Autorotation

brien23

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Why practice Autorotation in helicopters we loose more in practice than we would ever loose in the real event. The old Bell and Hiller with wood blades had a lot of inertia, probably why their are so many still around. The R-22 and other helicopters with light inertia rotor systems might as well take what happens as we loose a lot in training how many and how much worse could it be without practice autorotation.
 
Why practice Autorotation in helicopters we loose more in practice than we would ever loose in the real event.

The objective is not to prevent helicopter losses. It is to prevent loss of life.

During training you have an experienced pilot (the CFI) and the trainee learning how. The fact that there are so many accidents is prima facie evidence that the training is necessary.

Would you really want to load your family on to a helicopter for say a sightseeing flight, knowing that, if the engine quit, the pilot would be doing his first full down autorotation ever?

-Skip
 
Would you really want to load your family on to a helicopter for say a sightseeing flight, knowing that, if the engine quit, the pilot would be doing his first full down autorotation ever?

The engine quit is a very small number of autorotations, simulated engine out cause more crash problems and people die in them. The question was are the loss of training autorotation worth the loss over the real small amount or real engine out autorotations. In R-22 loss of less then 75% rotor speed with engine out you may never get it back before you hit the ground, better time spent in never letting this happen, than full autorotations to the ground.
 
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....and people die in them.

The FAA has a mandate to protect the general public. "people", meaning the general public, don't die in a training practice autorotation, it is the flight crew that dies. Sad, yes. The FAA doesn't care as much about the flight crew. Want to change that? Write your congresscritters.

-Skip
 
The old Bell and Hiller with wood blades had a lot of inertia, probably why their are so many still around.

I learned to fly helicopters in the Army OH-23D (Hiller). It had low inertia blades, unlike the UH-1 or OH-58 for example. Autorotations in all of them were simply a matter of practice. In the Hiller, you waited until you were closer to the ground before pulling collective pitch. All of us students got used to it, no sweat. The good news about low inertia blades is that if you have a little bit of altitude and happen to have low rotor rpm, you can more quickly recover it by lowering nose or collective or both. Full touchdown autos were routine.

Haven't flown a Robinson, so I can't speak to that.
 
how many and how much worse could it be without practice autorotation.
Most companies to include the military do not regularly perform full touchdown autos anymore. Most terminate into a power recovery hover. Some companies still do full autos but they are few and far between. I don't know for sure, but I do not think full autos are required for the practical test on COM ticket anymore. V 173 might be able to confirm that. This AC gives some background on your question:
https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_61-140A.pdf

As to auto practice, considering I've flown with hundreds of pilots over the years, you can spot those who have practiced and those who lack practice. Especially when we were adjusting the autoration speeds after maintenance which may require several "practice" autos to get the speed right, but none of these would terminate to the ground.

And yes, heavy vs light blades make a difference. Each have the pros and cons which the pilot needs to be on top of. There was always one unfortunate guy who would transition from a Bell 206 (heavy) into an AS350 (light) and then lose an engine his 1st or 2nd week. Most of these MAYDAY calls usually had the low rotor blaring in the background which on older 350s was a Renault truck horn.
 
I learned to fly helicopters in the Army OH-23D (Hiller). It had low inertia blades, unlike the UH-1 or OH-58 for example. Autorotations in all of them were simply a matter of practice. In the Hiller, you waited until you were closer to the ground before pulling collective pitch. All of us students got used to it, no sweat. The good news about low inertia blades is that if you have a little bit of altitude and happen to have low rotor rpm, you can more quickly recover it by lowering nose or collective or both. Full touchdown autos were routine.

Haven't flown a Robinson, so I can't speak to that.
The voice of someone who has actually done it. Thank you.

Until I retired a year ago, the helicopter companies on the field were, every spring, usually training new-hires on their machines. They would do endless autorotations, all day, for weeks. It was fascinating to watch at first, then became routine. The first autorotations would transition into a hover, then they'd start landing. You'd hear the rotor RPM suddenly decay very rapidly as the pilot pulled collective in the flare and touchdown.

They never broke one.

The concern, I think, comes largely from people who have never done it, like some trike pilots who think taildraggers are vicious monsters, or who have never been in an intentional spin and so are terrified of the concept. We can thank those who have gone before and figured all this stuff out, sometimes at aweome cost, so we can be safely trained.
 
To me, it was FUN to do autos in the R22............and amazing. I never got a chance to fly anything else.
 
Just before I graduated flight school (a long time ago) at Mother Rucker, my young bride and I took a trip to Panama City. While cruising the beach, we saw a Bell 47G giving rides. Of course, we pulled over and bought a ticket. Very soon all three of us were putt-putting along on a sight seeing loop. On the way back, I told the white haired old pilot my wife had anxiety about me flying for worry what would happened if the engine quit. Could he please do an autorotation? Of course, he said. As we got a good sight picture on the little helipad, he slowly rolled the throttle all the way off. Down we came and gently touched down on some scrub sand adjacent the concrete, with a couple feet of slide. Just smooth as you please, smiling like the pro he was. See? I told my wife. No worries at all. Those were the days. Can't do that stuff now.
 
I fully believe at least 60% of my landings in flight school were autos to the ground...TH-55, UH-1, and OH-58...in the early 80s. A good UH-1 Pilot could auto to a lane and still have enough rotor rpm to pick it up and do a 180 degree peddle turn and set it down. The only power off landing that scared me were 50 ft hovering autos under NVG’s in the OH-58 Aeroscout course...we lost a few tailbooms to pilon whirl and that was a maneuver that was demo only soon after I went through flight school... AH-1 was easy as well. AH-64 was power recovery...and a discussion of how rare a dual ending failure was and how crash worthy the aircraft is....
 
It seems risk-averse bean counters have taken over in the military as well as some corporate. For the Army, I guess it's 'we have two engines in most aircraft' so no need. Autorotations are really not a big deal. Except for high hover of course. Low level 180 autos can get sporty, too, but that's part of the fun of it.

And autogyros fly in autorotation ALL THE TIME.:heli:
 
It's not just helicopters at risk. Practice forced approaches (PFLs) in fixed-wing airplanes sometimes end in the real thing, and sometimes it's not pretty. If the engine doesn't respond, you're into whatever you picked as a target. And and engine's failure to respond is almost always carb ice, or an engine that got too cold. Those are training problems, like most failures.

Preparation and a thorough understanding of all the stuff going on is necessary for safety. Until of course, we have self-flying airplanes and helicopters, and even then I have my doubts. Look at the fancy SUVs in the ditch next to an icy freeway; the ABS and SAS couldn't save the the drivers from their complacency. Self-flying machines will have their limitations, and many more, as well. A message will pop up on the nice colorful screen: "Autoflight is not responding. Close the program and restart the computer. This may take up to one hour."
 
I'd rather do helicopter forced landings for exactly the reasons you state above. Engine doesn't respond, you have minimal speed and easy landing. Fixed wing not so much.
 
It seems risk-averse bean counters have taken over in the military as well as some corporate.
And you can add the OEMs as well. As the Navy RFB for a TH-57 trainer replacement works its way through the system, Airbus believes it can convince the Navy full down autos aren't needed any more. While their entry, an H135, is the only entry to meet the IFR requirement, they are facing push back that the twin-engine 135 wouldn't be able to handle repeated full down autos. Will make for an interesting competition provided Bell's 407GXi and Leo's 119 can get FAA IFR certification before the RFB ends.
 
If a CFI is balling up a practice auto with power recovery, then they really don’t have the experience to be a CFI. Ft Rucker has been doing autos TO THE GROUND in TH-67s for 25 years without a single fatality. That’s literally millions of touchdown autos. Not even sure they had any injuries in all that time.

Now, are touchdown autos necessary? I don’t believe it’s required for CFI or COM now but it really depends on how much $$$ you have. The Army has allowed them (not much longer) because they can afford to ding up aircraft occasionally. That’s the price of training. Breaking tail booms on R22s at mom and pop flight school, not so much.

Practice autos to a power recovery? No way I’d want to fly with any helo pilot who’s never done any auto to at least a 10 ft power recovery. So many elements to the auto that must become second nature. You hear the engine spool down and low Nr go off. That must be an instinctive collective down reaction. Pitching for max glide / min ROD. Judging the flare altitude with the cyclic. How high to apply cushion with collective. At what point do you lower the nose. All of those stages must be ingrained so that it becomes second nature. It’s really no different than any EP (HYD off, FADEC fail), only that in an auto, you’ve got a little less wiggle room.

So yeah, if you’re gonna fly pax around in a helo, the PIC really needs to have some sort of auto practice with an experienced CFI. Just don’t smack your tail “stinger” on the ground on your check ride like I did! :eek:
 
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No way I’d want to fly with any helo pilot who’s never done any auto to at least a 10 ft power recovery
Do you know if it's required to demonstrate a full auto to the ground for the practical on a commercial rating?
 
Do you know if it's required to demonstrate a full auto to the ground for the practical on a commercial rating?

I believe it was removed a few years ago but not totally sure. My COM was thru military equivalency so I had no DPE practical.
 
From AOPA Autorotation article. "more accidents happen each year from practice autorotations than from actual engine failures. Surprise throttle cuts are especially critical because they can startle students and cause them to make sudden incorrect control movements. Inadvertently raising collective, pressing the wrong pedal or lowering the nose can drop the rotor rpm and risk stalling the rotor system. A student who simultaneously performs two or more of these movements could quickly stall the rotor system."
also see U.S. Departmentof Transportation Federal AviationAdministrationAdvisoryCircularSubject: Autorotation TrainingDate: 8/31/16AC No: 61-140A
 
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Lol! And imagine what would happen in real life if that future PIC had never experienced a real auto. Sounds like problem with incompetent CFIs. No way the situation should get that out of hand to stall the rotor. That’s just not maintaining positive control over your student.

Let’s not forget, an auto just isn’t an engine out EP. It could be required from a high speed shaft failure, loss of tail rotor thrust, fixed pedal, engine under speed, compressor stall, etc. Trying to do an auto to the ground with those emergencies when you’ve never even seen it to a power recovery, would be a disaster.
 
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Absolutely. Don’t know who in the FAA wrote the CFI test but they’re deathly afraid of helicopters.
 
On my first heli lesson (in an R22), I asked the instructor to demonstrate an autorotation (to a hover recovery). They are actually a lot of fun and you aren't dropping nearly as quickly as you would expect if you haven't ever done one. I do admit the recovery just above the ground is a little intimidating, but I'm sure like any other maneuver you get used to it.
 
I used to love doing power off 180 in my hershy bar wing Arrow to my airfield...with the gear down and 25 degrees of flaps everything except the last 100 ft was similar to a full autorotation in a UH-1...always put a smile on my face...but it not being ingrained in your head what to do when the engine noise stops and low rotor rpm goes off is insane...
 
I firmly believe removing practical items from training just contributes to @Ted DuPuis 's coined "common core piloting". This is the same as the FAA removing the spin requirements from PPL years ago. Now the FAA has more-or-less removed stalls from the ACS as well, requiring recovery only at the chirping of the stall horn.

The less we teach our students about the true envelope of flight, the less safe they're going to be. The answer to these accidents is NOT to teach less, because we're just going to breed worse pilots that have no idea what to do should one of these problems arise.

Less experience is NOT the answer.
 
I firmly believe removing practical items from training just contributes to @Ted DuPuis 's coined "common core piloting". This is the same as the FAA removing the spin requirements from PPL years ago. Now the FAA has more-or-less removed stalls from the ACS as well, requiring recovery only at the chirping of the stall horn.

The less we teach our students about the true envelope of flight, the less safe they're going to be. The answer to these accidents is NOT to teach less, because we're just going to breed worse pilots that have no idea what to do should one of these problems arise.

Less experience is NOT the answer.

Exactly. Our society is fond of dumbing-down curricula in the name of school safety and student "success," and so graduates go out and soon get into trouble in the actual, unforgiving world. They've acquired a confidence not supported by their mediocre skills. They didn't get what they paid for.
 
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Do you know if it's required to demonstrate a full auto to the ground for the practical on a commercial rating?
It was in the last century. I live about a mile from Spencer OLF. An out lying field of NAS Whiting. Students over there have always practiced autos with power recoveries. Makes sense. The Fleet only has multi engine helos. Students in Army Primary however were cleared to practice SOLO straight ins and 180s. (1960's) The FAA standard for SE or ME helo check rides is only to "Demonstrate engine out procedures."
As a 135 pilot, in SE Bell 206 varients, it was in an A/C equipped with Air Cruiser fixed floats. Every one, to the water. (also provided a good demo of Translating Tendency as you powered back up to 100%). In ME helos, check rides were not that different from a ME airplane.
BTW, FAA does not have a Float or ME class rating for Rotorcraft.
In my 135 helo experience, we did not see many if any screwed up autos. There were, how ever, a significant number of mishaps due to Vortex Ring State commonly called Settling With Power. Check rides always required demo-ing recoveries from VRS. These were done at least above 4,000' agl. Little comparison to doing stalls in a Skyhawk. I've done recoveries in 17,500 lb GW helos and usually see 6,000 FPM down on the VSI.
 
I firmly believe removing practical items from training just contributes to @Ted DuPuis 's coined "common core piloting". This is the same as the FAA removing the spin requirements from PPL years ago. Now the FAA has more-or-less removed stalls from the ACS as well, requiring recovery only at the chirping of the stall horn.

The less we teach our students about the true envelope of flight, the less safe they're going to be. The answer to these accidents is NOT to teach less, because we're just going to breed worse pilots that have no idea what to do should one of these problems arise.

Less experience is NOT the answer.
Exactly. Our society is fond of dumbing-down curricula in the same of school safety and student "success," and so graduates go out and soon get into trouble in the actual, unforgiving world. They've acquired a confidence not supported by their mediocre skills. They didn't get what they paid for.
I certainly don’t disagree with the fact that the FAA is dumbing down the training curriculum, leading to a production of pilots who are less capable of handling in-flight abnormalities than their prior generation counterparts.

However, I would be curious to know how many pilots who were trained off the PTS have been able to successfully recover from a stall during a critical phase of flight. I’m not so sure that the implementation of stall prevention, rather than stall recovery will make much of a difference in the accident rate, if any. Don’t get me wrong, I’m not trying to play devils advocate, because I’m in favor of stall prevention AND recovery as well as receiving spin and upset training, which also isn’t required under the current syllabus. I believe that if one is taught to prevent a stall, they’re more or less in the same shape as those who have been taught to recover from one, because the chances of one being able to successfully recover from an unexpected stall at low altitude <critical phase of flight> is slim.

<throws grenade, takes cover>
 
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it was in an A/C equipped with Air Cruiser fixed floats. Every one, to the water.
Of the 3 full autos I was "allowed" to accomplish, one was on water in a big-footed B model. Unfortunately, I don't think anyone on the Gulf does that anymore.
 
Students in Army Primary however were cleared to practice SOLO straight ins and 180s. (1960's)
Can confirm. Sadly my class was late 60s so I had to do mine after flight school incognito.

There were, how ever, a significant number of mishaps due to Vortex Ring State commonly called Settling With Power. Check rides always required demo-ing recoveries from VRS. These were done at least above 4,000' agl.
Fortunately, Settling With Power was part of my primary helicopter training. FAA heads would explode today if they ever saw one.
 
I firmly believe removing practical items from training just contributes to @Ted DuPuis 's coined "common core piloting". This is the same as the FAA removing the spin requirements from PPL years ago. Now the FAA has more-or-less removed stalls from the ACS as well, requiring recovery only at the chirping of the stall horn.

The less we teach our students about the true envelope of flight, the less safe they're going to be. The answer to these accidents is NOT to teach less, because we're just going to breed worse pilots that have no idea what to do should one of these problems arise.

Less experience is NOT the answer.

Could not agree more. All you have to do is look at some of the recent airline accidents -- Airbus pilots not recognizing a stall, for instance. It's crazy, or as Warlock says, insane. Welcome to the new age.
 
"From AOPA Autorotation article. "more accidents happen each year from practice autorotations than from actual engine failures. Surprise throttle cuts are especially critical because they can startle students and cause them to make sudden incorrect control movements. SNIP"
During the Vietnam war I was a helicopter instructor at the USAF helicopter school at SPS. We mostly trained experienced fixed wing guys in a transition to helicopters. Throttle chops were forbidden of course. But I had an older student who had been flying desks for awhile and he had only ever flow large multi-engine aircraft operationally. I would say "forced landing" and he would recite a complete checklist before he lowered the collective. One day, I had had enough, and at the end of the lesson, on our way back, I chopped the throttle. He recited the checklist, then we both watched the rotors slow down, horn blowing, until I panicked and entered the auto.

I gave him back the controls and quietly said, "in a couple more seconds, we couldn't have recovered, and would have died." Never changed and the school passed him. I hope he never had to do a real one.

I never did another throttle chop in the Huey.

Ernie
 
After reading all the posts in this thread, I am realizing that Army training in helicopters in days of yore was a rare privilege. Even PHI company checkout in the 70s did autos everywhere. Short final to the pad, 50 ft AGL? Throttle chop (nose forward, a few knots, put it in the water). Passing over a canal? Throttle chop.

How times have changed.
 
I can not imagine training without removing power from the rotor system and freeing the sprag clutch...being able to deal with a rotor over speed takes practice in the auto as well...particularly if maneuvering...as an MTP I spent many flights confirming the autorotation speed of the rotor and was part of the post phase test flight and anytime you worked on the head...also the only way to check the sprag clutch as well...
 
Great respect for MTPs. Might be the most responsible and demanding first line job in Army Aviation.
 
Why practice Autorotation in helicopters we loose more in practice than we would ever loose in the real event.

I've had one engine failure on a job in Alaska, and successfully auto'd with no damage to the helicopter. I am 100% certain that I would not have been successful if I had not done extensive training and continued practice whenever possible. That's why I practice autos.

I've had 3 hydraulic failures all culminating in non event landings where my passengers didn't even know anything was going on. Again I attribute these to training, and practice. That's why I practice hydraulics off.

I'm a firm believer in, if it can happen, you should practice for it if at all possible.

PJ
 
Back in the stone age, we did 15 minutes of slings and slopes and then spent the rest of the fuel load doing touchdown autos. Musta done 300 of them before checkride.

In nearly 9,000 helicopter hours, I've had one engine failure, but five transmission failures and one swash plate failure. Getting on the ground quickly is a good thing to practice!
 
Back in the day we used to do sling load autos with hydraulics off...with a tailwind both ways. ;)
 
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