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Wisdom for low-level ops


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I see Rupert. So Larry wouldn't approve of the "screw" maneuver either? A 25% increase in power with a right pedal? You came off a ledge, started to sink and pulled MORE power? I also learned from extremely experienced pilots with plenty of medals hanging from their chests, but I'm not going to name drop. The fact that you didn't die is the same reason many of us don't die when we do something stupid in a helicopter; it's just not our time. That doesn't mean what you did was safe or should be written on this forum for young impressionable pilots to see. Keep the crazy maneuvers to yourself and nobody wants to listen to you brag.

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Matt, how do you think I came to give that advice?

 

1977 flying a Hiller 12B (note the "B" in 12B) I came off a ledge thinking I could make it over some downhill trees. I didn't. I began to sink before I got over the trees. I found myself below the ledge from which I'd started and below the tops of the downhill trees. As I pulled more pitch, with full throttle, my RPM began to decay, and with lower RPM, both main rotor and tail rotor, the ship began to slowly spin to the right. The little voice said to push in right pedal (yes, I have a little voice that talks to me...doesn't everybody?). An automatic 25% increase in effective power to the main rotor. The ship spun around a few times, I kept it level and I rocketed up above the trees and the ledge. Didn't die that day.

 

Same thing on power line patrol in Utah. Did you know some power lines go to 13,000 feet? I normally flew the G3B1 and the 206 for the company, and almost always the G3B1 for power line patrol. Didn't have the G3B1 that day, and since I didn't expect to land or hover at the projected altitudes, I followed my Chief Pilot's instruction to fly the mission in the 206. Observer on the left and pilot on the right. As we flew uphill of the line on our left at 13,000', I looked ahead and saw a line coming down to join our line, from above us (!). I tried to climb above the line ahead of us, but my ship just came to stop and I began to sink. I pulled all the power I had and tried to fly left over the line we had so far followed, and the ship wouldn't go left, but instead began to sink and slowly spin to the right. Guess what I did? Didn't die that day, either.

 

Larry Doll taught me to fly in the mountains way back when. The same Larry Doll to whom the HAI awarded the R. E. Trimble Award in 1984.

 

"Helicopter Association International in their 'Salute to Excellence' award have honored (R. E. Trimble's) memory every year at HAI with the Robert E. Trimble memorial award. This award is given to a qualified pilot who is especially distinguished in mountain flying."

 

I had ten hours of dual with Larry in the 13,000 foot plus mountains just to the east of Provo, Utah (part of my employment benefits, along with health insurance). I hope I haven't embarrassed Larry by using his name, but what he taught me saved my life a score of times in almost 50 years of flying helicopters (in all honesty, Larry probably wouldn't approve of my "screw" maneuver, as Matt phrases it). Thanks, Larry. Larry also taught me to fly long line in a G3B1. Try flying a long line at those altitudes while managing deck pressure. You know what "deck pressure" means? The fact that Chief Pilot Dan Nicholson would trust "a kid" with that machine meant a lot to me.

 

So, anyway, Matt, maybe you don't know as much about helicopters as you think you do. Just sayin'.

Retract my statement pushing right pedal would reduce torque on the aircraft.

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Well, Matt has something right: I have almost certainly

done more stupid things than he has. I can see I've learned a lot more, too.

 

A significant number of modern helicopters have relatively high numbers for sidewards flght, like 17 knots or so. This means the airframe, not just the dynamic components, has the ability to withstand a sustained 17 knot sidewards load. Twenty statute miles per hour. I know from experience that a spinning helicopter with NO tail rotor eventually stabilizes at a manageable rate of spin, and I think rate at which the vertical fin does not exceed a 20 statute mph side load. In other words, the airframe won't fail because of spinning, or, at least it hasn't failed with me. I don't know, though, whether the side load worries Matt or whether his ability to remain oriented in a spinning helicopter worries him.

 

I've ridden more than one helicopter to the ground, and one of them spinning. Spinning nose low, too. The whole gearbox came off. I never lost orientation. You, just stand up, now, and spin around on your own two feet. Can you keep track of direction? Hell yes.

 

RPM equals life. If you don't have RPM you have a high probability of bad things happening. If you have decreasing RPM because of power demands and you do not have the option of lowering collective, push in the right pedal. Stomp it to the stops.

 

Long line at 9-10,000 feet and the wind comes around behind you and you pull more power and the ship starts to spin, don't panic. Let it spin.

 

I worked with a respected pilot who experienced LTE trying to land at 11,000 feet. He lowered the collective and crashed on the LZ. Seriously injured. I don't know if he ever flew helicopters again. I don't want to second judge him now, but I wonder what life would look like for him now if he had maintained collective and reduced left pedal (pushed the right pedal) and gotten away from the terrain.

 

Matt, please describe the bogey man you fear. Helicopters don't come apart from spinning. A 1000 horsepower helicopter regularly has 250 horsepower of thrust going through the tail rotor already. Spinning against aerodynamic drag won't break the tail boom.

 

Scared you can't keep track of the horizon or your escape route? You can, believe me. Easy.

 

Doubt that an extra 25% power to the main rotor won't screw you up into the sky? It will, believe me. Easy.

 

As for bragging, I didn't intend to brag. I did enjoy reliving the experience from the safety and comfort of my on-the-ground chair. I did, though, want you to understand that I have a few hours at altitude, and I have worked with some highly credentialed mentors. I have since passed the number of hours and years of flying that my mentors had (I've out-lived my dad, too), and although some of them might not agree with me, now, that does not diminish the substance of what I have to say on this subject. Let the reader think for himself.

 

You think yourself too smart to find yourself behind the curve? Won't happen to you? Well, good for you.

 

However, if you find yourself in a low spot between a ledge and trees with decreasing RPM, or if you find yourself spinning with a long line at nine or ten thousand feet, don't give up. Do yourself a favor. Give your self a big boost of power to the main rotor. You will not get disoriented and the ship will not come apart.

 

You fly helicopters long enough you just do more and more stupid things. Human condition. You get to your late fifties and early sixties without killing yourself, you start doing fewer stupid things.

 

You junior birdmen out there WILL do stupid things. If one of those stupid things leads to decreasing RPM, settling for lack of power (not settling with power), LTE (spinning), etc. Don't give up. Don't lower the collective. You have a right pedal, Dude. God put that right pedal there for a reason.

 

Matt, Matt, what bad thing do you fear will happen if you push right pedal? What good thing do you fear won't happen? Do you doubt that the helicopter will go up with an extra 25% power? Do you doubt that you will ever do something that paints you into a corner?

 

I know some guys who fly offshore bus, and they will probably never experience LTE or settling. I flew offshore bus. 206's, 105's. Even flew a BV-107 offshore in a Part 121 operation. Part 121. What a hoot. Not the same as flying in the mountains.

 

Flying EMS as an old man, I could demand HOGE power or no-go. If I didn't have HOGE capability, I didn't do it. However, in the real world, where you make money with helicopters, sometimes you have to finesse it at the edges of performance. When you finesse it at the edges of performance, an unexpected light and variable wind blowing up your skirts can send all your smart planning and good intention tumbling down the side of hill.

 

Left-footed machine? Make sure you have a right down hill escape route. Starting to spin or losing RPM because you've topped out? Don't surrender. Push the stinking right pedal.

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Insufficient anti-torque available isn't the same as anti-torque failure. My limited experience is that the uncommanded yaw is much slower, not necessarily a threat to maintaining overall control, and is not always a forced landing/abort situation. Would you do a vertical climb clearing turn?

 

There isn't a black or white answer to the single challenge, except lack of planning, training and proficiency: that's pilot failing to accept personal limitations.

Edited by Wally
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Wally wrote "pilot failing to accept personal limitations."

 

How interesting.

 

Would Wally please list his personal limitations for us? Does Wally know his personal limitations? What do personal limitations look like? Do they even exist? This seems like a sound-byte type of thing to present yourself as an authority when you really have no idea what the words mean.

 

I understand physics. I get performance charts. Pressure altitude, temperature, engine performance, wind direction, in or out of ground effect: I understand those limitations.

 

Got a chart for personal limitations? Does it have a vertical and horizontal scale?

 

Wally mentions a slow uncommanded yaw. What does that mean? Did you just sit there watching it happen. Do you not have your feet on the pedals? What did you do to cause that, or not do that allowed it. Do you mean daydreaming while the nose of the helicopter wanders around?

 

Maybe I've done Wally an injustice. Perhaps he means nose drifting right due to loss of tail rotor authority due to low RPM. Yes, that yaw will start slow, and stay slow as the helicopter slowly settles into the side of the hill, shortly followed by a fire ball. Something like that happened to a good friend, whom I won't name. He blew the induction manifold off the engine and it no longer produced enough power to keep flying, without a loss of RPM. He slid his ship on to the side of a hill, but too steep for the helicopter not to roll downhill. Sitting on the downslope side of the helicopter, he jumped out and ran downhill as the helicopter gradually rolled over, burst into flame (gasoline, y'know), and rolled downhill after him, as if chasing him. Obviously, he outran the rolling fireball or I wouldn't know enough of the story to tell you the details. Anyway, if you don't have enough power you will lose RPM, altitude and tail rotor authority.

 

Let's get this low RPM thing straight. All normally-aspirated gasoline-powered piston engines have horsepower limits at given pressure altitudes and air temperatures. If you ask for more power than they will deliver at full throttle, their RPM will decrease. As their RPM decreases, they will typically (unless flown at a higher than rated RPM, which Hiller 12E pilots often did at high DA's) lose lift. In comparison, most turbine engines will continue to produce more horsepower, on demand, until they thermodynamically or mechanically self-destruct. We see exceptions to the self-destruct feature in almost all Huey-derived helicopters and in some of the earlier French Machines, which had hydro-mechanically programmed topping limits, and which would, at topping limits, lose RPM. Following the topping limit philosophy, most Bell Huey type helicopters get more efficient at around 96% rotor RPM, rather than at 100% RPM. I lost an engine in a 222 at close to gross weight on a warm spring day, and I can talk about low RPM and Low RPM audio. The low RPM audio doesn't stop unless you lower the collective. Anyway, if you ask for more power in a Huey-derived helicopter (maybe not the Air Force F model), your rotor RPM will decay to 96%, where it gets more efficient and gives you one last chance to pull your fat out of the fire. The 222? High speed running landing at local airport, both engines cooked beyond repair. Got an attaboy from my operator-employer and complaints from the flight nurse.

 

Radam mentioned RPM droop coming off the truck. Not the same thing. Radam means governor droop, meaning, Radam asked for power quicker than the governor could respond. Similar issue with 206L1's with the C28 engine: ask for power too quickly and suffer not only significant droop, but compressor stalls as well. Hear a bang? Means you cowboyed the collective.

 

Flying low level, not playing around but working in a piston-engined helicopter or with a turbine-engined helicopter with topping limits, requires attention to rotor RPM. Because, when we work low, we change directions and move quickly from one micro-meteorlogical system to another, and can easily find ourselves in a localized-micro-downwind situation despite a prevailing head wind. Happens to EMS pilots doing night recons of a scene: they judge their speed by ground reference and wind up below translational lift on the downwind portion of their recon. Gotta watch airspeed at night while doing a recon. This has bitten at least one EMS pilot badly. Led to settling with power at altitude. Hard, hard landing. Anyway, you get downwind and slow while working cattle or wildlife, and you unconsciously pull in power, not realizing that although flying forward over the ground you have begun to fly backwards through the air. Flying a topping-limited turbine and you may hear the low RPM audio; and, flying a piston-powered engine, especially one of those diabolically-undependable governed piston engines, and you may not notice anything until you start to settle and lose tail rotor authority.

 

Yes, tell me the above only happens to stoopid pilots who fly beyond their personal limitations and don't plan properly. Get real. Do this stuff for a living long enough and you'll invent stoopid things you never heard of. You'll do things waaaaay beyond your imaginary personal limitations.

 

On the good side, helicopter manufacturers have finally begun to put real engines in helicopters. They've also put in expert-system stability augmentation systems. When I first flew the EC-145 I realized the helicopter had finally arrived. What a quantum leap. You can take a brand new commercial pilot, right out of flight school, give him a week of ground school and half a week of flying, and he can work an EC-145 safely and effectively. Then it will take him another 40 years to learn to read winds and weather, but it won't matter, because he will have a real helicopter to keep him alive.

 

The latest helicopters from Eurocopter and Agusta have left the EC-145 standing in its own gut pile. Hallelujah Pilgrim. Anyone can now fly a helicopter for a living, even with personal limitations.

 

Yes, personal limitations. I had one of those, once. Took it to the vet and had him put it down. You should do the same (Did I just should on you? Sorry about that.).

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Oh boy, now we're moving toward that LTE monster. To pohii, Rupert said he "pulled pitch" which in a helo means more power. To Rupert, you're technique is piss poor. I never said your tail boom would snap off. Maybe I'm just a moron, but I didn't think my spinning helo was easy to control. Your story is suitable for the bar, not for this forum. Your advise is dangerous and is not a proven technique. A drooping rotor ( low rpm) is not the end of the world unless you react poorly. Lower collective, follow the nose and fly the helicopter. Have a plan.

 

Rupert, from your stories your obviously the best pilot in the world. Excuse me for trying to help pilots fly safer.

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I'm enjoying reading through the comments. Thanks to all of you taking the time to leave your thoughts!

 

Let me ask a couple more questions.

 

When I see videos of people maneuvering aggressively at low airspeeds and low altitude, it seems impossible to keep the wind on the nose, and difficult to constantly keep track of it if you're maneuvering (especially for something fast-paced like herding, or shooting/netting).

 

It seems to me like it'd be very easy, especially on a windy day, to

  • Put yourself in an LTE situation, whether due to low RPM, the natural wind not being on the nose, or side/rearward flight; or
  • Pull too much power and droop RPM leaving you almost no altitude which which to get back your RPM; or
  • Find yourself in an uncommanded descent due to decelerating or turning downwind while maintaining constant groundspeed (slowing airspeed)

All of those could happen fast, and catch you off-guard when you've got tunnel vision on the objective.

 

Any rules-of-thumb to prevent accidents from those scenarios? Other than "don't do it".

 

Any other situations likely to bite you, that I haven't mentioned?

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Hey pohi, when youre at the limits of your power and pulling power would slow down your rotor you don't pull in power. Thats common sense and is either something you have or not. You can learn how to manipulate the controls and not have common sense I suppose. Believe it or not there are other ways to climb in a helicopter. Maybe you missed that part of school.

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Matt sounds suspiciously like a non-pilot pretender. Wrong vocabulary Matt.

 

But just for the amusement value, what bad thing does Matt think would happen if he pushed right pedal in the situations I've described? Tell us about the danger of pushing right pedal. Specifics please. I discussed the tail boom thing because Matt had not specified a danger, and so I had to speculate as to his fears. And, for the record, Matt does not exhibit an iota of understanding regarding the high power low rpm situations I've described.

 

I think Matt has never flown a helicopter and has picked up just enough on this forum to pretend. No skin off me.

 

Kinda new here. Does anyone know if Matt actually has a pilots certificate?

 

And Matt, again, please share with us your "limits." You've brought them up several times now, but not told us about them. Limits please.

 

=====

 

How embarrassing. Going back and reading Matt's posts, I realize now I've gotten into a debate with a middle schooler.

Edited by Rupert
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Matt sounds suspiciously like a non-pilot pretender. Wrong vocabulary Matt.

 

But just for the amusement value, what bad thing does Matt think would happen if he pushed right pedal in the situations I've described? Tell us about the danger of pushing right pedal. Specifics please. I discussed the tail boom thing because Matt had not specified a danger, and so I had to speculate as to his fears. And, for the record, Matt does not exhibit an iota of understanding regarding the high power low rpm situations I've described.

 

I think Matt has never flown a helicopter and has picked up just enough on this forum to pretend. No skin off me.

 

Kinda new here. Does anyone know if Matt actually has a pilots certificate?

 

And Matt, again, please share with us your "limits." You've brought them up several times now, but not told us about them. Limits please.

 

=====

 

How embarrassing. Going back and reading Matt's posts, I realize now I've gotten into a debate with a middle schooler.

 

 

Rupert, I'm sorry I'm not a braggart like you. That's not what this forum is for so go somewhere else and tell the world how awesome you are. I'm not going to brag, sorry. My aim is to help, not insult, not hinder, not give poor advice. Think whatever you want about my experience and awards, it's not relevant to this discussion. You have an head so big I wonder how you squeeze into a cockpit, if you even still fly. My explanation and advise was sound for a dealing with low rpm in high da situations. I'm sure Larry would agree with my emergency actions that I posted, probably not yours.

 

Rupert, please keep your nonsense to yourself and try to help the next generation, not hurt them. If you can't figure out the dangers a pilot faces with a spinning helicopter in a high da environment close to the surface then you need to go back to school, maybe a better one than you went to before. Maybe for a hero like you its no big deal, the rest of us humans are not as perfect though. My emergency actions are common sense, have been taught for many many years, and are simple and easy to perform for even a low time pilot. Why can't you admit your error and learn from it? Are you that conceited? You're more worried about your illustrious accolades than you are about helping another pilot.

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Rupert,

 

In Matt's defense you came across as a total bragger. Your one story about escaping does not justify teaching that technique for a low power escape. It just doesnt. The technique saved your life but the conditions warranted that. There isn't one technique for every situation.

 

I honestly expect more from a so called experienced senior pilot then accusing people of not being pilots who disagree with your techniques.

 

To the OP, always be thinking about a low power escape, down and to the right, into the wind prefered.

 

Always have an out from any maneuver you are doing.

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I'm enjoying reading through the comments. Thanks to all of you taking the time to leave your thoughts!

 

Let me ask a couple more questions.

 

When I see videos of people maneuvering aggressively at low airspeeds and low altitude, it seems impossible to keep the wind on the nose, and difficult to constantly keep track of it if you're maneuvering (especially for something fast-paced like herding, or shooting/netting).

 

It seems to me like it'd be very easy, especially on a windy day, to

  • Put yourself in an LTE situation, whether due to low RPM, the natural wind not being on the nose, or side/rearward flight; or
  • Pull too much power and droop RPM leaving you almost no altitude which which to get back your RPM; or
  • Find yourself in an uncommanded descent due to decelerating or turning downwind while maintaining constant groundspeed (slowing airspeed)

All of those could happen fast, and catch you off-guard when you've got tunnel vision on the objective.

 

Any rules-of-thumb to prevent accidents from those scenarios? Other than "don't do it".

 

Any other situations likely to bite you, that I haven't mentioned?

 

-LTE just doesn’t happen. That is, the PILOT puts the machine in a condition which LTE occurs. If you AVOID those conditions, you won’t experience LTE…. Know what those conditions are and don’t “put yourself in an LTE situation”…… Also, understand the difference between low-rpm and LTE at altitude…..

 

-Prior to flight, know how much power you have. Once you arrive at your area of operation, confirm how much power you actually have. If you find yourself operating near the red-lines, reevaluate and/or reconfigure your machine to allow for a healthy margin of error….

 

-If you find yourself in an un-commanded descent, you’ve already screwed the pooch. Like mentioned above, maintain RPM. If you maintain RPM and have a healthy power margin, coupled with an escape plan, barring a mechanical malfunction, nothing should happen “un-commanded”…….

 

Don’t get “tunnel vision” and it’s not about “not doing it”. It’s about knowing what you are doing ala frame of mind based on judgment, experience and decision making…..

 

I will agree the level of industry knowledge, skill and experience is on a sharp decline and maybe, just MAYBE, it’s not a good idea to tell everyone on an internet forum how to react to a dire circumstance in a helicopter. With that being said, there seems to be an abundance of underlying concern with these questions to the point where I would suggest; those who are in fact “concerned” seek professional instruction from a reputable, power-management utility-type, of operator….

Edited by Spike
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Thank you Rupert for the read. This forum was getting pretty boring lately. I never got a chance to fly with Mr. Doll and people like him are becoming few-and-far-between in this business. With the expanse of the helicopter-centric safety-industry coupled with the warm and fuzzy ab-initio flight instruction, check-list driven, button pushing, risk adverse decision makers, the pussification of this industry will be complete in a few years. Specifically, the highest accolades this industry can bestow will be given for the “safest” operation which is the one that never pulls the helicopter out of the hangar…..

 

To wit, during my initial commercial training, the “right pedal” recovery was a technique taught by the school….. Since then, I haven’t needed to use it to save my ass in a near death event but, I have used it to provide me with an additional margin of error….. Lastly, like you said and I can attest as well, every situation is different. Simply lowering the collective and lowering the nose to gain airspeed may not be an option…….

 

In the end, don’t fight the machine…. Right pedal and fly away….

 

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I was trying to find that video. That video should be shown at every school! Lowering collective, losing altitude and trying to gain airspeed would've most likely ended up as a $25 million dollar insurance write off...

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Ruperts 'corkscrew' technique has already been discussed.

 

http://helicopterforum.verticalreference.com/topic/16907-myths-and-crosswinds-and-know-it-alls/page-2?hl=spin

 

At that time he believed it was an acceptable solution to dealing with LTE. I will still firmly argue that it's not.

 

What he is describing now is an emergency situation where the pilot got behind the aircraft and is experiencing low RPM while at low airspeed and low altitude. Consequently, the aircraft will begin to settle while starting to rotate (do the decreased efficiency of the main and tail rotor). In this situation, reducing collective (to restore RPM) will result in a collision, as there is not sufficient height above the ground for a recovery. The only other option would be to reduce anti-torque (less left pedal in an American machine) to restore RPM. With RPM restored, you can maintain altitude and directional control.

 

However, there is a huge difference between reducing anti-torque to initiate a gentle turning climb and kicking the right pedal to the mechanical stop and spinning uncontrollably.

 

As I mentioned in the last discussion, full torque pedal puts you at negative tail rotor pitch, which still eats up available power with the additional disadvantage of accelerating your rate of yaw. The technique that Rupert is describing requires a smooth reduction in anti-torque, but by no means should you apply full torque pedal.

 

'Corkscrewing' w/ full torque pedal applied is bastardizing a legitimate technique that requires a lot of finesse, and is not simply done by just kicking the pedal to the stop. Teaching it that way is a disservice to our industry, and is creating a huge misconception among less experienced pilots.

 

 

 

 

 

 

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Wally wrote "pilot failing to accept personal limitations."

 

How interesting.

 

Would Wally please list his personal limitations for us? Does Wally know his personal limitations? What do personal limitations look like? Do they even exist? This seems like a sound-byte type of thing to present yourself as an authority when you really have no idea what the words mean.

 

I understand physics. I get performance charts. Pressure altitude, temperature, engine performance, wind direction, in or out of ground effect: I understand those limitations.

 

Got a chart for personal limitations? Does it have a vertical and horizontal scale?

 

Wally mentions a slow uncommanded yaw. What does that mean? Did you just sit there watching it happen. Do you not have your feet on the pedals? What did you do to cause that, or not do that allowed it. Do you mean daydreaming while the nose of the helicopter wanders around?

 

Maybe I've done Wally an injustice. Perhaps he means nose drifting right due to loss of tail rotor authority due to low RPM. Yes, that yaw will start slow, and stay slow as the helicopter slowly settles into the side of the hill, shortly followed by a fire ball. Something like that happened to a good friend, whom I won't name. He blew the induction manifold off the engine and it no longer produced enough power to keep flying, without a loss of RPM. He slid his ship on to the side of a hill, but too steep for the helicopter not to roll downhill. Sitting on the downslope side of the helicopter, he jumped out and ran downhill as the helicopter gradually rolled over, burst into flame (gasoline, y'know), and rolled downhill after him, as if chasing him. Obviously, he outran the rolling fireball or I wouldn't know enough of the story to tell you the details. Anyway, if you don't have enough power you will lose RPM, altitude and tail rotor authority.

 

Let's get this low RPM thing straight. All normally-aspirated gasoline-powered piston engines have horsepower limits at given pressure altitudes and air temperatures. If you ask for more power than they will deliver at full throttle, their RPM will decrease. As their RPM decreases, they will typically (unless flown at a higher than rated RPM, which Hiller 12E pilots often did at high DA's) lose lift. In comparison, most turbine engines will continue to produce more horsepower, on demand, until they thermodynamically or mechanically self-destruct. We see exceptions to the self-destruct feature in almost all Huey-derived helicopters and in some of the earlier French Machines, which had hydro-mechanically programmed topping limits, and which would, at topping limits, lose RPM. Following the topping limit philosophy, most Bell Huey type helicopters get more efficient at around 96% rotor RPM, rather than at 100% RPM. I lost an engine in a 222 at close to gross weight on a warm spring day, and I can talk about low RPM and Low RPM audio. The low RPM audio doesn't stop unless you lower the collective. Anyway, if you ask for more power in a Huey-derived helicopter (maybe not the Air Force F model), your rotor RPM will decay to 96%, where it gets more efficient and gives you one last chance to pull your fat out of the fire. The 222? High speed running landing at local airport, both engines cooked beyond repair. Got an attaboy from my operator-employer and complaints from the flight nurse.

 

Radam mentioned RPM droop coming off the truck. Not the same thing. Radam means governor droop, meaning, Radam asked for power quicker than the governor could respond. Similar issue with 206L1's with the C28 engine: ask for power too quickly and suffer not only significant droop, but compressor stalls as well. Hear a bang? Means you cowboyed the collective.

 

Flying low level, not playing around but working in a piston-engined helicopter or with a turbine-engined helicopter with topping limits, requires attention to rotor RPM. Because, when we work low, we change directions and move quickly from one micro-meteorlogical system to another, and can easily find ourselves in a localized-micro-downwind situation despite a prevailing head wind. Happens to EMS pilots doing night recons of a scene: they judge their speed by ground reference and wind up below translational lift on the downwind portion of their recon. Gotta watch airspeed at night while doing a recon. This has bitten at least one EMS pilot badly. Led to settling with power at altitude. Hard, hard landing. Anyway, you get downwind and slow while working cattle or wildlife, and you unconsciously pull in power, not realizing that although flying forward over the ground you have begun to fly backwards through the air. Flying a topping-limited turbine and you may hear the low RPM audio; and, flying a piston-powered engine, especially one of those diabolically-undependable governed piston engines, and you may not notice anything until you start to settle and lose tail rotor authority.

 

Yes, tell me the above only happens to stoopid pilots who fly beyond their personal limitations and don't plan properly. Get real. Do this stuff for a living long enough and you'll invent stoopid things you never heard of. You'll do things waaaaay beyond your imaginary personal limitations.

 

On the good side, helicopter manufacturers have finally begun to put real engines in helicopters. They've also put in expert-system stability augmentation systems. When I first flew the EC-145 I realized the helicopter had finally arrived. What a quantum leap. You can take a brand new commercial pilot, right out of flight school, give him a week of ground school and half a week of flying, and he can work an EC-145 safely and effectively. Then it will take him another 40 years to learn to read winds and weather, but it won't matter, because he will have a real helicopter to keep him alive.

 

The latest helicopters from Eurocopter and Agusta have left the EC-145 standing in its own gut pile. Hallelujah Pilgrim. Anyone can now fly a helicopter for a living, even with personal limitations.

 

Yes, personal limitations. I had one of those, once. Took it to the vet and had him put it down. You should do the same (Did I just should on you? Sorry about that.).

 

Would Wally please list his personal limitations for us?

64. Exactly 64. 63 is fine and 65 is unacceptable. That number doesn’t mean anything, does it? Neither do fixed personal limitations.

Happy with ‘64’? I’m not because there are very, very few factors that I consider unsafe with a single presentation. Icing is about it. I might operate in some environments in some equipment in some conditions, for instance: 300 and 2 and a favorable weather trend in operating a 2 bladed Bell, light, in open terrain where a forced landing was not an issue. A host of other factors increase weather minimums- population, vertical obstructions, open water, distance between airports, weather, fuel, performance limitations. I have to KNOW that issues have acceptable comfortable alternatives.

 

Does Wally know his personal limitations?

Yes.

 

What do personal limitations look like?

Paraphrased, Wally won’t do it if it seems like it will be too much like work.

 

This seems like a sound-byte type of thing to present yourself as an authority when you really have no idea what the words mean.

Wally charges more for specific authoritative advice. This is the internet and worth every penny. If you’re not smart enough to keep within your training and experience...

 

Got a chart for personal limitations? Does it have a vertical and horizontal scale?

Nope, it’s absolutely go/no go.

 

Wally mentions a slow uncommanded yaw. What does that mean? Did you just sit there watching it happen. Do you not have your feet on the pedals? What did you do to cause that, or not do that allowed it. Do you mean daydreaming while the nose of the helicopter wanders around?

 

I have encountered anti-torque limitations and failures.

 

The anti-torque thrust failures spun quickly and accelerated until power was eliminated. I don’t believe I could fly out of those situations. Maybe test pilots or others who have trained in the maneuver could, but I wouldn’t try it.

 

The anti-torque limits were anticipated and dealt with by cross control, or aborts and changing the plan. They did not spin quickly, but again, I anticipated and had a plan.

 

I have encountered power limits that resulted in rotor decay. If I reduced TR thrust demands, it was to establish a climb in the space available with limited yaw.

 

I have done ascending clearing turns in a hover. I controlled the rate of turn to a point of comfort.

 

Which starts to get to the point- a yaw is a yaw, and an uncommanded yaw is not necessarily an emergency. You deal with yaw changes constantly at a hover and don’t abort because the nose twitches a degree or two. If I powered out, bleeding RPM but stable in yaw, I can see reducing TR thrust to a point that arrests any descent. If that was a comfortable rate of yaw, why not reduce the TR thrust and establish a climb, still in an otherwise controllable yaw until you’re above the terrain threat? (Train and practice this before you accept this as an option! Okay, Rupert?)

"Know thyself" and the proposed operation, respect your personal limitations as the particular situation demands, err on the side of caution. KNOW!
Edited by Wally
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I think neither Matt nor Wally have ever made a living flying a helicopter, and in fact may never have even flown a helicopter. Maybe had a ride in one.

 

As for bragging, I gave specific examples of real events for the purposes of illustrating my case, whereas Matt and Wally simply attacked my person. I don't think they know anything more about helicopters than they have picked up from pretending here. No insult intended. I just don't see how a working helicopter pilot can have so much fear about helicopters.

 

VR Member says they taught the technique in his school. He doesn't seem very afraid of it.

 

If you fly helicopters long enough, you'll find yourself in situations you never imagined. Given today's powerful helicopters, you probably won't see a right spin due to RPM decay, but you might see a right spin for other reasons, especially if you fly long line. Just don't let it scare you. The ship will not spin so fast you can't keep track of direction, and, if you need it, you can give yourself a lot more power by pushing the right pedal to the stop. Typically, full right pedal simply means no left pedal and maybe two degrees tail rotor blade pitch in the direction of right pedal. Hardly any nose right thrust at all. Mostly a discontinuance of nose left thrust.

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As a military guy turned civil government pilot, apparently I don't live close enough to the edge. I like my expensive turbine-powered toys and the fact that my employers allow me to make no-go decisions before the point I where I have to apply opposite pedal to escape (flying my backwards European helo I have to think in reverse now). I did enjoy the discussion of pilot techniques before it turned into a pissing match.

 

There are the book solutions and there are some pilot solutions that one can keep in their hip pocket for when they're needed.

 

The most important lesson is to alway leave yourself an out. If there's no out available, then you'd better consider how to get out of this situation. If you have to get yourself into situations where there is no out, then in my opinion, someone's life had better be on the line. No paycheck is worth that sh*t otherwise.

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I think neither Matt nor Wally have ever made a living flying a helicopter, and in fact may never have even flown a helicopter. Maybe had a ride in one.

 

As for bragging, I gave specific examples of real events for the purposes of illustrating my case, whereas Matt and Wally simply attacked my person. I don't think they know anything more about helicopters than they have picked up from pretending here. No insult intended. I just don't see how a working helicopter pilot can have so much fear about helicopters.

 

VR Member says they taught the technique in his school. He doesn't seem very afraid of it.

 

If you fly helicopters long enough, you'll find yourself in situations you never imagined. Given today's powerful helicopters, you probably won't see a right spin due to RPM decay, but you might see a right spin for other reasons, especially if you fly long line. Just don't let it scare you. The ship will not spin so fast you can't keep track of direction, and, if you need it, you can give yourself a lot more power by pushing the right pedal to the stop. Typically, full right pedal simply means no left pedal and maybe two degrees tail rotor blade pitch in the direction of right pedal. Hardly any nose right thrust at all. Mostly a discontinuance of nose left thrust.

 

Rupert

Class 69-17

Vietnam Aug 1969 thru August 1970

Fort Wolters IP

Various non flying jobs

CFI

PHI Feb 1983 thru Mar 1997, singles, light twins, ATP (I paid for it, not PHI) then IFR mediums

Stay at home father for first 4 years after my youngest son's birth

HEMS since June 2001

 

I've done sales, management, manufacturing, and non-profit... and 37 of the last 48 years flying professionally.

 

11,500 flight hours

1150 night, 400 of which were 'in country', unaided, and about half of that nap of the earth. At. Night. Unaided.

8700 logged cross country

More than 60,000 logged landings... I didn't start counting landings until PHI.

No long line or other utility work and no aerial application.

 

P.S. If you demand more than turbine's max output, you will get rotor droop, usually preceded by an N1 over-speed or over-temp.

Edited by Wally
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Have to say I am on Wally's side.

 

Similar background of military, first solo 1969, with 15,000 hrs since then.

 

Never, ever have I reached an aircraft limit that I wasn't ready for. Never had an uncommanded yaw, because I am always aware of where my left foot is and how much remains and how fast I am using it up - nose over, fly away, think about it.

Never got so loaded up that the revs drooped.

I have limits, and they are black and white, go/no-go. The bosses sometimes are not happy when I declare a limit that I will not exceed, but that is due to their ignorance of the situation.

The more experience you have, the easier it is to see a limit approaching - the junior guys have not seen it yet and are in the "wtf??" mode.

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