Good morning everybody , thanks sir for this interesting presentation. I think before install the tail rotor servo actuator rod end bearing or the main rotor actuators rod end bearing we must putt all on the specific tools of the servo actuators . Best regards
Funny! Looks like an Air Methods paint scheme minus the star of life that's on the lateral cargo bay door. I wonder if it's an old Air Methods ship that's made it's way to Canada from the USA. We phased out all B2 and BA models that did not have a VEMD.
Just what I was looking for. Thanks for producing this video, Jonathan. I have questions about hydraulic servo actuator redundancy. Do you have a moment? On the AS350B3e models you have 2 separate / independent hydraulic systems to manipulate the control links of the main rotor stationary swashplate. I believe the servo actuators are twin cylinders for each link, and I'm assuming that each cylinder receives hydraulic pressure from separate hydraulic sources. If there is a failure in one of those two cylinders, causing it to restrict movement, while simultaneously having a hydraulic PSI greater than the properly functioning one, can it also inhibit the properly functioning cylinder by over-powering it? Are there separate pressure relief valves / check valves, one for each side? If so, is this considered a failsafe design? I'm new to hydraulics and have decided to do some research on my own. The Astar B3e seems like the ultimate single engine turbine helicopter, from a flight control redundancy perspective. (maybe the Agusta A119 Koala too) I wonder if there aren't some caveats or gotcha's even with the secondary hydraulic power. Do you think it is twice as safe as a Bell 407, in this regard? Thanks for any time you can spend answering my questions !
Hello! Love your question! You are correct on the AS350B3e the dual hyd system uses double cylinder servo actuators. It is a failsafe design and the loss of one system or blocking doesn't prevent the other one from taking over. It has a complex dual distribution valve on the servo. The single hydraulic system on the AS350 uses small accumulators on the servos, so if there is a hyd failure the pilot has stored energy to be able to bring the helicopter to a slower speed at which point the rotor forces are low enough where the pilot can handle the forces directly (basically like driving your car without power steering) so it's another type of "fail safe" where in case of failure you can still manage to land safely. I'm not familiar with the Koala system, I mostly work on the AS350 family. I have worked on the 407 but not that much and it's been a while. Most manufacturers implement a type of redundancy in their design. Hope it answered your question and please feel free to ask more! I can send you some more info privately if you like.
@@jonathanmarcoux9527 Thank you for the education and timely response. The infield servicing and component replacement process is very interesting and satisfying to observe. Much respect from this low time rotary wing pilot. I read a NTSB report that suggested that the tail rotor servo should be a 2-cylinder unit like the others on the ship. This would remove the pre-takeoff accumulator test step and negate the risks of the pilot forgetting to recharge(reactivate?) the system before pulling the collective to a hover. Given the crash review, it kind of makes good sense. Has that change been made in recent models? I'm subscribing, so keep those awesome videos coming!
@@jonathanmarcoux9527 I'm no lawyer and I don't work for a law firm either! Just curious... Last 4 questions I promise! Are all the hydraulics considered "open loop" or "closed loop"? Are the 2 cylinders considered "in series", " in parallel", or are they another description given the complex dual distribution valve? Can one expect some seepage from the actuators at the end of a day of operation? Are there periodic leak down tests to determine if the oil seals are linking beyond a pre-specified valve? Or, is this just upon visible inspection? My recent study of hydraulics stems from watching a disturbing video on UA-cam where an A-Star took-off from a beach, climbed to about 300ft AGL, then pitched nose up and banked steeply to the left...crashing into the sea. As a helicopter pilot and powersports parts manager, I'm shocked and have wondered how such a thing could happen. No need to speculate on the crash, I'm just curious about how these advanced helicopters work. I never had to worry about this on the Hughes 269, which I trained on. Thank you
@@llwellyn1 Thank you! I hope I can put up videos more often! On the B3e one system does the main and the tail and the other system does only the main. So basically the rear servo is still hooked up to only one system. It is still like that with new ones, I havent heard of wanting to change it. The tail servo has a "load compensator" with an accumulator built into it also for hyd loss.
Ture, the video doesnt show the laptop with the manuals in the truck. Could put in more context in future videos. Thanks for the feedback and thanks for your service!
Good morning everybody , thanks sir for this interesting presentation.
I think before install the tail rotor servo actuator rod end bearing or the main rotor actuators rod end bearing we must putt all on the specific tools of the servo actuators .
Best regards
Very nice. I am myself aircraft mechanic. AS350 is my favourite chopper. Keep up buddy.
Thanks! I mostly work with the AS350. Keep up the good work too!
@@jonathanmarcoux9527 So how is bell 407, I am planning one.
how is bell 407, I am planning to acquire.
@@naughtyUphillboy I havn't work much with the 407 but depending on what you intend to use it for it is nice smooth riding.
Been there done that as well as M/R servo's. Have had the T/R short shaft that couldn't be balanced at all. Had to replace it.
I've had a T/R that was hard to balance.
Funny! Looks like an Air Methods paint scheme minus the star of life that's on the lateral cargo bay door. I wonder if it's an old Air Methods ship that's made it's way to Canada from the USA. We phased out all B2 and BA models that did not have a VEMD.
Interesting! I am not aware of its previous history, what I do know is that it used to be an Allstar, The mod with the RR-250 turbine.
Just what I was looking for. Thanks for producing this video, Jonathan. I have questions about hydraulic servo actuator redundancy. Do you have a moment?
On the AS350B3e models you have 2 separate / independent hydraulic systems to manipulate the control links of the main rotor stationary swashplate. I believe the servo actuators are twin cylinders for each link, and I'm assuming that each cylinder receives hydraulic pressure from separate hydraulic sources. If there is a failure in one of those two cylinders, causing it to restrict movement, while simultaneously having a hydraulic PSI greater than the properly functioning one, can it also inhibit the properly functioning cylinder by over-powering it? Are there separate pressure relief valves / check valves, one for each side? If so, is this considered a failsafe design?
I'm new to hydraulics and have decided to do some research on my own. The Astar B3e seems like the ultimate single engine turbine helicopter, from a flight control redundancy perspective. (maybe the Agusta A119 Koala too) I wonder if there aren't some caveats or gotcha's even with the secondary hydraulic power. Do you think it is twice as safe as a Bell 407, in this regard?
Thanks for any time you can spend answering my questions !
Hello! Love your question! You are correct on the AS350B3e the dual hyd system uses double cylinder servo actuators. It is a failsafe design and the loss of one system or blocking doesn't prevent the other one from taking over. It has a complex dual distribution valve on the servo. The single hydraulic system on the AS350 uses small accumulators on the servos, so if there is a hyd failure the pilot has stored energy to be able to bring the helicopter to a slower speed at which point the rotor forces are low enough where the pilot can handle the forces directly (basically like driving your car without power steering) so it's another type of "fail safe" where in case of failure you can still manage to land safely. I'm not familiar with the Koala system, I mostly work on the AS350 family. I have worked on the 407 but not that much and it's been a while. Most manufacturers implement a type of redundancy in their design. Hope it answered your question and please feel free to ask more! I can send you some more info privately if you like.
@@jonathanmarcoux9527 Thank you for the education and timely response. The infield servicing and component replacement process is very interesting and satisfying to observe. Much respect from this low time rotary wing pilot.
I read a NTSB report that suggested that the tail rotor servo should be a 2-cylinder unit like the others on the ship. This would remove the pre-takeoff accumulator test step and negate the risks of the pilot forgetting to recharge(reactivate?) the system before pulling the collective to a hover. Given the crash review, it kind of makes good sense. Has that change been made in recent models?
I'm subscribing, so keep those awesome videos coming!
@@jonathanmarcoux9527 I'm no lawyer and I don't work for a law firm either! Just curious...
Last 4 questions I promise! Are all the hydraulics considered "open loop" or "closed loop"? Are the 2 cylinders considered "in series", " in parallel", or are they another description given the complex dual distribution valve? Can one expect some seepage from the actuators at the end of a day of operation? Are there periodic leak down tests to determine if the oil seals are linking beyond a pre-specified valve? Or, is this just upon visible inspection?
My recent study of hydraulics stems from watching a disturbing video on UA-cam where an A-Star took-off from a beach, climbed to about 300ft AGL, then pitched nose up and banked steeply to the left...crashing into the sea. As a helicopter pilot and powersports parts manager, I'm shocked and have wondered how such a thing could happen. No need to speculate on the crash, I'm just curious about how these advanced helicopters work. I never had to worry about this on the Hughes 269, which I trained on.
Thank you
@@llwellyn1 Thank you! I hope I can put up videos more often! On the B3e one system does the main and the tail and the other system does only the main. So basically the rear servo is still hooked up to only one system. It is still like that with new ones, I havent heard of wanting to change it. The tail servo has a "load compensator" with an accumulator built into it also for hyd loss.
@@jonathanmarcoux9527 Thank You Jonathan !
Nice work ...
Failed to check the torque on the Servo check valve.
You are right, its not shown in the edit.
Well done…
Interest.
82ND AIRBORNE
Where is the Manual?? Where is the FOD canister?? Effing civilians!!
Ture, the video doesnt show the laptop with the manuals in the truck. Could put in more context in future videos. Thanks for the feedback and thanks for your service!
@@jonathanmarcoux9527
82ND AIRBORNE
You are most welcome Jon!!