ozziecat35
4 out of 5 great lakes prefer Michigan.
Perhaps the rotor heads can elaborate more on what exactly happened...regardless, still seems like some excellent airmanship.
Helicopter lands with stuck pedals
- Thread starter ozziecat35
- Start date
fast89pony
Well-Known Member
That was good great grand!
deadstick
Well-Known Member
Any number of issues can cause this (depending on the aircraft), but in general the pilot can no longer control the pitch of the t/r blade and the amount of anti-torque. In a fixed pitch scenario, that fixed amount of pedal/anti-torque will work for x amount of torque at y airspeed. Change one of those variables and the teeter totter gets upset.
As a helicopter slows, it takes more power (because of more pitch in the main rotor blades) to maintain flight AND thrust by the tail rotor to counter the torque. The fuselage and and vertical surface helps, but at some point, it's not enough. Then directional control is lost, as can be seen here. At that point, the pilot closes the throttle and enters an autorotation to a landing.
This was a good looking example.
As a helicopter slows, it takes more power (because of more pitch in the main rotor blades) to maintain flight AND thrust by the tail rotor to counter the torque. The fuselage and and vertical surface helps, but at some point, it's not enough. Then directional control is lost, as can be seen here. At that point, the pilot closes the throttle and enters an autorotation to a landing.
This was a good looking example.
This one looked weird, actually. He was clearly stuck left - increasing collective would bring him back right. It must have got stuck during a high power configuration. When that happens, you better have airspeed (which he did obviously) or it may be unrecoverable. I'd think in this case an option might be to reduce throttle to begin your decent, maintain rotor with collective - and maintain airspeed as reducing it would bring the nose left as well, and go for a run-on landing if you could bring the nose around. What I'm guessing is as he slowed he realized that increasing the collective as he slowed wasn't doing the trick and he auto'ed it in as deadstick said.
dustoff17
Still trying to reach the Top Shelf
@deadstick and @MikeFavinger explained it well.
As for the "armchairing", I might have aligned it, put it down sooner, and let them bill me for the skids. It started to get real ugly, real fast there at the end. He did a good job keeping it upright!
As for the "armchairing", I might have aligned it, put it down sooner, and let them bill me for the skids. It started to get real ugly, real fast there at the end. He did a good job keeping it upright!
deadstick
Well-Known Member
When he tucked the nose it looked like he might try to fly out of it liken LTE, but then just rolled off the throttle when that wasn't working. Who knows? The aircraft looked reusable (after a t/r repair). So "good landing." 
This is all from that video. I don't know what exactly was going on in there and, as @MikeFavinger alluded to, this can happen in any number of regimes.
I liked that big vertical stab in the 58 that off loads the t/r quite nicely, and this Enstrom (I've got 0.0 in type) just has those little stubbies.
This is all from that video. I don't know what exactly was going on in there and, as @MikeFavinger alluded to, this can happen in any number of regimes.
I liked that big vertical stab in the 58 that off loads the t/r quite nicely, and this Enstrom (I've got 0.0 in type) just has those little stubbies.
av8tr1
"Never tell me the odds!"
Ouch, that's Jack's third issue in a year. First the fatality, then 2 maintenance issues.....not looking well for the Denver crowd.
I would have done an auto, just remove the torque and do the full down. Was probably a below CFI rating level pilot who has no experience with full downs. Good example why we should be doing full downs sooner in training.
I would have done an auto, just remove the torque and do the full down. Was probably a below CFI rating level pilot who has no experience with full downs. Good example why we should be doing full downs sooner in training.
Murdoughnut
Well sized member
Pff - we tricycle geared, fixed wing pilots don't even touch our pedals the first 50 hours.
deadstick
Well-Known Member
On the other side of the spectrum, I hear some of those airliner type of pilots don't touch 'me either.
deadstick
Well-Known Member
av8tr1
"Never tell me the odds!"
That's as silly teaching full stalls and spins to private pilot students.
LOL, I see what you did there.......
Incidentally, when I first started to fly, they WERE teaching full stalls and spins to private students.
Man, I'm old.
deadstick
Well-Known Member
No kidding.
With autos, the last 10 ft are the hardest to not screw up. Losing directional control in the touchdown, hit one skid first, bleed off too much rotor RPM (no bueno in a Robbie), there are so many way to ball-up the ship and kill yourself in those last seconds.
You have to flare and pull pitch at some point. With no pedal control, you're not going to have a good day, end game. Better off with a shallow approach to a slide-on, I'd think. With a good landing direction, winds favoring the anti-torque side, shouldn't be too bad even though it could be dicey. May take an approach or two to get it right prior to touchdown.
That's the beauty of the helos with a manual throttle you can roll on, off or anywhere inbetween. Vice some modern FADEC birds which have just idle and fly, forcing you to have to finesse the speed reduction and the collective motion timing just right to have them all match at instant of touchdown, before loss of directional control.
av8tr1
"Never tell me the odds!"
No kidding.
With autos, the last 10 ft are the hardest to not screw up. Losing directional control in the touchdown, hit one skid first, bleed off too much rotor RPM (no bueno in a Robbie), there are so many way to ball-up the ship and kill yourself in those last seconds.
You know what, you're right. I stand corrected I would need the pedals in the touch down. Wouldn't a concern with the Enstrom is, like the Schweitzer, be ground resonance as well?
In the AStar B2 & 2B1, where there is no throttle modulation in this EP, just collective motion; on touchdown with stuck pedals, you still work the collective slightly to maintain directional control, but once the bulk of the weight sets in, you can slowly lower the collective to allow the weight of the helo to stop the bird. With a helo with no shock absorbers of any kind on the struts, I suppose its possible, but something would have to throw the rotor system out of balance also to begin ground reasonabce, and I haven't yet seen it even incipient in these slide on landings.
Nark
Macho Superpilot
We just finished up 4 hours EP's in the sim just the other week.
Fun isn't the right word, but being able to see and try your best not to crash during a stuck peddle was interesting.
Also thrown into other EP's, (like Left rotation) I've learned to pretty much find the softest spot to crash.
Kudos to this guy, for being able to use the airframe again.
Fun isn't the right word, but being able to see and try your best not to crash during a stuck peddle was interesting.
Also thrown into other EP's, (like Left rotation) I've learned to pretty much find the softest spot to crash.
Kudos to this guy, for being able to use the airframe again.
deadstick
Well-Known Member
I think we discussed throttle placement after the Airbus got balled up at UNM -- that just sucks. However I thought the FADEC could be overridden or turned off. I think the 407 has a twist grip and FADEC so it should able to accomplish this.
I think on a full down auto, with no power and the collective on the floor, that it wouldn't be an issue.
In the future, the direction of rotation will be interesting with training. Thinking of recency and repetition, the new students going through the UH72 will instinctively have everything going backwards in an auto when they go to the line aircraft.