thrust vector control vanes, but I worry about your proposed Y-tail idea. Non-symmetrical external control surfaces coupled to symmetrical internal control surfaces are going to require some complex control laws.
I can't speak for what filament he used but there are multiple 3d printing filaments out there designed for model aircraft - I'm assuming he used one of those filaments (?) I could be completely wrong, though.
The second I saw the first launch attempt, I thought in order: "too heavy" and "hmm maybe a bungee launcher would work. Seems you're on top of things and don't need my input. I'm excited to see what you come up with. My credentials are that I once duct taped a rock to a plane to balance the cg, and it flew great.
I might consider a weighted test article to hash out launch and glide ratio. Same weight layout and construction just without all the electronics. Inherently unstable works for fighter jets but your drone should be able to track mostly straight and glide even a little bit without input. This will also allow you to adjust CG location to determine balanced flight profile.
Some thoughts: 1. Are Center of lift/Center of gravity at the right spot? 2. Is the air inlet sufficient enough to generate enough thrust? Look at pictures of older Tomahawk cruise missiles. They had some kind of duct sticking out below for good air intake. 3. Is the thrust even enough for the over all weight? From the video it seems quite a lot of weight in the front. 4. The steering rudders might be a bit small to give enough directional authority?
I feel like with a set of canards (moveable or not) and a better inlet (or any way to produce more thrust), most of the issues could be fixed but that's just my guess, I'm no expert after all
If you get yourself some 3030 T slot aluminum you can easily put together a launcher for the drone using bunje cords. Im currently working on a long range survey drone, one main part is a launcher! You can also use compressed air to launch or even a magnetic rail but bunje or large rubber banding would do the trick nicely.
I think it needs to pass a glide test before you try powered flight. Make sure you've got the CG far enough forward to be stable and that the tail has enough downward pitch authority to keep the nose up.
Make the entire rear fin section magnetically detachable and use pogo pins to provide it power back there. Buy a compound bow and use that to get it up to launch speed; could probably make a stand utilize a garage door sensor to activate the full throttle condition to prevent any false launch events. I would also magnetically attach the wings as well if it remains fixed winged. Probably could add a simple parachute for free fall conditions as well.
Regarding your thoughts: 1. Yeah, your wing loading seems too high, especially considering you don't have highly cambered wings or flaps. You don't share numbers but for reference, a wing loading of 3.5 kg/m^3 will give a flight speed of 20mph at a coefficient of lift of 0.7. Printing your wings out of foaming filament can reduce their weight by like 40%, though you'd also want to incorporate a carbon spar. 2. Larger tail is necessary, but remember it doesn't all have to be all-moving control surfaces. If you want to experiment with stability margin, you could add a passive tail and reduce its size with progressive testing. 3. I agree rail launch with bungee is the safest way to get this thing up.
You might want to consider adding a scoop inlet for the edc, because it might be causing a low pressure zone and dragging the tail down. Might also protect the bottom fins and if printed in tpu could be flexible enough to absorb impact. Really freaking cool project man.
This is amazing dude. You casually made a Shahed-101. Looks like you learned why they use rocket assist take off. You also need a propeller about 3 times this size.
you can try adding foam on the belly to take the brunt of the landing, it also raises the planes height on the ground keeping you control surfaces safe. making it a y tail is good option, but would first run some CFD to analyze the plane's performance in various speeds. cool video, cant wait to see it autonomous( pixhawk ftw)
In thrust we trust bruh. I think those TVC vanes are trashing your thrust. Obviously weight reduction is great but stick a flow meter behind the thing and see what’s up before you go tearing it apart.
12:30 Looks possibly tails heavy but for sure the thrust isn't enough for hand launch. Ideally you'd want the EDF to almost support the "plane"'s weight. Not sure how much roll control you have, you may want more dihedral especially for Mk. I.
I wonder, why a swept back wing design? Swept back wings are worse than straight wings as low speed lift goes, also they have less than ideal stall characteristics Also those control surfaces might be still a bit too small but im not sure
Another thing, which airfoil are you using? I'd suggest to calculate a rough Reynolds number you'll be operating at and use an airfoil with a lower efficiency but better stall characteristics at first, then maybe move to a more efficient airfoil
The two things I'd suggest. Reducing weight is only a band aid. Figure out your V2 climb speed and design a catapult system that can rapidly accelerate the vehicle to that at a desirable angle and in a more stable way. The second thing is I'd suggest a more traditional rear stabilizer setup. There's a reason pretty much all aircraft have the vertical and horizontal stab planes rather than a rocket style configuration. Good luck and love what you're doing.
I would recommend building a model as similar as possible out of dollar tree foamboard. It is important that you get the CG right, normally about 1/4 chord or slightly forward works great. Testing a foamboard model would allow you to have the lightweight model you need for takeoff and hand launching while also allowing you to gain an understanding where you are lacking in stability. It may not hurt to try and throw your model in XFLR5 without the fuselage and run a stability analysis with your current cg location and such to ensure your model is statically and dynamaically stable. This will also allow you to quickly change your model in software and give you a good place to start with real world testing. I do not recomend sweep for a model like this because it is not going fast enough for it to consider compressible factors. The things I recomended should give you a good starting point and understanding, giving you more time to come up with possibly more thrust for hand launching or bunge launching methods.
i think a rial launcher would probably be the best idea. that would get you in the air easier and with a more repeatable method. I think this is my first video of this series so i apologise if this has already been checked but have you done any thrust tests for that ducted fan? i would have expected something like that to at least pick up a bit of speed after a hand launch but it doesn't look like there is a whole lot of thrust coming from that. i do look forward to the next video and i will have to go back and watch the previous videos.
Honestly, with that endoframe- skip the intake duct and let the edf breathe, just open frame it without the intake. While the intake might be fine at speed, all of the airflow at takeoff is coming from the fan/ vacuum cleaner lol.
After reducing take off weight, you could try diffrent types of launch, you could make some kind of catapult/slingshot/crossbow, the already mentioned rocket booster, or an aerial launch with a bigger craft, maybe not an aircraft but a drone that can lift it up enough to gain some speed
I really love the concept, so much room for even more potential. Regarding the wing surface area issue, have you ruled out all oldschool methods ? Particularly fabric skins? I imagined based on the earlier 2 part design (that had a high stall speed) but fabric or similarly malleable material stretching to form top & bottom skins. Allows a better airfoil profile, since its always landing like a convential plane and won't need to fold themselves back up until its on the ground, you could add some form of stringers for rigidity? Biggest restriction would be either end of speed envelope inducing turbulent flow over wing surfaces, flutter could run into immediate damage or failure if it's not super tight. 🤔 just an idea to brainstorm
@ if you’re speaking about my comment, I think I had an unstable internet connection and so it posted my comment twice. I’ll delete one to eliminate the confusion.
Ooh I like this idea. In air deployment sounds cool. Although, given the use case which he outlined, it should still have the ability to hover at a constant altitude to track the rocket launch, so achieving stability at low speed is of paramount importance. But wait, how does he plan to hover again with TVC EDF firing at the rear and fixed wing?
Maybe you could put a solid rocket booster and get it into the air vertically and program the engine to start when the rocket motor exhausts self ejects itself. At least you’ll be able to test the gliding ratio before impailing the ground. I LOVE LOVE IT!! keep up the hard work very impressive.
It would be hard to make kinda but a slingshot could be a solid launch method, I’ve seen them used before and are quite good at getting them gently up to speed easily. Also an acrylic covering over the camera turret that matches up with the fuselage tube might help protect it better
I love your use of common techniques like 3D printing and common motors to build things like this, its really unique and most things like this are behind military walls
Seriously impressive. I applaud your approach of reducing risk where you can for initial testing. Too many people try to do too much too early, which usually results in multiple failures. Have yuo had any problems finding suitable test ranges? Launch attempts 1 & 2 - Hand launching probably gives you a takeoff speed too low to support flight, even for this wing set. Also, the takeoff angle of attack looks far too great, which probably resulted in stalling the wings. In an effort to eliminate those variables, you might consider using a track laucher with bungee cords for the initial takeoff impulse force.
Hi, very nice design. I think you should use the extra space you have obtained with the folding wing compartment to add new batteries. What you want to achieve in the aerodynamic profile is to lock you tail at take off, add weight to the rear (batteries), enlarge you thin like a plane profile or even evolve from the X design to something able to produce the stability you need. You could also work on the lack of thrust you'd need to take off as a rocket :p
Firstly, I love this project it's cool as ...... On the constructive side I think your static thrust is to low for a hand launch, some options to solve that 1. the rail launch system has merit with the understanding that failure to achieve control will result in massive damage. 2. radically increase the power of the EDF and add an intake scoop to increase the efficiency of the EDF. 3. given your experience with rocketry build a fall away laugh booster that will give you both speed and altitude, the gentleman that taught me R/C flying always said, when trying something new "always fly three mistakes high" simple advise that has saved me many airframes (alas not all of them). I wish you success and I look forward to seeing your next project. Cheers from NZ
i am certain this man builds a missile and then sits and thinks for like 30 minutes about how to make it seem like its for amateur rocketry(i would do the same)
also: i would make it a stealthier cross section and put the inlet on the top.....ermmm i mean make it a lifting body and put the inlet on top to avoid FOD
Insane engineering right here, im barely getting to grips with blender at the moment would love to get into the electronics side of drone making , flew a few fpvs for a while and got pretty good but never built, also i print a lot 😃. Nice content man 👍
Some suggestions for your design. 1. Find and use a lightweight filament for this print. 2. Find and use some flight stability software. 3. Refine the inlet for the duct engine. I would add three duct inlets. One on the top and two on the side. 4. Increase the size of the wings to help with lift. 5. Move the wings to the aircraft's top to help with stability. 6. Rework the electronics so the center of gravity is just under the wings. 7. Remove all unnecessary equipment and only put what is needed to fly the drone. 8. Increase the size of your control surfaces. I hope these suggestions help.
Loved the video! I'm an Aerospace Engineer and I recently jumped head-first into a similar-ish project without any sort of RC experience. My system is purely meant for relaxing FPV flights, but I think I have a lot of useful insights as I encountered pretty much everything you did in this video. First of all, for RC planes, getting off the ground is the single biggest hurdle. Your mass right now is excessively high. Generating lift is proportional to velocity squared. So at low to no velocity, you reducing weight isn't just beneficial, it's a requirement. Then, I believe the choice of an EDF is a major mismatch with what you're trying to accomplish. I know, it looks really cool (trust me, I also started with an EDF), but their thrust at low speeds is really poor and in general, thrust is limited by their small diameter. As such, I would instead opt to swap the engine out for a propeller in a pusher configuration. This will bring you much more thrust due to the larger diameter prop you can use, and it will also easily double or tripple your flight time since propellers are far more efficient than EDFs. Rocket launches take some time to set up, so if you want to monitor the entire process, having some margin on your flight time will be much appreciated. Unfortunately, the addition of a propeller will make your vision of a rocket-launched plane very difficult. It's a conflict of requirements, and you might have to make concessions. It might be worth employing a proper System Engineering approach and noting down your principle requirements and order them in terms of their importantce. Noting key and killer requirements will make the system a lot more functional in the end. IMPORTANT NOTE: There is a high likelihood that a rocket-launched plane like this is very much illegal to build and operate. (Hobby) Rockets are legal because they generally only go up. As soon as you aim to transfer to horizontal flight and actively steer them, you are building a cruise missile! Finally, for your control surfaces, I would generally ditch the thrust-vaning control. Its addition to controllability on top of the main fins is likely negligible.
i was working with the Mirach series (targets) and they're very similar to the design you're looking for, in my opinion try put on a charge for the starting propulsion for short takeoff (with a tilted angle) or as you said a rail catapult, but i think you can improve the design changing the air intake and putting it on the top (or bottom) of the model in order to increase the aerodynamic suction angle and don't lose stability due to the small mass of the plane. you need to have an incidence for takeoff for this kind of design. Tbh cool idea, you can create a simpler underwater version with the design you made, if you put a fixed wing and some radars below (i was looking into make a similar models myself but require too much time for design of the wing nozzle etc)
I have some experience in hand launching RC planes. When I just started the biggest mistake I made (and I can see you make it as well) was to through the plane upwards. This makes the plane immediately stall. Even though it is counter intuitive you should through the plane slightly downwards (to a imaginary point about 10 meters or 30 feet in front of you) this way the plane will have enough speed to fly or it will just land without (or the least amount of) damage.
@@eriknulty6392 No, if the system is so screwed that you can't hand launch it then he probably isn't going to be able to hand fly it either. And spamming the same comment over and over again doesn't make it a better idea.
@@thomgizziz thats where you are wrong, that heavy bird with tiny control surfaces will fly great (AT HIGH SPEEDS). but going 4 mph you may as well just throw a brick. I do know a thing or 3 about building and flying scale planes, been doing it for 25+ years. but at that curb weight it wont fly until MIN. 20mph and thats probably even still pushing stall speed. she is a 50+ bird.
For hand launching try a wing tip launch. Hold it by the wing and spin and then release. Don't need as much strength that way. I am worried about the lack of control surfaces on the wings making it harder to control at low thrust. Another test is to empty out all the weight and see if you can get it to just glide. I can't wait to see the changes you make to get Hatchet in the air. Best of luck
Maybe print a Titan Falcon and get a FPV headset cheap plus IR video? No need to innovate when the solution is ready to print 😊 See YT videos, some militaries print them themselves to get cheap surveillance drones
@@TackshooterOG well, the Falcon gives you 300km range. But if you want cooler, how about the VTOL Titan Cobra? I actually just ordered parts for China for that one with FPV googles. Got them real cheap, like 60% off AliExpress since I lived in China and can buy it directly there. Still even with AliExpress parts, it's a damn cool morphing VTOL to Airplane
I see two big problems. The thrust from your impeller is too low. Not only because it is a fairly inexpensive impeller but also because electrical impellers build up little static pressure in the impeller and the diameter behind the impeller is smaller than the impeller itself. I also think your center of gravity is too far back. For further experiments I would get away from the the thrustvector, use a better impeller and first build a traditional aircrafttail with larger control surfaces, in order to have a better chance of being able to handle any strange flight characteristics better. Of course, a lighter aircraft always helps and could be successful when paird with a stronger impeller. If you want to achieve a good result, please only trust well-known manufacturers when it comes to thrust Statements. Hope that helps.😊
You think his center of gravity is too far back when it was nose diving into the ground... really? You think you are helping? Your nonsense about "impellers" is even worse.
Your engineering skills are very impressive. nice design. Makes sense considering your job. I agree with oth sentiment of other comments, way faster launch, way more thrust (more battery voltage?) might get you in the air without too many mods. Bunje cords on a guide rail launcher would be cheap and easy to make.
Reducing the weight will definitely make launching easier. You need to prove out the airframe design, then incrementally add weight to make sure it can still launch and have stable flight and good stall characteristics (which helps with landing too) I’ve done bungee launches where I attach surgical tubing to a stake in the ground. Keep the airplane and launch as simple as possible, then build up from there. It does seem to be that the tail is a bit small as well. Vtails (or an x tail in your case) tend to have a harder time providing yaw stability.
Not experienced, but I flew an RC plane/glider thing that had collapsible blades. This could be used to launch it, they have good static pressure. The EDF fan doesn't seem to be doing anything at launch speeds. I think also the control surfaces don't do anything at low speeds. For initial testing, I would install some mesh around the intake port and some cage wire thing around the control surfaces.
Very cool and ambitious project! Completely new desings are expected to end up in aerodynamics hell so hang in there! You should consider collaboration with another youtuber like Think Flight on this. He has experience designing and building winged drones so he might have some valuable input! In the meantime here are some ideas: 1) Push the center of mass forward, probably a lot. The aerodynamic center doesn't have enough leverage to keep the thing prograde. 2) Add ailerons on the wings for roll: Control authority far from the center of mass is a big yes. 3) I like the bigger top fins idea but a more traditional design might be more in order here for better control separation and whatnot. Rotate the back 45 degrees, add one big rudder fin on top and a bigger set of horizontal fins or even wings that can take over roll as well if big enough (they can also be set upside down for negative lift if you end up pushing the center of mass way forward and it ends up front-heavy). 4) Push or rotate the wings up to get a dihedral effect. Right now is looks like you get the opposite effect which actually gives the drone the tendency to go upside down. Good luck! Subscribing for this!
All ideas does sound legit. I have flown aircraft that was unlaunchable from they landing gears using a launcher, but I would suggest finding a friend with a drone to launch it from high altitude, but I understand if thats not an option. Further I'd suggest doing a test model, basically the same thing with a prop, because the Edfs are often way worse for slow speed scenarios.aybe getting a simple prop Infront or aft would be a good test bed, that would also take away the need for a launcher. Good luck and thank you for the video!
I would either use a bungee launch. I dont think you even need a rail. Stake one end in the ground and attach a hook just forward of the center of lift. The other open is to build a drop plane. I know this can create another set of issues, but something like the FT Guinea Pig (cargo plane) from flitetest is very cheap and fast build. I've used it a few times when I need a quick drop plane for stuff in the past. Cool video and Good Luck
Great wildly ambitious project. 2question/suggestions: 1: What is the stall speed? - can your helper throw the vehicle (or anything) to that speed? 2: thrust? From the very limited view it looks like it is frankly insignificant relative to the mass of the vehicle. It is obviously unable to visually accelerate the vehicle in the first 1-2 seconds. Your idea of reducing total mass is good. But I’m thinking you need to maybe triple the thrust! Or how about rocket assistance for 5-10 seconds? Good luck
hay there Lafayette Systems, wanted to suggest a little bit of an improvement. I would suggest that rather than having a inline inlet for the air, you put in a sort of scope or something which pushes the air into the engine from the front as i believe that the reason you stall is that you can't produce enough thrust to get off the ground with the air not getting feed in the engine. I would also suggest having some holes going around the engine just incase too much air gets traped infront of the fanblades. I hope this helps and wish you best of luck creating such an ausome program.
You can attach an assisted launch booster at the bottom of the drone, it should give it enough thrust in the launch stage to reach cruising speed. The current fan is also most likely too small to propel something of this size, the drone has the features of a cruise missile, you might need to increase wing span to get allow the drone to glide better, this can also reduce your excessive yaw rotation during launch.
This thing is rad i love the idea I would consider building a launch catapult for these test launches you could rig one up pretty simple with some aluminum rail and surgical tubing and that could help make your test launches more consistent. The drone itself is pretty awesome though it reminds me of the US made Switchblade drones except i dont think those use ducted fans.
I build some RC airplanes I would improve these things : 1. make either a more conventional tail or V-tail (you can still make it fully movable if you want) and with much larger surface area (by eye I would say 3-4x bigger). 2. get a higher speed launching mechanism as you said. Some ideas you didnt mention are launching it from a stationary quadcopter in the air or from the back of a moving vehicule.
I think you should definitely try the rail launcher. I would definitely remove the complicated servo portion from the wings and just make them spring loaded and retaned by a rubber band that can be cut with some nichrome wire heating up around it or something. That would remove alot of weight. The servos are cool but I dont see a need to retract the wings.
One thing that might help with weight is replacing the printed body with a carbon fiber tube with a similar inner diameter (if available) might be able to cut a little weight off. Other than that I think that increasing the takeoff speed in addition to the weight saving measures you mentioned should help considerably.
I just imagine some guy in the CIA building taking out a cigarette every time one of these videos is posted.
😂 indeeed
Russian or ukraine maybe
Learning is winning
cigarette
coffe
e're we go boi
WTF are you talking about? He is building stuff that is already in service with the US military, he is literally copying others ideas so poorly that he is failing hard when the info to do this is already out there.
9:51 "in terms of fan blades... we have no fan blades" 😭😭😭
you two collabing would go CRAZY
@BPSspace >>> Oh, are you familiar with rocketry?
😉 🤭
You should really do a collab and see what would come out of it
Maybe something like a reusable mini booster or something like that❤
I'll be real, what probably happened to the fan blades is that on impact the case flexed a bit and they hit the side wall.
I've seen it happen to several EDFs in the past.
If it did suck something in, you can help to prevent that by putting the intake on the top instead of the bottom where it will eat dirt every time it lands.
aa
Ah yes, my favourite non-military engineer, building non-autonomous, IR guided, non-loitering munitions / non-cruise missile / non-air-intercept drone / non-autonomous recon platform.
Jesus at this point you are just building next gen autonomous drone.
Also i belive that you have exact ideas what can be put into that free space.
Then he will sell it to Ukraine and earn a ton of money
candy, right?
@@SpongeBob-xh8ir ukraine lol
@@DC_DC_DC_DC yep, kacap killer candies
@@SpongeBob-xh8ir Almost all of the equipment is given not sold, they have basically no money.
I’ve been designing and building competitive RC planes for a couple years in SAE aero and here is my brain dump:
1. Thrust needs to be increased, EDFs are not known for their static/low speed thrust, especially those small ones. (EDIT: Now thinking about it, adding a folding propeller in the front would help increase thrust and reduce wiring weight since your batteries are in the front also) Make sure you have an adequate thrust to weight ratio. Decreasing takeoff weight is crucial since your wing area is a design constraint. Increase powertrain battery voltage if you can, you’ll have to sacrifice capacity to save weight though.
2. Use an analysis tool like XFLR5 instead of ecalc, it uses actual airfoil data and VLM to solve for lift, drag, and moment along CG. See how much lift you’re making at takeoff speeds near stall angle. Check CG also, it might be unstable (especially on launch 3)
3. Increase aft control surface size, they look pretty small and won’t do much at low speeds. The EDF should help, but looking at the video it’s not enough. The planes longitudinal inertia seems really high especially with the heavy batteries up front and large fuselage.
4. I believe you are close to/a little unstable in yaw because you don’t recover very fast at 13:11. You have almost equal stabilizing and destabilizing side area on the fuselage and the control surfaces don’t seem to help with that since they’re moving to control pitch and roll. Increase your aft side area, this will help you recover from a large sideslip which seems to be the biggest issue on takeoff at lower speeds. At a 90 degree sideslip on the 3rd attempt the plane seemed like it had no intention of recovering from it. This could be done by adding fixed fins that are not your control surfaces. You will also dutch roll during these thrown takeoffs if you dont have yaw damping.
5. Add ailerons because you have little roll authority at lower speeds. Roll authority increases if your control surfaces are further outward- those in the back aren’t gonna do much if you have a large lateral inertia from the wings, but this all depends on how heavy the wings are. Your plane rolled a lot during these takeoffs and didn’t seem to want to recover. Dihedral won’t solve this problem. Include a flap too for higher lift during takeoff.
If you have any questions I’d be happy to answer in the reply comments or if you have a discord.
didnt know sae had a drone competition. I am the aero composite lead in my school's formula sae team. would have joined the drone one if my school had it
Imo I would agree with kyle points but I would give a try using some kind of launcher which would give much more speed at takeoff as first step just to make it launchable.
Wonderful and massively underrated comment.
XFLR5 and OpenVSP
when starting with your hand, you can also give a small run-up (that is, run with a run-up) - this will add high-speed pressure + run with an angle of attack, that is, nose up, but not too much. Also, the launch should be done as high above the head as possible, so that the height above the ground is as high as possible, because after launch, the aircraft is likely to fly to the ground at the initial moment of time, it needs to have time to taxi from the ground - for this you need a margin in height for maneuver. Another wing - at subsonic speeds, it makes no sense to make a swept wing, as far as I know, the optimal wing shape is a straight leading edge - it will give the greatest aerodynamic quality - you can also play with wing profiles - Xfoil will help
As someone who builds a lot of RC planes, I’d recommend adding ailerons, and possibly flaps, to improve lift and control at lower speeds during takeoffs and landings. As you mentioned, the plane seems too heavy relative to the available thrust-using lightweight filaments would help a lot. Also, it’s unlikely you’ll be able to manually stabilize the plane quickly enough during takeoffs and landings, so I highly recommend adding a flight controller for automatic stabilization. Finally, it looks like the elevator authority might not be sufficient with just the vectored thrust setup.
All that said, this plane looks absolutely stunning, and I can’t wait to see what you do with v2!
I don't know too much about this field but would it not be extremely hard to add control surfaces as well as the servos to control them when the end goal is for them to fold?
@@smellyboars4865 flaps would be a pain (and probably needed it if the wings are just bigger) but ailerons could added without too much extra complication... especially considering how complicated everything else on this is
Yes, it definitely needs ailerons, it has negative stability in the roll plane. A single micro servo would do that quite easily and cheaply. A rail/catapult launcher would certainly make getting it airborne a lot more consistent, and could be adjusted to give more/less speed on launch.
I disagree on the additional control surfaces, at least initially. Adding lightness is priority number 1, and ailerons aren’t really necessary when roll control can be carried out through X-.taik mixing. I’d instead move the wing up.
@@howlingwolven The X tail doesn't have enough of a control moment (force x distance) to be effective at low speed, maybe at Mach 1, but not at launch speeds. A micro servo is only about 2 grams in weight. Moving the wings up would certainly help.
People like this absolutely amaze me. There are so many talented humans out there.
Do you happen to live in New Jersey?
you beat me to it
😂
no - otherwise it would fly.
@@haraldschurr1035really? He’s hand launching a rocket, what do you expect?
Lol
As someone who also jumped into the RC hobby with 0 experience and decided to build an extremely complex model, this video is amazing. You just dialed everything to 11.
Not really. It's more akin to somebody trying to summit Mount Everest as their first climb with 100 kg of camping gear and no oxygen. Basically can't even get to base camp with all that crap.
@toolbaggers That is a terrible analogy and completely misses the point of engineering projects like this. The goal is to learn just as much as it is to succeed. It also significantly underestimates the complexities involved in designing systems like this. It's not a matter of "grab the right stuff and throw it together". Your comment makes it seem like he set himself up to fail, and that the plane not flying somehow means the project was a failure. I'm going on about this because reactions like yours are extremely frustrating to read, and they completely undermine the spirit of hobby engineering.
Failure is always an option and success is on a spectrum. you learn more when you fail than when you get it right the first time.
Oh good! I was worried we would never get to loitering munitions but here we are
WTF are you talking about? He is building stuff that is already in service with the US military, he is literally copying others ideas so poorly that he is failing hard when the info to do this is already out there.
@@thomgizziz you are so nice and kind😊😊
@@thomgizziz "the info is already out there" put up or shut up, ill see you in the warthunder forums
munition? this is an... rc plane made for... filming
@@thomgizziz Jesus Christ my man.
Watching this made me realize that I have to learn to get good at CAD, holy smokes the visuals and design part is so cool!!
So for your first ever RC plane you naturally designed a DIY cruise missile. 😂 This is fully insane and I'm 100% here for it. Nice work.
This is so sick! One of the coolest DIY projects I've seen
Correct me if I'm wrong, but Hatchet is meant to be initially launched via rocket with the EDF just keeping it in the air. As such, redesigning it to be hand-launched seems like a step in the wrong direction. I think a catapult is a better idea, as it can provide the higher launch speeds that are needed without having to deal with the complexities of rocket launches.
Or a magnetic linear rail launch system like Tom Stanton and others have built before. Smooth, consistent acceleration. Though that doesn't help the whole cruise missile vibe!
Given that he has never flown a radio control plane before this would be a step in the right direction. Slower flying means more forgiving and easier to launch/test. Once he can make the hand launch version work, then he can work on increasing the wing loading and going faster/autonomous
I agree, engineering a propulsive launch with discarding sabot-style engine mount might be a simpler solution than fundamental redesigns to allow for low speed launches, nearly an entirely separate vehicle mission set...
Amazing work!
He could have also had someone else tow it with a rc (and a cradle with wheels to get it off the ground) like a glider and then ran the tests once it was already in the air.
Yeah, stuff like this is often RATO or JATO.
I love these kinds of videos, Thankyou for the detailed explanation!
Definitely reduce takeoff weight at least for early test flights. A rail launcher would be a game changer for getting you off the ground consistently with enough velocity to get enough lift out of the small wings. In addition, a rail launch would let you spin up your edf right before you launch. That way you are taking full advantage of your vectored thrust right as you leave the rail, when your control surfaces are going to really struggle giving you enough control authority.
Giant water balloon slingshot and pvc or wood rails
Thinking vertical launch with a potato cannon style launcher
Rail launcher, and put a large net downrange to catch those early failures. Later you can use the net for soft landings.
ERAU Grad, changing the air frame before getting it airborne is going to kill his understanding of how it flies in its ideal flight configuration. He should be focused on getting it airborne first then worry about changing it IMO.
Slingshot launch could help him dial in his v speeds without needing to redesign his aircraft.
Aerospace engineer here, seconding the rail launcher
This CAD work and prototyping is just awesome!
That ducted fan exhaust has an expanding nozzle. But your air isn't supersonic -- it's not even compressed. So the exhaust will slow down and increase pressure through this nozzle, which means the nozzle will pull backward on the vehicle.
You might want to switch to a converging (subsonic) nozzle.
Also, for those jet vanes to work, you'd need to have the nozzle terminate right about where the vanes are.
Also, isn't the center of lift on those vanes going to be through the 1/4 chord line? It looks to me that you may have the center of lift forward of the center of rotation. That's going to make the vane fight the servo whenever you try to reverse the control, which will increase hysteresis.
It doesn't look like you have enough lift. Did you calculate your stall speed? That thing looks like it's maybe 4 kg? With 910 cm^2 of wing area, you'll need 430 Pa to hold it up, so you'll need about that in dynamic pressure (assuming your wing shape can do at least CL=1.0). At sea level that's 26 m/s, about 59 mph. An NFL quarterback would be hard pressed to throw that hard. Maybe you could use a big rubber band to launch it.
Reducing weight 40% should reduce stall speed 20%. Dynamic pressure is 0.5*(air density)*(velocity)^2.
Welcome back switchblade 300
Shhhhhhh
I was thinking rail launcher when your buddy was chucking it. I really think you need tail wings. Those 4 X-patten, or even 2 larger Y-pattern stabilizers, are not enough. I think you need the 2 larger Y-pattern rudders and 2 normal rear wings, then you'll home free. Stall and launch speeds will be much better. Some kind of carbon landing sliders might also be good. At least it when you are finally landing it, it will not risk tearing up the bottom. That's my 2 cents.
13:15 the way your friend is throwing it here is forcing the plane to pitch up. If he can hold it at COM and guide it into the air under the planes own power, you’ll be able to keep control. Alternatively maybe a rail like the V1 can help you eliminate variables here. Looking forward to seeing more!
It seems like the drone is also way underpowered, as by the 2nd launch he didn't pitch it up much but the plane just fell like a rock
Rail indeed, but that needs thrust, even with too much weight it should have enough thrust to at least fly a meter or two.
RAIL LAUNCH SYSTEM 100%. take human error out, add much needed speed!!! make it repeatable.
@@eriknulty6392 Or even just a bungee/hi-start system like a lot of the EDF guys use.
No, no he can't. There isn't enough power and way too much weight. There is more than enough info out there that this dude should have figured this out before he failed like this.
I agree with your assessment that you have a yaw stability problem, first. Second, after you fix that, I agree with the other comments suggesting a catapult launch. Given the weight and designed launch mode, the hand launch simply isn't giving you enough velocity "off the rail". You may need a much larger wing to start with if you want to try that, but that carries more weight, more drag, and will again require you to add more yaw stability. Perhaps some longitudinal vanes to simulate more yaw control can help get you in the right direction.
I'd also ask - Have you done any CFD to see if the wings are producing any turbulence that may be masking those small control surfaces? Especially at the high AoA you're probably expecting, that airflow may be nasty. If the air is clean enough, have you run the numbers to see if they're imparting enough lift/torque for all three control axes (concurrently, when the controls are blended) at whatever airspeed you can achieve with your friend's arm?
1. Take off weight is too large, well, at least for the wing area you have chosen which is pretty much fixed if they are going to fold out of the fuselage eventually.
2. CG and wing placement seem to be mismatched, dangle it on a string from the mean chord, quarter chord point as a sanity check.
3. Control surfaces are too small for realistically any control during takeoff, and the fact you do not have ailerons would mean that they would need increasing in size compared to a normal set. For roll control matching ref area isn't sufficient as the moments are what counts, that close to the fuselage the moment will be tiny.
4. I'm unsure about the thrust vectoring, there is so much vorticity coming from that ducted fan that redirecting that flow is probably doing nothing apart from obstructing it, which leads me to the final point..
5. I don't think there is any thrust being made tbh. Compare just holding the plane at full throttle to what the fan is expected to produce.
Really cool project, I hope you can make it fly!
Pretty good points, I was also going to point out the thrust vectoring and thrust issues, I feel that the thrust vectoring needs to be eliminated, and the inlet needs a big redesign to let a lot more are in and directing it accordingly, I would provably go with an all around inlet or 4 inlets similar to that of a cruise missile, but nonetheless it needs a lot of air going in just because its fan propulsion, there is no pressure differential created by combustion and the air needs to enter as easily as it can, that design could hinder the air flow.
My thoughts exactly aswell, i'd argue that he could make it a biplan to double the wing area but even that may not be enough, and comes with additional drawbacks.
Yes point 5 seemed almost obvious, but I could be mistaken. With enough trust I would expect it to at least fly a few meters even with all the other points being an issue as well. I would've expected a thrust test inside. :)
RAIL LAUNCH SYSTEM 100%. take human error out, add much needed speed!!! make it repeatable.
Thrust vectoring is done with EDFs, stop it with the nonsense.
The slingshot rail launcher is a good idea, I'd hook at the front, as without momentum at the front, the "pusher" is basically flipping the rear around, hopefully yanking it on a rail from the front will have it up to speed so the pusher isn't "end-arounding" it. Good luck!
You should try a bungee launch. It is much faster and more predictable than a hand launch, especially with a new plane. Also before you risk your complex delicate powered drone, I suggest you create a simple unpowered model from a cardboard tube that is appropriately weighted and winged to perform the same as the real thing and try launching that as a glider. If it wont glide, at least a little then adjust things until it does.
this for sure. most of these lower thrust drones unfortunately jus cant take off without that inital push
Some suggestions.
More foam, less plastic. Foam wings.
Ideally make the whole fuselage out of foam halves with pockets for electronics and lightening.
Two fins, upward, V-tail, deploy them during flight so they don't interfere with booster.
Catapult launch.
Fins only need a small control surface, large stationary fins stabilize.
I think the little fins in your prop wash are more harmful then helpful. Planes usually use vectoring cones.
Put it on a vertical test stand and measure thrust. I don't think you have NEARLY enough. It should be able to take off from your unlucky friend's hand.
Related, maybe move to a 4" diameter? Bigger fan and fatter wings being the primary benefits.
Glad it's not just me, that looked underpowered before he even fired it up. Love the design, but it seems a little ambitious for that tiny ducted fan.
I think the intake under the rear is also causing it to pitch up by creating a vacuum under the rear.
Also think it 10 year old could come up with a better designed plane. So there’s that.
This. Thrust is lacking massively. Make a runway with a 'cart' to allow the craft to accelerate along and then take off when V1 is reached.
Just found this channel and I LOVE it! My 2c... Original design is like a cruise missile, which is typically launched at high speed - over 500 mph. Since you probably want to launch at closer to 7% of that for a hand launch, you need to make this like a small slow airplane. Control surfaces must be much much larger. Like 10 times the size for stability and authority at low speed, maybe bigger. And just do two on the top. No need for 2 little ones underneath. Wings also probably need to be larger - need to get that wing loading (lift/sq m) down. Weight is one way, but also more wing area. Also, no swept leading edge. Make it straight. How did you choose your airfoil cross section? You need more thrust. I bet if you put a scoop on the bottom a la F-16 (Or better yet, on the top like a Cirrus Vision Jet which also has a V tail) and got some ram air action going, rather than just suction, your CFM through the fan would go way way up. Finally, consider CG vs center of lift. You want your CG forward of CL but by how much? Moving CG back closer to CL can reduce required lift, but if you go too far you become too unstable. Go too far forward and you nose dive!
I am by no means an aerospace engineer, just a hobbyist drone/rc plane pilot. Here are my 2 cents: these first launch attempts look very similar to that I've experienced with my first rc plane (zohd nano talon). The problem with such planes is that they have a relatively high wing loading and are pretty hard to hand launch. I crashed my plane around 20 times before I figured out that you need to give it *much* more kick on the launch. Because of that I decided to bungee launch it. With bungee launcher it took off easily on the first try. My bungee setup consisted of 10 feet of rope attached to 10 feet of elastic band, the part with elastic band is attached to the hook on the ground. The other side with the rope has a loop which is attached to a hook mounted to the airplane. The hook should be mounted on the bottom of fuselage a bit forward of aircraft CG. Thanks for the great video. Best wishes from Ukraine.
Slava Ukraini - Героям слава!
@@8thday204shut up
How heavy is that thing? It looks like it weighs about 2x too much to hand launch. EDFs have basically no static thrust so the rail launch idea is definitely a good one but its a lot of time and effort when you need to focus on getting the characteristics of the airframe down first.
I'd build a super light one just to test the advanced control system you are using. Maybe a foam board tube with a light 3d printed nose cone combined with moving the wings backward so you can use your existing edf location and power unit. Im biased as foam board is my bread and butter go to material for model planes.
Also are you printing the plane out of any foaming light weight materials? I think they have just about everything in a LW version for RC planes nowadays.
If you need that payload weight to stay the same you can only take so much weight out of the structure while keeping it in that soze and form factor. If it were me, I would shoot for something about 30% to 50% larger while trying to keep the weight of the structure relatively the same. I would also do a pusher prop on a thrust vectoring base along with ailerons for controls. If you want to keep the wings light and simple canards can handle the roll and add a lot more pitch control.
Hope this helps! If you want to have a more in depth conversation let me know. I'll hop on the RC testflight discord.
A couple thoughts I had (although I don't do a lot of hobby drone stuff, I do work in aerospace)
1. 3d printed parts are probably not great for takeoff weight. It makes sense to use them for the aero surfaces where you need complex shapes, but you could probably cut down on their use in other places. The ball turret in particular strikes me as something that adds a lot of weight for something that still can't get a stable launch. Until you can get the prototype to reliably launch, maybe replace that and use a mass simulator to figure out what your mass budget for that payload is.
2. The inlet for the ducted fan looks like it's going to induce a pitch up moment that will vary with thrust, if possible, try replacing that with symmetric inlets so that you have more balanced aero forces. Also, having the inlet along the body like that makes me worry about losing thrust in high AoA situations, but at low speed, that's probably not as much of an issue.
3. I like the design of the control surfaces connected to thrust vector control vanes, but I worry about your proposed Y-tail idea. Non-symmetrical external control surfaces coupled to symmetrical internal control surfaces are going to require some complex control laws.
I can't speak for what filament he used but there are multiple 3d printing filaments out there designed for model aircraft - I'm assuming he used one of those filaments (?) I could be completely wrong, though.
@@amhedgehog in the video he clearly said that he was using normal petg for most of it with some higher strength stuff around the cameras.
The second I saw the first launch attempt, I thought in order: "too heavy" and "hmm maybe a bungee launcher would work. Seems you're on top of things and don't need my input. I'm excited to see what you come up with. My credentials are that I once duct taped a rock to a plane to balance the cg, and it flew great.
I might consider a weighted test article to hash out launch and glide ratio. Same weight layout and construction just without all the electronics. Inherently unstable works for fighter jets but your drone should be able to track mostly straight and glide even a little bit without input. This will also allow you to adjust CG location to determine balanced flight profile.
You’re on the right track with your iteration ideas. Keep going
Some thoughts: 1. Are Center of lift/Center of gravity at the right spot? 2. Is the air inlet sufficient enough to generate enough thrust? Look at pictures of older Tomahawk cruise missiles. They had some kind of duct sticking out below for good air intake. 3. Is the thrust even enough for the over all weight? From the video it seems quite a lot of weight in the front. 4. The steering rudders might be a bit small to give enough directional authority?
This guy almost certainly did this already before flying, that’s like RC planes 101. It’s just an inherently unstable design.
I feel like with a set of canards (moveable or not) and a better inlet (or any way to produce more thrust), most of the issues could be fixed but that's just my guess, I'm no expert after all
you summed up all my thoughts perfectly, especially the on with the air intake. Good Job man haha
@@olekXDDDD Thanks ;-)
Add short canards at the front and back to help stabilize lift maybe? And recheck cg for main wing?
If you get yourself some 3030 T slot aluminum you can easily put together a launcher for the drone using bunje cords. Im currently working on a long range survey drone, one main part is a launcher! You can also use compressed air to launch or even a magnetic rail but bunje or large rubber banding would do the trick nicely.
I think it needs to pass a glide test before you try powered flight. Make sure you've got the CG far enough forward to be stable and that the tail has enough downward pitch authority to keep the nose up.
Make the entire rear fin section magnetically detachable and use pogo pins to provide it power back there. Buy a compound bow and use that to get it up to launch speed; could probably make a stand utilize a garage door sensor to activate the full throttle condition to prevent any false launch events. I would also magnetically attach the wings as well if it remains fixed winged. Probably could add a simple parachute for free fall conditions as well.
Regarding your thoughts:
1. Yeah, your wing loading seems too high, especially considering you don't have highly cambered wings or flaps. You don't share numbers but for reference, a wing loading of 3.5 kg/m^3 will give a flight speed of 20mph at a coefficient of lift of 0.7. Printing your wings out of foaming filament can reduce their weight by like 40%, though you'd also want to incorporate a carbon spar.
2. Larger tail is necessary, but remember it doesn't all have to be all-moving control surfaces. If you want to experiment with stability margin, you could add a passive tail and reduce its size with progressive testing.
3. I agree rail launch with bungee is the safest way to get this thing up.
You might want to consider adding a scoop inlet for the edc, because it might be causing a low pressure zone and dragging the tail down. Might also protect the bottom fins and if printed in tpu could be flexible enough to absorb impact. Really freaking cool project man.
This is amazing dude. You casually made a Shahed-101. Looks like you learned why they use rocket assist take off. You also need a propeller about 3 times this size.
you can try adding foam on the belly to take the brunt of the landing, it also raises the planes height on the ground keeping you control surfaces safe. making it a y tail is good option, but would first run some CFD to analyze the plane's performance in various speeds.
cool video, cant wait to see it autonomous( pixhawk ftw)
In thrust we trust bruh.
I think those TVC vanes are trashing your thrust.
Obviously weight reduction is great but stick a flow meter behind the thing and see what’s up before you go tearing it apart.
12:30 Looks possibly tails heavy but for sure the thrust isn't enough for hand launch. Ideally you'd want the EDF to almost support the "plane"'s weight. Not sure how much roll control you have, you may want more dihedral especially for Mk. I.
I wonder, why a swept back wing design? Swept back wings are worse than straight wings as low speed lift goes, also they have less than ideal stall characteristics
Also those control surfaces might be still a bit too small but im not sure
Another thing, which airfoil are you using?
I'd suggest to calculate a rough Reynolds number you'll be operating at and use an airfoil with a lower efficiency but better stall characteristics at first, then maybe move to a more efficient airfoil
yeah, swept back wings should just be better at high speed in terms of drag
Здравствуйте коллега -)
The swept angle isn’t that bad, imo it’s a tapered wing. I agree the surfaces are too small
@@wire3989 i think a straight wing could still give some benefits to the build, or maybe I'm just a straight wing lover😅
The two things I'd suggest. Reducing weight is only a band aid. Figure out your V2 climb speed and design a catapult system that can rapidly accelerate the vehicle to that at a desirable angle and in a more stable way. The second thing is I'd suggest a more traditional rear stabilizer setup. There's a reason pretty much all aircraft have the vertical and horizontal stab planes rather than a rocket style configuration.
Good luck and love what you're doing.
I would recommend building a model as similar as possible out of dollar tree foamboard. It is important that you get the CG right, normally about 1/4 chord or slightly forward works great. Testing a foamboard model would allow you to have the lightweight model you need for takeoff and hand launching while also allowing you to gain an understanding where you are lacking in stability. It may not hurt to try and throw your model in XFLR5 without the fuselage and run a stability analysis with your current cg location and such to ensure your model is statically and dynamaically stable. This will also allow you to quickly change your model in software and give you a good place to start with real world testing. I do not recomend sweep for a model like this because it is not going fast enough for it to consider compressible factors. The things I recomended should give you a good starting point and understanding, giving you more time to come up with possibly more thrust for hand launching or bunge launching methods.
i think a rial launcher would probably be the best idea. that would get you in the air easier and with a more repeatable method. I think this is my first video of this series so i apologise if this has already been checked but have you done any thrust tests for that ducted fan? i would have expected something like that to at least pick up a bit of speed after a hand launch but it doesn't look like there is a whole lot of thrust coming from that. i do look forward to the next video and i will have to go back and watch the previous videos.
Honestly, with that endoframe- skip the intake duct and let the edf breathe, just open frame it without the intake. While the intake might be fine at speed, all of the airflow at takeoff is coming from the fan/ vacuum cleaner lol.
great point
A duct can help guide the airflow so it's not so turbulent going into the fan, but all sides should probably be opened up to get air from all sides.
After reducing take off weight, you could try diffrent types of launch, you could make some kind of catapult/slingshot/crossbow, the already mentioned rocket booster, or an aerial launch with a bigger craft, maybe not an aircraft but a drone that can lift it up enough to gain some speed
Please recalibrate the CG and CLs.
I really love the concept, so much room for even more potential. Regarding the wing surface area issue, have you ruled out all oldschool methods ? Particularly fabric skins? I imagined based on the earlier 2 part design (that had a high stall speed) but fabric or similarly malleable material stretching to form top & bottom skins. Allows a better airfoil profile, since its always landing like a convential plane and won't need to fold themselves back up until its on the ground, you could add some form of stringers for rigidity? Biggest restriction would be either end of speed envelope inducing turbulent flow over wing surfaces, flutter could run into immediate damage or failure if it's not super tight. 🤔 just an idea to brainstorm
I love it! Did you ever find the camera housing for the last rocket?
No :( it’s still Missing In Action
@@LafayetteSystems
RAIL LAUNCH SYSTEM 100%. take human error out, add much needed speed!!! make it repeatable.
I don't know where my reply are going
@ if you’re speaking about my comment, I think I had an unstable internet connection and so it posted my comment twice. I’ll delete one to eliminate the confusion.
@@jordandegraaff
Hello
pretty cool looking forward to the next video, maybe try a launch ramp for takeoffs
Maybe try attaching it to an existing flight worthy model and deploy once its at altitude, kinda like the space shuttle
Ooh I like this idea. In air deployment sounds cool. Although, given the use case which he outlined, it should still have the ability to hover at a constant altitude to track the rocket launch, so achieving stability at low speed is of paramount importance. But wait, how does he plan to hover again with TVC EDF firing at the rear and fixed wing?
Maybe you could put a solid rocket booster and get it into the air vertically and program the engine to start when the rocket motor exhausts self ejects itself. At least you’ll be able to test the gliding ratio before impailing the ground. I LOVE LOVE IT!! keep up the hard work very impressive.
I've been flying model airplanes for 23 years, but I've NEVER had such pain when looking at an "aircraft". 😅🎉
I am back after seeing the early videos. Dude is still at it and its cool as heck!
First! Love your videos, extremely underrated channel
It would be hard to make kinda but a slingshot could be a solid launch method, I’ve seen them used before and are quite good at getting them gently up to speed easily. Also an acrylic covering over the camera turret that matches up with the fuselage tube might help protect it better
I love your use of common techniques like 3D printing and common motors to build things like this, its really unique and most things like this are behind military walls
Seriously impressive. I applaud your approach of reducing risk where you can for initial testing. Too many people try to do too much too early, which usually results in multiple failures. Have yuo had any problems finding suitable test ranges? Launch attempts 1 & 2 - Hand launching probably gives you a takeoff speed too low to support flight, even for this wing set. Also, the takeoff angle of attack looks far too great, which probably resulted in stalling the wings. In an effort to eliminate those variables, you might consider using a track laucher with bungee cords for the initial takeoff impulse force.
Time to make a crossbow launch system.
Hi, very nice design. I think you should use the extra space you have obtained with the folding wing compartment to add new batteries.
What you want to achieve in the aerodynamic profile is to lock you tail at take off, add weight to the rear (batteries), enlarge you thin like a plane profile or even evolve from the X design to something able to produce the stability you need.
You could also work on the lack of thrust you'd need to take off as a rocket :p
10:25 Would adding a tight mesh cover over the inlet not be a good idea to prevent that?
it would reduce thrust by a very large amoung. either way a tiny motor like that is not gonna lift a brick so its never gonna fly
Firstly, I love this project it's cool as ...... On the constructive side I think your static thrust is to low for a hand launch, some options to solve that
1. the rail launch system has merit with the understanding that failure to achieve control will result in massive damage. 2. radically increase the power of the EDF and add an intake scoop to increase the efficiency of the EDF. 3. given your experience with rocketry build a fall away laugh booster that will give you both speed and altitude, the gentleman that taught me R/C flying always said, when trying something new "always fly three mistakes high" simple advise that has saved me many airframes (alas not all of them). I wish you success and I look forward to seeing your next project. Cheers from NZ
i am certain this man builds a missile and then sits and thinks for like 30 minutes about how to make it seem like its for amateur rocketry(i would do the same)
also: i would make it a stealthier cross section and put the inlet on the top.....ermmm i mean make it a lifting body and put the inlet on top to avoid FOD
Insane engineering right here, im barely getting to grips with blender at the moment would love to get into the electronics side of drone making , flew a few fpvs for a while and got pretty good but never built, also i print a lot 😃. Nice content man 👍
Some suggestions for your design.
1. Find and use a lightweight filament for this print.
2. Find and use some flight stability software.
3. Refine the inlet for the duct engine. I would add three duct inlets. One on the top and two on the side.
4. Increase the size of the wings to help with lift.
5. Move the wings to the aircraft's top to help with stability.
6. Rework the electronics so the center of gravity is just under the wings.
7. Remove all unnecessary equipment and only put what is needed to fly the drone.
8. Increase the size of your control surfaces.
I hope these suggestions help.
Loved the video! I'm an Aerospace Engineer and I recently jumped head-first into a similar-ish project without any sort of RC experience. My system is purely meant for relaxing FPV flights, but I think I have a lot of useful insights as I encountered pretty much everything you did in this video. First of all, for RC planes, getting off the ground is the single biggest hurdle. Your mass right now is excessively high. Generating lift is proportional to velocity squared. So at low to no velocity, you reducing weight isn't just beneficial, it's a requirement. Then, I believe the choice of an EDF is a major mismatch with what you're trying to accomplish. I know, it looks really cool (trust me, I also started with an EDF), but their thrust at low speeds is really poor and in general, thrust is limited by their small diameter. As such, I would instead opt to swap the engine out for a propeller in a pusher configuration. This will bring you much more thrust due to the larger diameter prop you can use, and it will also easily double or tripple your flight time since propellers are far more efficient than EDFs. Rocket launches take some time to set up, so if you want to monitor the entire process, having some margin on your flight time will be much appreciated. Unfortunately, the addition of a propeller will make your vision of a rocket-launched plane very difficult. It's a conflict of requirements, and you might have to make concessions. It might be worth employing a proper System Engineering approach and noting down your principle requirements and order them in terms of their importantce. Noting key and killer requirements will make the system a lot more functional in the end. IMPORTANT NOTE: There is a high likelihood that a rocket-launched plane like this is very much illegal to build and operate. (Hobby) Rockets are legal because they generally only go up. As soon as you aim to transfer to horizontal flight and actively steer them, you are building a cruise missile! Finally, for your control surfaces, I would generally ditch the thrust-vaning control. Its addition to controllability on top of the main fins is likely negligible.
Might you do test flights in NJ? At night?
i was working with the Mirach series (targets) and they're very similar to the design you're looking for, in my opinion try put on a charge for the starting propulsion for short takeoff (with a tilted angle) or as you said a rail catapult, but i think you can improve the design changing the air intake and putting it on the top (or bottom) of the model in order to increase the aerodynamic suction angle and don't lose stability due to the small mass of the plane. you need to have an incidence for takeoff for this kind of design. Tbh cool idea, you can create a simpler underwater version with the design you made, if you put a fixed wing and some radars below (i was looking into make a similar models myself but require too much time for design of the wing nozzle etc)
Swept wings are gonna kill your lift at low speeds, no reason to sweep wings unless you are pushing mach
BABE WAKE UP, LAFAYETTE JUST DROPPED A NEW VIDEO
She hasn't got enough thrust cap'n, that EDF jus' canne do et!
I have some experience in hand launching RC planes. When I just started the biggest mistake I made (and I can see you make it as well) was to through the plane upwards. This makes the plane immediately stall. Even though it is counter intuitive you should through the plane slightly downwards (to a imaginary point about 10 meters or 30 feet in front of you) this way the plane will have enough speed to fly or it will just land without (or the least amount of) damage.
If you wanna keep throwing it perhaps you could use an atlatl (spear thrower)
RAIL LAUNCH SYSTEM 100%. take human error out, add much needed speed!!! make it repeatable.
@@eriknulty6392 No, if the system is so screwed that you can't hand launch it then he probably isn't going to be able to hand fly it either. And spamming the same comment over and over again doesn't make it a better idea.
@@thomgizziz thats where you are wrong, that heavy bird with tiny control surfaces will fly great (AT HIGH SPEEDS). but going 4 mph you may as well just throw a brick. I do know a thing or 3 about building and flying scale planes, been doing it for 25+ years. but at that curb weight it wont fly until MIN. 20mph and thats probably even still pushing stall speed. she is a 50+ bird.
For hand launching try a wing tip launch. Hold it by the wing and spin and then release. Don't need as much strength that way. I am worried about the lack of control surfaces on the wings making it harder to control at low thrust. Another test is to empty out all the weight and see if you can get it to just glide.
I can't wait to see the changes you make to get Hatchet in the air.
Best of luck
I need this for searching for lost cattle on my farm. amazing design
Maybe print a Titan Falcon and get a FPV headset cheap plus IR video? No need to innovate when the solution is ready to print 😊 See YT videos, some militaries print them themselves to get cheap surveillance drones
@ but I want one that looks like a loitering munition for cool factor lol
@@TackshooterOG well, the Falcon gives you 300km range. But if you want cooler, how about the VTOL Titan Cobra? I actually just ordered parts for China for that one with FPV googles. Got them real cheap, like 60% off AliExpress since I lived in China and can buy it directly there. Still even with AliExpress parts, it's a damn cool morphing VTOL to Airplane
holy crap, this is your first drone. bananas. way to go Mr. Stark
I see two big problems. The thrust from your impeller is too low. Not only because it is a fairly inexpensive impeller but also because electrical impellers build up little static pressure in the impeller and the diameter behind the impeller is smaller than the impeller itself. I also think your center of gravity is too far back. For further experiments I would get away from the the thrustvector, use a better impeller and first build a traditional aircrafttail with larger control surfaces, in order to have a better chance of being able to handle any strange flight characteristics better.
Of course, a lighter aircraft always helps and could be successful when paird with a stronger impeller. If you want to achieve a good result, please only trust well-known manufacturers when it comes to thrust Statements.
Hope that helps.😊
You think his center of gravity is too far back when it was nose diving into the ground... really? You think you are helping? Your nonsense about "impellers" is even worse.
Your engineering skills are very impressive. nice design. Makes sense considering your job. I agree with oth sentiment of other comments, way faster launch, way more thrust (more battery voltage?) might get you in the air without too many mods. Bunje cords on a guide rail launcher would be cheap and easy to make.
Reducing the weight will definitely make launching easier. You need to prove out the airframe design, then incrementally add weight to make sure it can still launch and have stable flight and good stall characteristics (which helps with landing too) I’ve done bungee launches where I attach surgical tubing to a stake in the ground. Keep the airplane and launch as simple as possible, then build up from there. It does seem to be that the tail is a bit small as well. Vtails (or an x tail in your case) tend to have a harder time providing yaw stability.
Not experienced, but I flew an RC plane/glider thing that had collapsible blades. This could be used to launch it, they have good static pressure. The EDF fan doesn't seem to be doing anything at launch speeds. I think also the control surfaces don't do anything at low speeds. For initial testing, I would install some mesh around the intake port and some cage wire thing around the control surfaces.
that is some brillant work! well done! My guess is thrut to weight ratio is too low. Need more thrust scotty!
could you possibly discuss a bit more about the wing rotating mechanism? also how was the wing installed to the fuselage?
Very cool and ambitious project! Completely new desings are expected to end up in aerodynamics hell so hang in there! You should consider collaboration with another youtuber like Think Flight on this. He has experience designing and building winged drones so he might have some valuable input! In the meantime here are some ideas:
1) Push the center of mass forward, probably a lot. The aerodynamic center doesn't have enough leverage to keep the thing prograde.
2) Add ailerons on the wings for roll: Control authority far from the center of mass is a big yes.
3) I like the bigger top fins idea but a more traditional design might be more in order here for better control separation and whatnot. Rotate the back 45 degrees, add one big rudder fin on top and a bigger set of horizontal fins or even wings that can take over roll as well if big enough (they can also be set upside down for negative lift if you end up pushing the center of mass way forward and it ends up front-heavy).
4) Push or rotate the wings up to get a dihedral effect. Right now is looks like you get the opposite effect which actually gives the drone the tendency to go upside down.
Good luck! Subscribing for this!
All ideas does sound legit. I have flown aircraft that was unlaunchable from they landing gears using a launcher, but I would suggest finding a friend with a drone to launch it from high altitude, but I understand if thats not an option. Further I'd suggest doing a test model, basically the same thing with a prop, because the Edfs are often way worse for slow speed scenarios.aybe getting a simple prop Infront or aft would be a good test bed, that would also take away the need for a launcher. Good luck and thank you for the video!
I would either use a bungee launch. I dont think you even need a rail. Stake one end in the ground and attach a hook just forward of the center of lift. The other open is to build a drop plane. I know this can create another set of issues, but something like the FT Guinea Pig (cargo plane) from flitetest is very cheap and fast build. I've used it a few times when I need a quick drop plane for stuff in the past. Cool video and Good Luck
This is sick dude! Nice work
Great wildly ambitious project. 2question/suggestions:
1: What is the stall speed? - can your helper throw the vehicle (or anything) to that speed?
2: thrust? From the very limited view it looks like it is frankly insignificant relative to the mass of the vehicle. It is obviously unable to visually accelerate the vehicle in the first 1-2 seconds. Your idea of reducing total mass is good. But I’m thinking you need to maybe triple the thrust! Or how about rocket assistance for 5-10 seconds? Good luck
This is awesome. Looks like your tail thrust vectoring setup might be restricting the airflow of the ducted fan though?
hay there Lafayette Systems, wanted to suggest a little bit of an improvement. I would suggest that rather than having a inline inlet for the air, you put in a sort of scope or something which pushes the air into the engine from the front as i believe that the reason you stall is that you can't produce enough thrust to get off the ground with the air not getting feed in the engine. I would also suggest having some holes going around the engine just incase too much air gets traped infront of the fanblades. I hope this helps and wish you best of luck creating such an ausome program.
You can attach an assisted launch booster at the bottom of the drone, it should give it enough thrust in the launch stage to reach cruising speed. The current fan is also most likely too small to propel something of this size, the drone has the features of a cruise missile, you might need to increase wing span to get allow the drone to glide better, this can also reduce your excessive yaw rotation during launch.
cool design and this video was freakin awesome!
This thing is rad i love the idea I would consider building a launch catapult for these test launches you could rig one up pretty simple with some aluminum rail and surgical tubing and that could help make your test launches more consistent. The drone itself is pretty awesome though it reminds me of the US made Switchblade drones except i dont think those use ducted fans.
I build some RC airplanes I would improve these things : 1. make either a more conventional tail or V-tail (you can still make it fully movable if you want) and with much larger surface area (by eye I would say 3-4x bigger). 2. get a higher speed launching mechanism as you said. Some ideas you didnt mention are launching it from a stationary quadcopter in the air or from the back of a moving vehicule.
Wow, that thing is awesome!
I think you should definitely try the rail launcher. I would definitely remove the complicated servo portion from the wings and just make them spring loaded and retaned by a rubber band that can be cut with some nichrome wire heating up around it or something. That would remove alot of weight. The servos are cool but I dont see a need to retract the wings.
love it keep going def too heavy (hella low on power) also make a rail launcher
Good Luck Sir 🔥
One thing that might help with weight is replacing the printed body with a carbon fiber tube with a similar inner diameter (if available) might be able to cut a little weight off. Other than that I think that increasing the takeoff speed in addition to the weight saving measures you mentioned should help considerably.