I remember a flight I took about 30 years ago, before the days of frequent flyer miles. First class was virtually empty. A flight attendant asked me if I'd like to sit there. Of course, I said yes. She invited about ten or twelve of us to sit there. Now, I know why that happened. Thank you for explaining this. I had no idea.
I know why cabin crew need to ask the cockpit before let passengers upgrade their sit after boarding. Plus, I wanna ask, does the pilot really redo the calculation or they just like: I’m at the center, one or two people weight won’t do harm on the situation and just let them move?
@@edmondhung6097 Moving the left window seet to the right window seet over the wings can cause a 1+ DEGREE roll in a 747 .Cabin width 6.1 m so if you weight100 KG and center to cente of the 2 seets is 5.4 meters that is a 200 KG in ballince 100 KG taken from the left and added to the right = 200 KG weight diffrince acros the center line of the boddy and not the wings .
I got a Delta Comfort+ seat yesterday for no reason. I was very confused lol. The other seat in my row was empty too, it was great lol. This might explain things
17:30 As an ex-passenger agent at a small regional airport, we had a lot of ATR-72 and -42 aircraft, and this was a big problem. Whenever we had an ATR flight (more important with the 72 but we also did with the 42), we had to ask pax. in rows 1-10 to board first, as if there were more than 9 or 10 pax standing in the rear galley (where the entry door on almost all of this type of planes is), it was liable to tip. The "Tail Prop" is primarily there to gauge how close it is to tipping, and if it ever touched the ground it was a reportable incident. It staggered me as to how few people listened to the announcements (or outright flaunted them), as we were always very vigilant for those who didn't want to wait, and would (usually, and oh boy were there exceptions) politely tell them to take a small walk around the departure lounge. We also had to change seats last minute quite regularly, which was sometimes quite difficult with certain systems (think green text on a black screen, no mouse, and definitely no drag-and-drop!)
Quite some years ago I was a weight and balance engineer for Cessna. One of the airplanes I was responsible for, the Skymaster, would under certain load configurations have its center of gravity fall out of the flight envelope as fuel was burned. As long as the pilot did his calculation before flight it was safe but could be deadly if he or she skipped the calculations.
As a very young pilot, I once had to fly a box of parts in a Cessna 150. When I rotated on takeoff, the box slid back! That made the balance side of things real to me!
Scary man, reminds me of that Globemaster leaving (I think it was) Baghdad with a Abrhams tank that wasn't secured and must have rolled to the back, the thing just stalled and flopped onto the ground and exploded with full fuel. Did you return and land or see if you could slide forward with a steep dive?
When I was a fueler, we used to have to keep watch the balance of the fuel going into the wings. If we ended up with more than 1000lbs variance between the wings (one wing 1000 lbs heavier than the other), we had to call it in and request a mechanic to transfer fuel between the wings to balance them. We also occasionally got "weight restricted" flights, which was when the plane was full of passengers, and was flying a long distance. We had to put in the exact amount requested, and could not go over (usually we put in a couple hundred more pounds of fuel than requested just to be safe.) There was also a legend at the airport of one fueler who was fueling a British Airways 747, and wasn't paying attention. He ended up filling one wing, and not putting any fuel in the other wing, which became a 60,000 lb imbalance. The plane tipped over sideways.
I've seen this as a passenger. Someone managed to put enough fuel in only one wing to make the aircraft visibly tilt to the side. We then had to wait for about an hour until they transferred all the fuel over to the other side.
I thought the balance stuff was handled automatically by the fuel panel when you were fuelling. That or I am too spoiled with looking at the MD-11 which has an auto refuel mode that takes care of tank balancing for you, unless you need to set up ballast fuel.
I never thought about this subject before. I've often wondered why some planes, when they end up having less than a full load of passengers, often spread passengers out like checker pieces on a game board. Now I know why all of this calculation about weight placement also applies to the passenger luggage plus any "cargo" (such as mail) that is loaded onto the plane--and where and how. Thanks again for a very informational podcast (as usual).
Itis not only about pax boarding and disembarkation ,itis also about cargo or luggage loading and unloading which has a great effect on aircraft balancing on ground.all ground operations must be closely monitored. Thank for the video.
I work for a major airline. We have tail stands for our 737-9s. When I unload a 737, I can see the loader (belt loader) move up and down. It's actually the plane moving. Also when de-iceing in heavy snow they advise to start at the back to avoid tipping.
Some years ago there were public flights offered here in California on the Zeppelin NT "Eureka", where weight and balance were especially important when on the ground. So important that the loading procedure between groups of passengers included personnel stationed at the boarding stairs signaling to those of use about to go to them as to when we should each come forward. One passenger getting off would allow for one to come and get aboard. If the load was not completely full, there were weights added. This seemed to be necessary even with the rotatable side thrusters the airship had that could be employed to push the airship against the ground. Today the Goodyear company is using their version of the Zeppelin NT for advertising only, so I feel lucky to have had the opportunity to take a flight on such an unusual aircraft.
This was such an eye opening segment. I remember moving us back so our boat reaches ‘plane’ but I wasn’t aware of this in big jets. I went through reseating on a very small jet going Denver to Pueblo with myself and one 400+ pound person as the only passengers. They moved us several times. Also, thanks for explaining why we can’t have those nice, empty seats.
back in the 1980's, 90's, when the aircraft came on bay, the tech & cabin crew were off the aircraft so quick, you were blinded by the dust! On one occasion, on a B747, aircraft lost power, went dark, only 2 cabin crew on board (rest were a trail of dust). As an off duty engineer, I raced forward, started the APU and, called for ground crew so I could also get off myself, after all, I was off duty & on holidays. Cheers, Mr Mentour.
I was a ground agent for our regional carrier at the regional airport. The last inbound of the night landed with an angry captain. He made us take scales to the plane and weigh and record the weight of every bag as it came out of the EMB-120 before we released them to the customers. He also asked me how much I weighed. I told him that I was about 260 pounds. He sent me to the flight deck to pretend that I was a bunch of sand bags -- the nose gear was getting pretty long at the time. By the time the captain found out the bag weight -- EMB-120 with rear bag hold -- was a little more than 400 pounds too heavy, his blood pressure was sky high and he was on the phone to Houston before leaving the airport for the hotel. He was accusing people in Houston of trying to kill him and everyone on the airplane. Evidently he and his first officer had their hands full on the trip from IAH.
Delta and Alaska uses tail tip poles on their B739s during disembarking. This stops the tipping since they use a "jack point" on the rear near the APU. I also have seen the nose gear on a B738 FULLY extended on the ground while i was working for Sun Country as a ramp agent. We stopped offloading bags and quickly tried to get as many bags back on as possible in an effort to try to shift the weight enough to counter all the PAX in the rear. B738s and 739s, A320s and A321s are prone to tail tip since they are tail heavy...
that why I have an abort system that will save Jeb and kill Val. Also throw in a couple more rapiers then you can just make it go vertical, no COL needed.
Usually when I embarked on a plane, a regular seat was assigned to me. But I am 2 meters tall, with long legs. I usually don't fit in the tight regular economyseats. Fortunately for me, most flight attendants recognize it on the spot, and transfer me to a emergency-exit seat. That one of course is right on the center of gravity. But there was one flight I took where they put me in the front row, together with 2 other tall guys. I imagine now some other passengers had to be reseated as well, without the 3 of us realizing.
Honestly I enjoyed watching your analysis. I 've never heard this anywhere, never knew the weight of individuals and place of seat matters. Good job man.
I saw a Cessna 402 sit on it's tail once thanks to improper loading by UPS. About a week later the UPS facility, had a loop video playing in the loading area bout aircraft weight and balance.
I really enjoy these more physics-heavy(!) vids. But then I'm an engineer. Nice job presenting these aviation-physics topics to the public in an understandable way. Good work as well relating what an ordinary traveler might experience/witness (such as tail stands and delayed disembarkation) to aircraft/flight physics. I would be curious to know to what extent fuel consumption affects the aircraft CG over the course of a flight and what systems (human or automated) compensate for the changes and what the inputs to those systems are.
Many years ago at SFO I saw a DC8 tip. The ground crew was in a rush and didn't put the tail stand out. To make matters worse the cargo I was picking up had been misread off the airbill as 4lbs when it 4000lbs. All loaded in the aft bulk compartment. The company I worked for was a courier company and got a lot of questions. We kept track of the weight of the courier bags(most right at 70lbs). Not sure what else to say.
We sometimes have to stop unloading 737-900s from the front hold because of that scenario with passengers sitting in the back and people getting off the front. It happens a lot with the might-stopping 10pm KLM 737 which comes into Manchester and we usually have a tail tip risk warning because of it.
I seem to remember the Caravelle was quite a handful regarding balance while disembarking. I once saw an empty Caravelle with minimum fuel actually lift the nose wheel from the ground as one man walked up the rear airstair to remove the catering cabinets. I had to call out to him and get him down again.
A few years ago on a flight from Montreal, Canada to Montego Bay, Jamaica on an Air Transat Airbus A310-300 we made a stop in Puerto Plata, Dominican Republic to disembark about 180 passengers for their vacations out of the 250 passengers onboard. After they got off the plane the captain asked for about 10 passengers who were sitting in the front part of the cabin to move to the middle of the plane for the take off. After the take off they were permitted to regain their original seats as we flew to Montego Bay. This was in 2010 right after hurricane Tomas swept Haiti. Weight and balance demonstration live.
I caught a puddle-jumper out of Wichita once. We stopped somewhere and a few people got off. Then we stopped again, and some more people got off, which left me as the only passenger on the plane. The ramp worker stuck her head in the door and asked me to move to the back of the plane because they needed to balance the weight. I was a scrawny 17 year old, maybe 125 lb., but that really stuck with me!
I had one experience on a 737-200 flying out of the old Denver Stapleton to Little Rock. Backed away from the gate and figures computed. Lightly loaded pax and a flight attendant announced that they would have to move "one" person to correct a weight and balance problem. Very shortly after a VERY large adult was moved up to first class and off we went.
I've been doing loadsheets and weight and balance for major airlines for the past 20 years. Great to see it from a pilot's perspective. Love your content.
There was a discussion some years ago when average adult passenger weight was increased from about 70kg for estimating COG. What are the average weights now? P.S. "Momentum" is the product of mass and velocity. "Moment" is the product of force and the distance at which it's applied. Just a small quibble with our host's technical explanations.
thinking about that wouldnt it be a great idea to have scales at the gate or at checkin and then they can get it perfect. im assuming that would make something better but i cant think what exactly
With all the sandstorms in the Canary Islands, you should do a video on sandstorms and problems they might bring to aircraft. Maybe worth mentioning volcanic ash too? Thanks
Hi if you haven't covered it before I think I have a great idea for a video! From my flying lessons, my instructors told me the importance of not pushing the airframe past it's structural limits, as you've covered before. Now I've seen a number of large RC 1/2 scale jet turbine powered planes and a lot of them crash because of elevator or stabiliser flutter! I thought it could be very interesting for you to explain why this is so dangerous and dire for an aircraft to recover from.
Last summer I was flying from Oslo to Zurich in a B737. Something was wrong in the forward luggage compartment (possibly with one of the barriers mentioned at 10:26) and it was not possible to fix this quickly. The captain did not want to delay the departure further and decided to leave some luggage behind. Not only that not all suitcases could be stowed, some of the luggage that was already in the aircraft had to be unloaded again. During the push-back I saw my suitcase still on one of the carts on the apron ... When we arrived in Zurich, the captain instructed us to stay seated until the luggage (most of it stowed in the rear) was unloaded. I assume this was to avoid that the aircraft would tip. I was never denied to change a seat, but I remember a flight on a sparsely populated Fokker 50. I heard the captain saying to the flight attendants that each passenger has to stay exactly on the assigned seat, no seat changes allowed. Last September there were reports about a center of gravity issue with the A320neos of Lufthansa with the new "Space Flex" cabins . In simulations (never encountered during operations) it was discovered that the aircraft might have issues in certain go-around situations if the CoG is towards the rear of the aircraft. To avoid the issue, LH decided to keep the last row of seats empty on this aircraft type. British Airways did the same in their A320neos.
I remember two flights I took back in the nineties with ValuJet. When I arrived at the airport, I wasn't given a piece of paper with seatnumber, but a slip with my priority boarding. It was the 2nd or 3rd group. No seats were assigned and I could choose my own seat. So I sat right behind the cockpit. What I also noticed the plane was only filled for one-third. In retrospect, the company and crew were obviously not concerned with any balance issues.
I could’ve used this video when studying for my dispatcher exams. Granted, now that I’m working as such, I only ever have to manually do weight and balance when I’m planning a repositioning flight, ferry flight, or a functional check flight - or there’s so few passengers that it may through things off. Otherwise, our planning software does it for us. :)
cabin crew: we will be starting are dinner services shortly. pilot: hey google set a timer for 20 minutes titled set the horizontal stabilizer to plus 0.2
Another Dash-8 flyer, where one time on a full flight out of IAD, the co-pilot came back through the cabin with his computer, asking everyone's weight. When he got to the back of the plane, he had the ground crew remove a certain number of bags before we pushed back from the gate. We were hoping no one was lying about their weight :)
I remember when i the first time putting my digital reflex camera on the outside of the wing of an ASK-21 during aerobatics and how afraid i was because of weight and balance. 😰 It had no effect.🙈 Now i got four people with parachutes out of the center of gravity outside of the Cessna 182, a weight maybe near 350-400 kg and this time i have a lot of work to do to hold the plane stable! Sometimes things are changing... 😂
Very interesting video. Fascinating to understand better how important balance is for an aircraft. Never thought about that before. Thank you for posting. I learned a lot from this video. Keep up the good work.
I work as a Redcap and can't stress how important this is. I always tripplecheck the final figures before I do the the Weight and Balance with the pilots.
Thank you for this very informative Video. I love your channel for all these comprehensive explanations. As you mentioned the cases in wintertime, when airplanes sometimes have issues with imbalance during disembarking, I think of current COVID prevention measures with people staying seated until their row is called by the Purser. The crew needs to observe the perfect timing for each call so people keep on moving.
Some years ago we had issues with the A320/1 when rear steps were required on turnround for cleaners and refuelling. Guys had positioned the rear steps correctly on arrival but later when loading and boarding (via the airbridge) some ground teams didnt check the position of the rear steps until alerted by cabin crew who couldnt move the door. Due to the movement of the a/c and the design of the A320/1 door (it opens with the whole door over the top of the steps) the bottom of the a/c door was in some cases sitting wedged solidly onto the top step. The usual option was to move pax if they could and usually deflate the tyres on the steps pull them away and hope no damage had been done. Unfortunately on at least two occasions the aircraft doors were damaged causing (expensive) delays. A well balanced video. Thanks again.
I flew in a Bell 47 helicopter as a passenger. Before I climbed in the pilot moved a small weight from the very front of the helicopter to a mount on the tail boom to account for me. That was very interesting as the weight was only about the size of an apple.
I was in Maldives a few weeks ago. I was travelling by the hydroplane of Trans Maldivian Airlines. They had to weigh all our bags including hand luggage and it was all placed in the back of a cabin 😎 there was a stressful situation in our way back. Our biggest suitcase was missing, it didn't come with us, but we had to wait for the last plane to come. It was too heavy, I think.
I used to do the W & B for 3 different cargo 737-200's, we had software to calculate it and there was only 7-8 cans and the 2 belly holds so wasn't to hard just move them around to get the graph right and the pilot signs it off then make sure they are loaded in the correct order.
Good video! I remember many years ago in Sweden there was a fatal crash with a small turboprop plane. The reason was unbalance because of too much weight on the back of the plane. Shortly after take off the plane tipped over and crashed on the tail.
I used to fuel/ground handle a lot of 727s back in the day and It was always SOP to make sure the rear air stairs were down and locked as soon as the plane got to the gate and it was always the last thing put up before the airplane pushed. If a 727 had an aft fuel tank (not that many did), you always had to make sure both wings tanks and the center were full before even starting to fuel the aft tank. If the rear air stairs were inop there would have to be a tail stand attached to the strike / skid plate in back. I have seen those scissor links behind the nose gear on the 727 almost stretched to their limits before.
Just remembered another interesting scenario. Towards the end of TWA Airlines, passenger loads were way down. I can remember working MD 80s where if they didn't have at least 11 passengers on the flight we had to add ballast to the forward cargo bin and upgrade as many people to first class is we could to bring the aircraft into CG. We used to save the boxes of old Ambassador magazines to load in the forward cargo bin for ballast. There were also many times where even on short flights we would have to add 18,000 lb of fuel to the center tank just to get the aircraft within the CG.
By far the BEST channel in term of vulgarization civilian aviation's language , yesterday I look at the Tenerife episode by Mentour an incident that I thought I knew really really well but still Mentour made me learn many many things I didn't knew. And this is the same for all pubicly known catastrophes and crashes. Then you have thoses kind of explanatives videos that made everything so accessible to understand for a non aviation related person like me (I am an aviationthousiast with little knowledge but Mentour helps me a lot I really take pleasure in listening him he is a great teacher, a great youtuber and seems to be a genuinely great pilot). excuse my botchered english I did my best without translator so sorry for the nonsenses and bad written words if there are some. Thanks you for everything Mentour ! you're a great mentor. Is that what your pseudo means?
8:21 It's not all that complicated. Pat the little plane on the head, tell him he's a good boy for sitting down, give him a treat and he'll stand right back up.
In the mid 90s I worked at UPS. Per FAA regulation (at that time, probably still the same) the weight and balance people were included with the pilots in the random drug screening, that is how important weight and balance is.
I am surprised you didn't mention that 737's regularly use tail stands too. I see them all the time on the stretched versions like the -900ER of Alaska Airlines. They don't appear to be built in like the plane shown in the video, they look like ground based equipment.
Yes. The ground crew have a tail stand (pole) at the ramp ready for the 737-900ER. It’s spring loaded and fits into a small recess under the tail of the plane. It has two spirit levels parallel to the ground and at 90° to each other for the ramp worker to set it perfectly vertical.
Also the 727 which were often at the stand with the tail air-stairs in the lower position. In the past, I've deplaned off the rear stairs on a number of occasions.
I’ve had people ask me why the engines on T-Tail jets like the DC9 appear to intake higher than horizontal, therefore pitching the nose down.. maybe this could be a good podcast for you! 😉✈️
I remember a coworker fueling using crossfeed valves to transfer fuel from one wing to the other to balance the load. He fell asleep and woke up half hour later to see one wing almost touching the ground. He immediately had to send fuel back from that wing to the other. That was a close call. Everything smoothed out.
Great video Mentour I enjoyed watching it, i was on a Dash 8 once and could feel it tip slightly when i went down the back to take a photo, i went back to the front rather fast lol! Have a fantastic weekend my friend.
As you mentioned regards shipping containers and ships engines. Exactly the same on a ship only balanced out by pumping sea water into the Bilges. Usually lighter cargo (stuff) front and back in the cargo hold, with the heavy stuff in the middle. Not something you can do on an aircraft.
You should do one about how airplanes accommodate the disabled or handicapped (sorry if one term is not appropriate, I mean it with sincere positivity)? I'm referring to if someone was deaf and the safety lectures are done (is someone required to be sign language trained?) if they were asleep and an emergency occurred? If someone was in a wheelchair, needed crutches, etc what are the evacuation procedures, etc? I ask as I was recently in a car accident in October and haven't flown since, and worried to get on a plane due to my injuries. Thank you!
When the safety demonstration is done (at least the ones I remember) the flight attendant was demonstrating what to do with hand signals only, while the speaking part was solely audio coming from the seat speakers. I imagine this is for those who are deaf or hard-of-hearing.
I often fly on the ATR 72 with rear door entry/exit only. We used to be asked that the passengers in rows 1-10 remain seated until a least some of the rear passengers had disembarked. I always suspected it was for this reason.
Funny thing... on the flight i was on this monday, before takeoff the pilot said that too many people had reserved spaces in the front of the plain, and then asked for 10 people move to the back of the plain... i think the plain was about 1/3 full, i guess you just explained why...
The Boeing 727 Rear Air Stair Door was designed to be used as a "Pogo Stick" to support the tail while on the ground with 2 large hydraulic vertical rams. That allowed the aircraft to be loaded from the Back to the Front. That meant that no one was passing by people that were storing carry-on baggage and getting seated. Way more efficient way of loading. Great idea, AND the added benefit of a rear Entrance / Exit. Good design, but it used the extra length under the centre engine and inlet duct, which no longer exists on newer aircraft. FEDEX made good use of that provision for loading cargo.
The IL-62 had that tail wheel for that very reason probably. It was never used during taxi. Only when aircraft came to a stand still you would see the wheel on what looked like a telescopic strut drown down. I always wondered where it was stores since it wasn't folded it was straight down
Wasn’t that because the VC-10 design they stole was doctored by the Brits who were onto the fact that they were being spied on? They ended up with an out of balance plane so bodged it with an extra wheel! Well, that’s what my dad, a Rolls-Royce aero engine engineer told me. But he was a true commie-hating old cold warrior!
6:22 That happened to me in a very late night flight. The plane was mostly empty but plenty of people in the business class section where I was seated. The cabin crew at the request of the pilots moved me and a few business class passengers to economy class over the wings during take off to shift the balance of the plane.
So far I just realized Mentour is only one to properly balance his left right audio tracks - I have a special setup with Two soundbars hooked up to my computer using two different connections to them, and most videos sound like Karaoke Speakers kinda thing, and normally I have to adjust delay on one speaker normally my left speaker anywhere from 9MS to 70MS - but this video only needed 2MS - and that is within margin of error. :-D
This was a very good video and an explanation for those of us that want to pursue this as a career or just want to be a good/understanding/courteous passenger! Thank you so much!
Yeah, Air France learned that the hard way with the Concorde they crashed. They were over max takeoff weight and 4% tail heavy. There was a long list of other problems as well. Jersey Air had one where the load shifted on a cargo flight - not by much, but enough to mean that once they'd burned off the fuel during the flight, it became impossible to slow down because they ran out of elevator authority. They stalled on approach and crashed short of the runway.
I remember watching the 747 I was flying on getting loaded at Seattle and thinking they were putting all the cargo in the rear. Boarded the plane, set off down the taxi way and the pilot stopped the plane and went back to the terminal. He told us that the plane was out of balance and they'd have to reload it. Odd, and I wondered how it could happen....
I spent a day at Schiphol Airport (Netherlands) and standing on the visitorsplatform I saw a plane getting loaded. Aside from the regular passengerbags they shoved in about 10 of those preconfigured large metal containers. I remember thinking: how in the world is that plane going up? But it did. Of course it did.
Great video, also worth mentioning the horizontal balance especially on take off and landing. I was on a very quiet wide bodied aircraft where everyone wanted the vacation seats on the sides. They were quickly told they had to sit in the centre row for take off and landing to keep the plane stabilised. Great video though. Is there a reason you pronounce stabliser 'stab' but stable differently? It's a word you use alot and I'm sure everyone knows what you mean but thought I would mention it.
Petter says trust for thrust like Jamaicans & aircroft for the plane. When a fan asked a question he said aircroft also as he probably never heard it pronounced aircraft by anyone else. He was Indian.
The exact same thing with weight & balance happened once when me & my family were looking to buy a caravan. Caravans, just like the 737 have wheels in the middle and the front, nothing in the back and they have retractable struts in each corner by a crank-extended mechanism, the struts were retracted and we were going to look at things in the back, and all of a sudden, the caravan starts to sit itself on its back because no car was on the tow hitch, and we all ran up to the front in order to correct the weight imbalance.
Yes, when designing caravans care is taken in a rather similar way as with airplanes wrt center of pressure in relation to their center of gravity, and also for stability reasons. (IIRC c.of pressure should be slightly forward of c.of mass.)
When I started flight training I was badly overweight and had to take weight and balance very seriously. I've flown a Cessna 152 solo with full fuel tanks, but put anybody in the right seat and we're running the numbers to see how much fuel we can carry. Most 152 pilots are in the same situation.
The Ilyushin IL-62 (VC10ski) aircraft was so prone to tipping that it had a wheeled strut under the tail. The RAF VC10's, having a cargo door on the main floor, could load palletised freight, but the first pallet couldn't be moved beyond the wing roots until a second pallet had been loaded otherwise it would tip. I never saw one tip but the story of one tipping was lore throughout the RAF Movements trade.
I used to fly a small commuter jet in-and-out of Columbia Missouri, and chose not to be offended when asked to move around the aeroplane for weight and balance purposes. I am a rather sizeable, zaftig woman. 😆
Great video and explains a lot, however, how come long haul planes tend to have the first class and business class areas towards the front of the plane(less passengers), and the economy towards the back of the plane(more passengers)? Surly this would affect the COG massively?
Nice haircut, Petter! Two questions: are there mechanisms for the plane to measure its own weight, e.g., through some sensors? Are large planes able to control which tanks the engine fuel is coming from in order to help maintain desired weight and balance?
There's a story that a Concorde arrived at Heathrow from New York with very little fuel and was so unbalanced that they had difficulty getting the passengers off.
The way he explains the subject is really understandable and precise in all his videos. I enjoy these meticulously prepared videos and learn a lot. In this video, however, he mixed up two very important terms in mechanics: moment and momentum. Moment, in simple words, is the rotation effect of a force about an axis or a point. A more precise definition would be as follows: Moment of a force about a point or axis provides a measure of the tendency of the force to cause a body to rotate about the point or axis. Moment is the correct term that should have been used in this video to explain the aircraft stability. On the other hand, momentum (more precisely, linear momentum) is defined as the product of mass and velocity of a body. There is another term called angular momentum, which is the product of angular velocity and moment of inertia. Time rate of change of angular momentum of a body is equal to the net moment acting on the body (Newton's Second Law).
I remember a flight I took about 30 years ago, before the days of frequent flyer miles. First class was virtually empty. A flight attendant asked me if I'd like to sit there. Of course, I said yes. She invited about ten or twelve of us to sit there. Now, I know why that happened. Thank you for explaining this. I had no idea.
@J G That's what I thought until today. LOL
I know why cabin crew need to ask the cockpit before let passengers upgrade their sit after boarding. Plus, I wanna ask, does the pilot really redo the calculation or they just like: I’m at the center, one or two people weight won’t do harm on the situation and just let them move?
@@edmondhung6097 im not a pilot but im sure 100 or 200 kgs in 100ton or more plane wont make enough difference to bother doing the calculations
@@edmondhung6097 Moving the left window seet to the right window seet over the wings can cause a 1+ DEGREE roll in a 747 .Cabin width 6.1 m so if you weight100 KG and center to cente of the 2 seets is 5.4 meters that is a 200 KG in ballince 100 KG taken from the left and added to the right = 200 KG weight diffrince acros the center line of the boddy and not the wings .
I got a Delta Comfort+ seat yesterday for no reason. I was very confused lol. The other seat in my row was empty too, it was great lol. This might explain things
17:30 As an ex-passenger agent at a small regional airport, we had a lot of ATR-72 and -42 aircraft, and this was a big problem. Whenever we had an ATR flight (more important with the 72 but we also did with the 42), we had to ask pax. in rows 1-10 to board first, as if there were more than 9 or 10 pax standing in the rear galley (where the entry door on almost all of this type of planes is), it was liable to tip. The "Tail Prop" is primarily there to gauge how close it is to tipping, and if it ever touched the ground it was a reportable incident. It staggered me as to how few people listened to the announcements (or outright flaunted them), as we were always very vigilant for those who didn't want to wait, and would (usually, and oh boy were there exceptions) politely tell them to take a small walk around the departure lounge. We also had to change seats last minute quite regularly, which was sometimes quite difficult with certain systems (think green text on a black screen, no mouse, and definitely no drag-and-drop!)
Quite some years ago I was a weight and balance engineer for Cessna. One of the airplanes I was responsible for, the Skymaster, would under certain load configurations have its center of gravity fall out of the flight envelope as fuel was burned. As long as the pilot did his calculation before flight it was safe but could be deadly if he or she skipped the calculations.
As a very young pilot, I once had to fly a box of parts in a Cessna 150. When I rotated on takeoff, the box slid back! That made the balance side of things real to me!
Nice! LOL
Scary man, reminds me of that Globemaster leaving (I think it was) Baghdad with a Abrhams tank that wasn't secured and must have rolled to the back, the thing just stalled and flopped onto the ground and exploded with full fuel.
Did you return and land or see if you could slide forward with a steep dive?
@@thedave7760 Bagram airbase in Afghanistan. Very scary video!
@@thedave7760 it was a 747 hauling 3 AMRAPS/similar armored trucks.
@@jmacd8817
It was 5 vehicles. 2 lighter MRAPs and 3 heavier vehicles (can't remember the name).
When I was a fueler, we used to have to keep watch the balance of the fuel going into the wings. If we ended up with more than 1000lbs variance between the wings (one wing 1000 lbs heavier than the other), we had to call it in and request a mechanic to transfer fuel between the wings to balance them. We also occasionally got "weight restricted" flights, which was when the plane was full of passengers, and was flying a long distance. We had to put in the exact amount requested, and could not go over (usually we put in a couple hundred more pounds of fuel than requested just to be safe.) There was also a legend at the airport of one fueler who was fueling a British Airways 747, and wasn't paying attention. He ended up filling one wing, and not putting any fuel in the other wing, which became a 60,000 lb imbalance. The plane tipped over sideways.
That was a great man 🤣
I've seen this as a passenger. Someone managed to put enough fuel in only one wing to make the aircraft visibly tilt to the side. We then had to wait for about an hour until they transferred all the fuel over to the other side.
I thought the balance stuff was handled automatically by the fuel panel when you were fuelling.
That or I am too spoiled with looking at the MD-11 which has an auto refuel mode that takes care of tank balancing for you, unless you need to set up ballast fuel.
I never thought about this subject before. I've often wondered why some planes, when they end up having less than a full load of passengers, often spread passengers out like checker pieces on a game board. Now I know why all of this calculation about weight placement also applies to the passenger luggage plus any "cargo" (such as mail) that is loaded onto the plane--and where and how. Thanks again for a very informational podcast (as usual).
Itis not only about pax boarding and disembarkation ,itis also about cargo or luggage loading and unloading which has a great effect on aircraft balancing on ground.all ground operations must be closely monitored. Thank for the video.
I work for a major airline. We have tail stands for our 737-9s. When I unload a 737, I can see the loader (belt loader) move up and down. It's actually the plane moving. Also when de-iceing in heavy snow they advise to start at the back to avoid tipping.
Some years ago there were public flights offered here in California on the Zeppelin NT "Eureka", where weight and balance were especially important when on the ground. So important that the loading procedure between groups of passengers included personnel stationed at the boarding stairs signaling to those of use about to go to them as to when we should each come forward. One passenger getting off would allow for one to come and get aboard. If the load was not completely full, there were weights added. This seemed to be necessary even with the rotatable side thrusters the airship had that could be employed to push the airship against the ground.
Today the Goodyear company is using their version of the Zeppelin NT for advertising only, so I feel lucky to have had the opportunity to take a flight on such an unusual aircraft.
This was such an eye opening segment. I remember moving us back so our boat reaches ‘plane’ but I wasn’t aware of this in big jets. I went through reseating on a very small jet going Denver to Pueblo with myself and one 400+ pound person as the only passengers. They moved us several times. Also, thanks for explaining why we can’t have those nice, empty seats.
I really like the visual effects whenever you show the plane on screen.
back in the 1980's, 90's, when the aircraft came on bay, the tech & cabin crew were off the aircraft so quick, you were blinded by the dust! On one occasion, on a B747, aircraft lost power, went dark, only 2 cabin crew on board (rest were a trail of dust). As an off duty engineer, I raced forward, started the APU and, called for ground crew so I could also get off myself, after all, I was off duty & on holidays. Cheers, Mr Mentour.
The C-141 actually had cargo loading struts that you had to lower near the aft so that it wouldn't sit on it's tail during cargo loading/unloading.
I love how his dog keeps checking to see if he’s done.
well until hes done theres no chance of extra snacks or playing around
I was a ground agent for our regional carrier at the regional airport. The last inbound of the night landed with an angry captain. He made us take scales to the plane and weigh and record the weight of every bag as it came out of the EMB-120 before we released them to the customers. He also asked me how much I weighed. I told him that I was about 260 pounds. He sent me to the flight deck to pretend that I was a bunch of sand bags -- the nose gear was getting pretty long at the time. By the time the captain found out the bag weight -- EMB-120 with rear bag hold -- was a little more than 400 pounds too heavy, his blood pressure was sky high and he was on the phone to Houston before leaving the airport for the hotel. He was accusing people in Houston of trying to kill him and everyone on the airplane. Evidently he and his first officer had their hands full on the trip from IAH.
Delta and Alaska uses tail tip poles on their B739s during disembarking. This stops the tipping since they use a "jack point" on the rear near the APU. I also have seen the nose gear on a B738 FULLY extended on the ground while i was working for Sun Country as a ramp agent. We stopped offloading bags and quickly tried to get as many bags back on as possible in an effort to try to shift the weight enough to counter all the PAX in the rear. B738s and 739s, A320s and A321s are prone to tail tip since they are tail heavy...
I learned the fact that you want to offset the center of mass and the center of lift the hard way in Kerbal Space Program.
How many Kerbals have died in order to learn that lesson? I'm guessing a few thousand?
@@extrastuff9463 They blew up for a higher purpose.
J G besides spaceship, you also can build aircraft which fly aerodynamically
My thoughts just now xD
that why I have an abort system that will save Jeb and kill Val. Also throw in a couple more rapiers then you can just make it go vertical, no COL needed.
Usually when I embarked on a plane, a regular seat was assigned to me. But I am 2 meters tall, with long legs. I usually don't fit in the tight regular economyseats.
Fortunately for me, most flight attendants recognize it on the spot, and transfer me to a emergency-exit seat. That one of course is right on the center of gravity.
But there was one flight I took where they put me in the front row, together with 2 other tall guys. I imagine now some other passengers had to be reseated as well, without the 3 of us realizing.
Honestly I enjoyed watching your analysis. I 've never heard this anywhere, never knew the weight of individuals and place of seat matters. Good job man.
I saw a Cessna 402 sit on it's tail once thanks to improper loading by UPS. About a week later the UPS facility, had a loop video playing in the loading area bout aircraft weight and balance.
I really enjoy these more physics-heavy(!) vids. But then I'm an engineer. Nice job presenting these aviation-physics topics to the public in an understandable way. Good work as well relating what an ordinary traveler might experience/witness (such as tail stands and delayed disembarkation) to aircraft/flight physics. I would be curious to know to what extent fuel consumption affects the aircraft CG over the course of a flight and what systems (human or automated) compensate for the changes and what the inputs to those systems are.
C o G
I would think computers onboard handle this?
Many years ago at SFO I saw a DC8 tip. The ground crew was in a rush and didn't put the tail stand out. To make matters worse the cargo I was picking up had been misread off the airbill as 4lbs when it 4000lbs. All loaded in the aft bulk compartment.
The company I worked for was a courier company and got a lot of questions. We kept track of the weight of the courier bags(most right at 70lbs). Not sure what else to say.
We sometimes have to stop unloading 737-900s from the front hold because of that scenario with passengers sitting in the back and people getting off the front. It happens a lot with the might-stopping 10pm KLM 737 which comes into Manchester and we usually have a tail tip risk warning because of it.
I seem to remember the Caravelle was quite a handful regarding balance while disembarking. I once saw an empty Caravelle with minimum fuel actually lift the nose wheel from the ground as one man walked up the rear airstair to remove the catering cabinets. I had to call out to him and get him down again.
I had absolutely no clue but looking into it this makes perfect sense! I never noticed that because all my flights the plane had been full
A few years ago on a flight from Montreal, Canada to Montego Bay, Jamaica on an Air Transat Airbus A310-300 we made a stop in Puerto Plata, Dominican Republic to disembark about 180 passengers for their vacations out of the 250 passengers onboard.
After they got off the plane the captain asked for about 10 passengers who were sitting in the front part of the cabin to move to the middle of the plane for the take off. After the take off they were permitted to regain their original seats as we flew to Montego Bay.
This was in 2010 right after hurricane Tomas swept Haiti.
Weight and balance demonstration live.
Thanks MP for this vid and its surprising to learn how precise this weight balance procedure is.
I caught a puddle-jumper out of Wichita once. We stopped somewhere and a few people got off. Then we stopped again, and some more people got off, which left me as the only passenger on the plane. The ramp worker stuck her head in the door and asked me to move to the back of the plane because they needed to balance the weight. I was a scrawny 17 year old, maybe 125 lb., but that really stuck with me!
I had one experience on a 737-200 flying out of the old Denver Stapleton to Little Rock. Backed away from the gate and figures computed. Lightly loaded pax and a flight attendant announced that they would have to move "one" person to correct a weight and balance problem. Very shortly after a VERY large adult was moved up to first class and off we went.
I've been doing loadsheets and weight and balance for major airlines for the past 20 years. Great to see it from a pilot's perspective. Love your content.
There was a discussion some years ago when average adult passenger weight was increased from about 70kg for estimating COG. What are the average weights now?
P.S. "Momentum" is the product of mass and velocity. "Moment" is the product of force and the distance at which it's applied. Just a small quibble with our host's technical explanations.
thinking about that wouldnt it be a great idea to have scales at the gate or at checkin and then they can get it perfect. im assuming that would make something better but i cant think what exactly
Nominal weights we use now are 95kg for one passenger with carry on baggage 👍🏻
With all the sandstorms in the Canary Islands, you should do a video on sandstorms and problems they might bring to aircraft. Maybe worth mentioning volcanic ash too? Thanks
Hi if you haven't covered it before I think I have a great idea for a video! From my flying lessons, my instructors told me the importance of not pushing the airframe past it's structural limits, as you've covered before. Now I've seen a number of large RC 1/2 scale jet turbine powered planes and a lot of them crash because of elevator or stabiliser flutter! I thought it could be very interesting for you to explain why this is so dangerous and dire for an aircraft to recover from.
Last summer I was flying from Oslo to Zurich in a B737. Something was wrong in the forward luggage compartment (possibly with one of the barriers mentioned at 10:26) and it was not possible to fix this quickly. The captain did not want to delay the departure further and decided to leave some luggage behind. Not only that not all suitcases could be stowed, some of the luggage that was already in the aircraft had to be unloaded again. During the push-back I saw my suitcase still on one of the carts on the apron ...
When we arrived in Zurich, the captain instructed us to stay seated until the luggage (most of it stowed in the rear) was unloaded. I assume this was to avoid that the aircraft would tip.
I was never denied to change a seat, but I remember a flight on a sparsely populated Fokker 50. I heard the captain saying to the flight attendants that each passenger has to stay exactly on the assigned seat, no seat changes allowed.
Last September there were reports about a center of gravity issue with the A320neos of Lufthansa with the new "Space Flex" cabins . In simulations (never encountered during operations) it was discovered that the aircraft might have issues in certain go-around situations if the CoG is towards the rear of the aircraft. To avoid the issue, LH decided to keep the last row of seats empty on this aircraft type. British Airways did the same in their A320neos.
I remember two flights I took back in the nineties with ValuJet. When I arrived at the airport, I wasn't given a piece of paper with seatnumber, but a slip with my priority boarding. It was the 2nd or 3rd group. No seats were assigned and I could choose my own seat. So I sat right behind the cockpit.
What I also noticed the plane was only filled for one-third.
In retrospect, the company and crew were obviously not concerned with any balance issues.
Fantastic video! A great explanation on the horizontal stabilizers and the trim tabs. Thank you.
I could’ve used this video when studying for my dispatcher exams. Granted, now that I’m working as such, I only ever have to manually do weight and balance when I’m planning a repositioning flight, ferry flight, or a functional check flight - or there’s so few passengers that it may through things off. Otherwise, our planning software does it for us. :)
“Yeah, What Happened Then?” Nice. Patxi On Fire! I love it when he looks around. CJ
cabin crew: we will be starting are dinner services shortly.
pilot: hey google set a timer for 20 minutes titled set the horizontal stabilizer to plus 0.2
Pilot: "aircraft sit!"
Aircraft: *sits*
Pilot: "goooood boyyy"
Another Dash-8 flyer, where one time on a full flight out of IAD, the co-pilot came back through the cabin with his computer, asking everyone's weight. When he got to the back of the plane, he had the ground crew remove a certain number of bags before we pushed back from the gate. We were hoping no one was lying about their weight :)
There is some margin built in to the formula to deal with people lying about their weight.
I remember when i the first time putting my digital reflex camera on the outside of the wing of an ASK-21 during aerobatics and how afraid i was because of weight and balance. 😰
It had no effect.🙈
Now i got four people with parachutes out of the center of gravity outside of the Cessna 182, a weight maybe near 350-400 kg and this time i have a lot of work to do to hold the plane stable! Sometimes things are changing... 😂
Very interesting video. Fascinating to understand better how important balance is for an aircraft. Never thought about that before. Thank you for posting. I learned a lot from this video. Keep up the good work.
I work as a Redcap and can't stress how important this is. I always tripplecheck the final figures before I do the the Weight and Balance with the pilots.
Thank you for this very informative Video. I love your channel for all these comprehensive explanations.
As you mentioned the cases in wintertime, when airplanes sometimes have issues with imbalance during disembarking, I think of current COVID prevention measures with people staying seated until their row is called by the Purser. The crew needs to observe the perfect timing for each call so people keep on moving.
Some years ago we had issues with the A320/1 when rear steps were required on turnround for cleaners and refuelling. Guys had positioned the rear steps correctly on arrival but later when loading and boarding (via the airbridge) some ground teams didnt check the position of the rear steps until alerted by cabin crew who couldnt move the door. Due to the movement of the a/c and the design of the A320/1 door (it opens with the whole door over the top of the steps) the bottom of the a/c door was in some cases sitting wedged solidly onto the top step. The usual option was to move pax if they could and usually deflate the tyres on the steps pull them away and hope no damage had been done. Unfortunately on at least two occasions the aircraft doors were damaged causing (expensive) delays. A well balanced video. Thanks again.
Super interesting, I never realised that a plane was so weight sensitive. Great vid.
I flew in a Bell 47 helicopter as a passenger. Before I climbed in the pilot moved a small weight from the very front of the helicopter to a mount on the tail boom to account for me. That was very interesting as the weight was only about the size of an apple.
It's leverage. The tail is farther from the center of mass than you are, so less weight is needed.
I was in Maldives a few weeks ago. I was travelling by the hydroplane of Trans Maldivian Airlines. They had to weigh all our bags including hand luggage and it was all placed in the back of a cabin 😎 there was a stressful situation in our way back. Our biggest suitcase was missing, it didn't come with us, but we had to wait for the last plane to come. It was too heavy, I think.
I used to do the W & B for 3 different cargo 737-200's, we had software to calculate it and there was only 7-8 cans and the 2 belly holds so wasn't to hard just move them around to get the graph right and the pilot signs it off then make sure they are loaded in the correct order.
Good video!
I remember many years ago in Sweden there was a fatal crash with a small turboprop plane. The reason was unbalance because of too much weight on the back of the plane. Shortly after take off the plane tipped over and crashed on the tail.
I used to fuel/ground handle a lot of 727s back in the day and It was always SOP to make sure the rear air stairs were down and locked as soon as the plane got to the gate and it was always the last thing put up before the airplane pushed. If a 727 had an aft fuel tank (not that many did), you always had to make sure both wings tanks and the center were full before even starting to fuel the aft tank. If the rear air stairs were inop there would have to be a tail stand attached to the strike / skid plate in back. I have seen those scissor links behind the nose gear on the 727 almost stretched to their limits before.
Just remembered another interesting scenario. Towards the end of TWA Airlines, passenger loads were way down. I can remember working MD 80s where if they didn't have at least 11 passengers on the flight we had to add ballast to the forward cargo bin and upgrade as many people to first class is we could to bring the aircraft into CG. We used to save the boxes of old Ambassador magazines to load in the forward cargo bin for ballast. There were also many times where even on short flights we would have to add 18,000 lb of fuel to the center tank just to get the aircraft within the CG.
By far the BEST channel in term of vulgarization civilian aviation's language , yesterday I look at the Tenerife episode by Mentour an incident that I thought I knew really really well but still Mentour made me learn many many things I didn't knew. And this is the same for all pubicly known catastrophes and crashes.
Then you have thoses kind of explanatives videos that made everything so accessible to understand for a non aviation related person like me (I am an aviationthousiast with little knowledge but Mentour helps me a lot I really take pleasure in listening him he is a great teacher, a great youtuber and seems to be a genuinely great pilot).
excuse my botchered english I did my best without translator so sorry for the nonsenses and bad written words if there are some.
Thanks you for everything Mentour ! you're a great mentor. Is that what your pseudo means?
Thank you for your kind words! I’m happy you are enjoying the channel!
8:21 It's not all that complicated. Pat the little plane on the head, tell him he's a good boy for sitting down, give him a treat and he'll stand right back up.
V M Lol this is such an underrated comment😂
Loool
In the mid 90s I worked at UPS. Per FAA regulation (at that time, probably still the same) the weight and balance people were included with the pilots in the random drug screening, that is how important weight and balance is.
I am surprised you didn't mention that 737's regularly use tail stands too. I see them all the time on the stretched versions like the -900ER of Alaska Airlines. They don't appear to be built in like the plane shown in the video, they look like ground based equipment.
Yes. The ground crew have a tail stand (pole) at the ramp ready for the 737-900ER. It’s spring loaded and fits into a small recess under the tail of the plane. It has two spirit levels parallel to the ground and at 90° to each other for the ramp worker to set it perfectly vertical.
Also the 727 which were often at the stand with the tail air-stairs in the lower position. In the past, I've deplaned off the rear stairs on a number of occasions.
I’ve had people ask me why the engines on T-Tail jets like the DC9 appear to intake higher than horizontal, therefore pitching the nose down.. maybe this could be a good podcast for you! 😉✈️
I was waiting for the mean aerodynamic chord talk I got in my ground school for the B-727 FEX exam. Thanks for not booring us!
I learned a lot in 19 minutes!
I don't think you watched the whole video
I did
That's Brilliant! Check it out! Do it now!
Just ordered some tee shirts to support your work! Thank you for All Your Work. Hope you and your son are better!
The IL-62 also had a safety strut in the back :) It even had wheels.
I remember a coworker fueling using crossfeed valves to transfer fuel from one wing to the other to balance the load. He fell asleep and woke up half hour later to see one wing almost touching the ground. He immediately had to send fuel back from that wing to the other. That was a close call. Everything smoothed out.
Wow, disembarkation, never occurred to me. I was reminded of that horrid video of that military 747 that went down in Afghanistan due to load shift
Great video Mentour I enjoyed watching it, i was on a Dash 8 once and could feel it tip slightly when i went down the back to take a photo, i went back to the front rather fast lol! Have a fantastic weekend my friend.
As you mentioned regards shipping containers and ships engines. Exactly the same on a ship only balanced out by pumping sea water into the Bilges. Usually lighter cargo (stuff) front and back in the cargo hold, with the heavy stuff in the middle. Not something you can do on an aircraft.
You should do one about how airplanes accommodate the disabled or handicapped (sorry if one term is not appropriate, I mean it with sincere positivity)? I'm referring to if someone was deaf and the safety lectures are done (is someone required to be sign language trained?) if they were asleep and an emergency occurred? If someone was in a wheelchair, needed crutches, etc what are the evacuation procedures, etc? I ask as I was recently in a car accident in October and haven't flown since, and worried to get on a plane due to my injuries. Thank you!
Great idea for a video. Wishing you a speedy recovery.
When the safety demonstration is done (at least the ones I remember) the flight attendant was demonstrating what to do with hand signals only, while the speaking part was solely audio coming from the seat speakers. I imagine this is for those who are deaf or hard-of-hearing.
@@JustSomeCanuck Yes. And the safety brochure in the seat back pocket contains the same information as broadcast over the speakers in written form.
Good to know! Now I know what to tell fellow passengers who are annoyed for not disembarking fast.
I often fly on the ATR 72 with rear door entry/exit only. We used to be asked that the passengers in rows 1-10 remain seated until a least some of the rear passengers had disembarked. I always suspected it was for this reason.
I thought they put a support pillar on the tail on ATRs
@@sierraromeomike iiiiii9i
@@sierraromeomike iiii8ii8ii
@@sierraromeomike ii9
89i9i
Thank you. That was a very eloquent explanation of balance and moments.
Cool vid! Thanks!
Funny thing... on the flight i was on this monday, before takeoff the pilot said that too many people had reserved spaces in the front of the plain, and then asked for 10 people move to the back of the plain... i think the plain was about 1/3 full, i guess you just explained why...
Thank's for this, one of the most informative and interesting videos I've watched on UA-cam, explains so much.
while the disembarquing ... never tought that was a thing that is really interesting thks man ! great video well construct i love this channel !!!
The Boeing 727 Rear Air Stair Door was designed to be used as a "Pogo Stick" to support the tail while on the ground with 2 large hydraulic vertical rams. That allowed the aircraft to be loaded from the Back to the Front. That meant that no one was passing by people that were storing carry-on baggage and getting seated. Way more efficient way of loading. Great idea, AND the added benefit of a rear Entrance / Exit. Good design, but it used the extra length under the centre engine and inlet duct, which no longer exists on newer aircraft. FEDEX made good use of that provision for loading cargo.
The IL-62 had that tail wheel for that very reason probably. It was never used during taxi. Only when aircraft came to a stand still you would see the wheel on what looked like a telescopic strut drown down. I always wondered where it was stores since it wasn't folded it was straight down
Thanks for the great work commander, by far one of the best videos in my opinion.✈✈✈
Heyyyyyy!!!!!! Hello Commander! Hello Patxi! You Look Great! Feeling Much Better. I get very excited when you share something with us. Thnx, CJ
The IL-62 has a full blown drop wheel in the back. Kind of a fun thing to see on videos of the apron in the 1980s
The Russians know how to build airplanes like tanks, at least they did in the old days.
@@VMCAviationVideos yes, unfortunately, it is a thing in the past. The engineering ingenuity has left the country.
@@ci7alex1 Yes, sadly 😟
Wasn’t that because the VC-10 design they stole was doctored by the Brits who were onto the fact that they were being spied on? They ended up with an out of balance plane so bodged it with an extra wheel!
Well, that’s what my dad, a Rolls-Royce aero engine engineer told me. But he was a true commie-hating old cold warrior!
6:22 That happened to me in a very late night flight. The plane was mostly empty but plenty of people in the business class section where I was seated. The cabin crew at the request of the pilots moved me and a few business class passengers to economy class over the wings during take off to shift the balance of the plane.
No businessclass passenger protested when they had to sit in those tight seats?
On a dance disco boat the captain requestes us to move to the opposite port side as we were ready to sink. Then all was ok.
So far I just realized Mentour is only one to properly balance his left right audio tracks - I have a special setup with Two soundbars hooked up to my computer using two different connections to them, and most videos sound like Karaoke Speakers kinda thing, and normally I have to adjust delay on one speaker normally my left speaker anywhere from 9MS to 70MS - but this video only needed 2MS - and that is within margin of error. :-D
This was a very good video and an explanation for those of us that want to pursue this as a career or just want to be a good/understanding/courteous passenger! Thank you so much!
Thanks so much for the weights and balance video. Thumbs up!
Also, if the CG is too far aft, it makes stall recovery more difficult, if not impossible.
Yeah, Air France learned that the hard way with the Concorde they crashed. They were over max takeoff weight and 4% tail heavy. There was a long list of other problems as well.
Jersey Air had one where the load shifted on a cargo flight - not by much, but enough to mean that once they'd burned off the fuel during the flight, it became impossible to slow down because they ran out of elevator authority. They stalled on approach and crashed short of the runway.
I remember watching the 747 I was flying on getting loaded at Seattle and thinking they were putting all the cargo in the rear. Boarded the plane, set off down the taxi way and the pilot stopped the plane and went back to the terminal. He told us that the plane was out of balance and they'd have to reload it. Odd, and I wondered how it could happen....
I spent a day at Schiphol Airport (Netherlands) and standing on the visitorsplatform I saw a plane getting loaded. Aside from the regular passengerbags they shoved in about 10 of those preconfigured large metal containers. I remember thinking: how in the world is that plane going up?
But it did. Of course it did.
Great video, also worth mentioning the horizontal balance especially on take off and landing. I was on a very quiet wide bodied aircraft where everyone wanted the vacation seats on the sides. They were quickly told they had to sit in the centre row for take off and landing to keep the plane stabilised. Great video though. Is there a reason you pronounce stabliser 'stab' but stable differently? It's a word you use alot and I'm sure everyone knows what you mean but thought I would mention it.
Petter says trust for thrust like Jamaicans & aircroft for the plane. When a fan asked a question he said aircroft also as he probably never heard it pronounced aircraft by anyone else. He was Indian.
My mother flew in DC-3 s in the early 1950s and she said that passengers were instructed to sit in their seats from the back of the plane first.
The exact same thing with weight & balance happened once when me & my family were looking to buy a caravan. Caravans, just like the 737 have wheels in the middle and the front, nothing in the back and they have retractable struts in each corner by a crank-extended mechanism, the struts were retracted and we were going to look at things in the back, and all of a sudden, the caravan starts to sit itself on its back because no car was on the tow hitch, and we all ran up to the front in order to correct the weight imbalance.
What "retractable struts in each corner" are you talking about?
Yes, when designing caravans care is taken in a rather similar way as with airplanes wrt center of pressure in relation to their center of gravity, and also for stability reasons. (IIRC c.of pressure should be slightly forward of c.of mass.)
@@benhetland576 YOU: care is taken in a rather similar way as with airplanes *_wrt_* center of pressure
What is wrt?
When I started flight training I was badly overweight and had to take weight and balance very seriously.
I've flown a Cessna 152 solo with full fuel tanks, but put anybody in the right seat and we're running the numbers to see how much fuel we can carry. Most 152 pilots are in the same situation.
Simple yet excellent explanation sir! Very intuitive :)
The Ilyushin IL-62 (VC10ski) aircraft was so prone to tipping that it had a wheeled strut under the tail.
The RAF VC10's, having a cargo door on the main floor, could load palletised freight, but the first pallet couldn't be moved beyond the wing roots until a second pallet had been loaded otherwise it would tip. I never saw one tip but the story of one tipping was lore throughout the RAF Movements trade.
Wish you a absolutly fantastic day Mentour✌️
I used to fly a small commuter jet in-and-out of Columbia Missouri, and chose not to be offended when asked to move around the aeroplane for weight and balance purposes. I am a rather sizeable, zaftig woman. 😆
Great video and explains a lot, however, how come long haul planes tend to have the first class and business class areas towards the front of the plane(less passengers), and the economy towards the back of the plane(more passengers)? Surly this would affect the COG massively?
Very good explanation Peter. Thank you very much. Very informative as always
Nice haircut, Petter! Two questions: are there mechanisms for the plane to measure its own weight, e.g., through some sensors? Are large planes able to control which tanks the engine fuel is coming from in order to help maintain desired weight and balance?
Great info, in simple terms, that anyone can understand. Keep up the great job.
So I guess that is why they board first class first instead boarding the back first and move up. It would be faster but would make it tail heavy.
I am amazed at the amount of information and intelligence is present in Cap. Petter's mind... BRILLIANT!
¡Gracias!
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There's a story that a Concorde arrived at Heathrow from New York with very little fuel and was so unbalanced that they had difficulty getting the passengers off.
The way he explains the subject is really understandable and precise in all his videos. I enjoy these meticulously prepared videos and learn a lot. In this video, however, he mixed up two very important terms in mechanics: moment and momentum. Moment, in simple words, is the rotation effect of a force about an axis or a point. A more precise definition would be as follows: Moment of a force about a point or axis provides a measure of the tendency of the force to cause a body to rotate about the point or axis. Moment is the correct term that should have been used in this video to explain the aircraft stability. On the other hand, momentum (more precisely, linear momentum) is defined as the product of mass and velocity of a body. There is another term called angular momentum, which is the product of angular velocity and moment of inertia. Time rate of change of angular momentum of a body is equal to the net moment acting on the body (Newton's Second Law).
When speaking about the elevator downforce... Can you make a video on the Piaggio P-180 Avanti and why that design isn't used for larger aircraft?
12:52 - I need to know how to look that cool at 35,000 feet.
1) Download the Mentour Aviation app
Just step outside, you’ll be plenty cool at 35,000ft. Plus, you’ll be the center of everyone’s attention for just a moment.