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Entering autos: discussion split from Glasgow crash thread

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Old 13th Dec 2013, 17:56
  #81 (permalink)  
 
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I think most people are in denial about the levels of training that the collective ‘we’ enjoy!

I’ve had my share of ‘emergencies’ With the last adventure being a power rollback to idle (low side Gov) a couple of years ago in a heavy helicopter just as about to drop water in a tight valley and nowhere to go but up. The engine didn’t shut down but nor did it come back. When I listened to the CVR; I wondered who the two guys were, because it didn’t sound like me and my partner in crime.

Not one of my emergencies ever went according to the book, training or planning. But more on a slender touch of those things; and a large dose of divine providence.

It all happens so quickly that regardless of how well trained you might think you are? If you can’t train much more than operators currently allow?
You fall into the basket with the rest of us. Consistently lacking in ‘emergency training’ currency.

But I’m sure the accident pilot had his measure of training as per current regulations and I have no axe to grind there!

I’m neither an ace nor a sandbag. Just a consistent working pilot who has operated often in difficult conditions in many places around the world; and having flown multi crew with many nationalities, each with different basic training standards and cultural affect. These issues make little difference in the long game, Yank, Brit or Iranian. If we sat there poised waiting for the emergency we’d all need a shrink on a twice monthly basis from the stress alone?

We all try to prepare for when something bad happens, but we can’t maintain the effort for very long out of a 14 hour duty day and 8-10 hours flying.

What’s an insane/dangerous operation in the view of a charter pilot used to flying from an airfield to a big private house in the country; is daily bread and butter for a guy working a 205 or a B3 in Canada or wherever. Crap weather for me in a 212 slinging drills, is nothing for a guy in Port Harcourt during a strong Harmattan.

Look at the comments re: the guy slinging xmas trees with a 206 recently. My feeling when I saw it was of a a high time guy with good hands and feet.
I Just thought he was doing a great job considering it was a 206… I used to do it with a 500 and a Lama back in the day and declined to do it in a 206! Because I’m always scared of mast bumping when I get carried away, and you do get carried away, its great fun and one of the reasons we do it! It only seats one when slinging and it’s a fun job. Others took a more critical view.

No one’s objectively right or wrong! And many are swayed by the nanny states in which many people have been raised and then thrive in, perpetually rambling on about ultimate safety in helicopters. It’s always a brownie point if you call safety, even when talking out your ass!

Based on $$$ - not common sense, the industry thinks a trip to a sim or a line check or OPC every six months makes you current on emergencies…Bull****! We need to practice far more frequently than that but the game isn’t played that way unfortunately. We all live in a state of denial when it comes to our capabilities. If you don’t believe me, ask for a shaft failure with sound effects at TDP+5 + 5 next time you’re in the sim and see what happens. 9 out of 10 times you’ll screw up the first one or two; the big problem being that in real life there’s no do-overs!

I have no idea what happened in Glasgow and can’t begin to speculate. But at night low level in a turn! Anyone who could get away with an unexpected double flame out as an example, has more than most of us can muster…Sometimes an accident is just an accident and there’s nothing to say that the pilot was playing the game in any other way than the way he’d been trained and had approval for.

The drift into auto technique is shameful to read. How a bunch of people claiming to be seasoned pilots can think there’s a ‘one cure fits all’ - is one of the reasons I avoid whenever possible riding in the back of a helicopter.

I think that Proon should open a ‘closed posting’ section where you have to prove you’re actually an experienced helicopter pilot before you can post, as I’m sure some of the posters are imposters or inflating their experience beyond all reason. Many comments make no sense coming from seasoned pilots.

TC . I generally disagree with you as a principle of life, but I support you 100% in your comments here.

A note for any family or friends reading this forum.
I offer my sincere condolences and I’m very sorry for your loss! I didn’t know David and can’t think of a single thing to say that would ease your suffering. But he was in a bad situation and he did the best he could, maybe the best anyone could? …Sometimes the deck is stacked against you.
RIP David!
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Old 13th Dec 2013, 18:10
  #82 (permalink)  
 
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A couple more points - Pete backs up his advice with examples (mostly H500's if memory serves me right) where, following an engine failure the pilot(s) elected to dive towards the ground (pushing forward on cyclic) at the expense of rotor RPM. All of the examples showed very heavy landings on the left side of the machine due to lack of control due to low rotor RPM.

Having done quite a few HV demos in OH-58/Bell 206 to budding experimental test pilots, I can attest that in the high hover case, it's necessary to maintain a level attitude following the failure - mostly with a small amount of aft cyclic.

I remember hearing that during the HV tests for one of the Bell teetering rotor helicopters that the test pilot pushed forward on the cyclic when the (very) high hover point was first tested - his comment after several minutes of silence following the nearly vertical nose-down attitude that was observed was something to the effect of 'Don't push forward'.

On the other hand, don't be slavish - one US military helicopter training school used to insist on aft cyclic in a low altitude hovering engine failure when it wasn't needed.

Something else to remember is that real engine failures are not like the training ones- every single pilot I've talked to who has had a real engine failure in a single engine helo has commented on the very large surprise factor compared to training autorotations.
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Old 13th Dec 2013, 18:27
  #83 (permalink)  
 
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170' - great post!! The ending made me feel sad and slightly ashamed that I had really forgotten what this thread was all about.

DB
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Old 13th Dec 2013, 18:32
  #84 (permalink)  
 
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Very well said 170".


Shawn.....the "Surprise Factor" applies to Multi-Engined helicopters too especially if in other than Normal Operations that keep you light enough to fly around on one engine.

Load the Bird up doing Vertical Reference work in steep terrain sometimes as 170 mentioned where the only way out is UP.....and sometimes flight path restriction comes in the form of a raging Forest Fire.

All engine failures are not the same....it is one thing for the fire to go out....and another for it to go outside when a Power Turbine Wheel explodes and sends shrapnel all over the place.

Failures certainly are rarely straight out of the Check List or Ops Manual....and that is why it is hard to "train" for every eventuality.

When things go wrong....you do the best you can.

I once handled a Cockpit Hydraulic Fluid fed Fire, Utility Hydraulics Failure, and a loss of a tail rotor control pedal (physically lost the pedal from under my foot) while IMC with a Sling Load in Mountainous terrain.

The Checklist and prior Emergency Procedures Training did not cover that situation with much detail if any.

We did not look at the Checklist or actually conduct a single drill as laid out in the Manuals and SOP's.....but we handled the problems and recovered the aircraft to a safe landing zone.

Past Training helped structure our actions but being able to think our way through what we needed to deal with and set the right priority to it was the key.

That holds to performing an EOL or recovering from a single engine failure in a Twin.....you have to apply the right technique for the conditions you find yourself confronted with. There are some systems failures that demand nearly instantaneous reaction from the Pilot.....and certainly an engine failure on a Single Engine Helicopter is at the top of the list....as if Rotor RPM is lost then nothing good will happen after that.
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Old 13th Dec 2013, 18:40
  #85 (permalink)  
 
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To lighten the mood somewhat....the worst thing that has happened to me in a helicopter is ****ting my suit on the first leg of a double Brae. The worst thing I have done in a helicopter is complete those double Braes......without breaking the neck seal!!

DB
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Old 13th Dec 2013, 18:45
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I think the point Pete was trying to make is regardless of how much you "know" your brain is not yet engaged in the 1-2 seconds it takes to arrest the rotor RPM decay at high speeds.

To respond to a stimulus it must be detected by the senses, processed through the cerebral cortex, verified, and then muscles must move to respond, then the aircraft itself must respond. This whole process takes 4.6-5.0 seconds as confirmed by numerous tests in many countries including the UK. I may be able to dig them up if anyone is interested; they were cited in a Wirestike lawsuit I was involved in. The only reason pilots are able respond quickly enough with control inputs in a real sudden engine failure is exactly because they DO NOT use their brain, not the cerebral cortex anyway. A reaction can occur in just a fraction of a second, butr eactions must be conditioned, contingent.

If you teach as PG advised to make the aft cyclic part of your reaction then you can survive high speed engine failures. True, that on some engine failures below vy, it might be un-needed, or it’s possible it could even prevent you from getting to a better spot because you have slowed yourself to much.

The alternative however is to teach as TC suggested, to lower the collective and consider your spot which is going to take 4.6-5 seconds and in some highspeed engine failures that are truly surprises, time might not be sufficient to do that.

Pete has been teaching autorotations to experieced pilots for 35 years. He is one of the most highly respected instructors in the us, he is not over inflating his esperience.

Like many of you I agree, that it isn't that pilots do not know that at high speeds aft cyclic is required. If asked in a classroom they will all tell you that. What Pete's point is they dont do it when they need to because it has not been trained to be a reaction and he sees it person, likely daily.

I learned down and aft simultaneously, and then consider your spot and I believe that is the way to go.

(Edited to add the last paragraphs)


Last edited by 500guy; 13th Dec 2013 at 19:36.
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Old 13th Dec 2013, 18:58
  #87 (permalink)  
 
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The worst thing I have done in a helicopter is complete those double Braes......without breaking the neck seal!!


Errrrrr.....ahhhhhhh.....don't you mean the "Second Worst Thing"....as I believe breaking that Neck Seal would have been far worse than not.
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Old 13th Dec 2013, 19:07
  #88 (permalink)  
 
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FC80,
Sorry, age and a long day with the hot African sun burning my pink shiny helipad, combined with your surprised reaction, caused me to look at my last post and correct it - what I meant to say was that I never had an engine failure in a single, but I've had 3 double engine failures in twins . I was always taught that in forward flight I should simultaneously lower the collective with a touch of aft cyclic to prevent the nose dropping and use the flare effect to preserve Nr and prevent too much altitude loss, giving a few microseconds more to try and figure out how to get the beast down without killing myself. I guess it worked out for me because I survived and I always told my few students that watching their efforts at energy management helped me to learn that there are many ways to skin a cat. I had a few interesting single engine failures in twins which actually involved more problem solving and delicacy of control input than was ever the case with my own experiences of double engine failures. Anyway, what do I know, as I'm now reduced to reading what real aviators do
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Old 13th Dec 2013, 19:16
  #89 (permalink)  
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Originally Posted by John Eacott
Autos are energy management; you have three lots of energy (height, airspeed and Nr) to manipulate and arrive safely on the ground. How you manage that is dependent on many factors and there is no initial reaction that fits all of the possible entry scenarios.

Dogmatic posts such as the OP don't seem to have grasped that reality.
Exactly right (spot on?) regarding energy management. But I am more than a little sympathetic to the OP's point regarding autorotational training regarding disk loading and energy transfer in the autorotation entry which if I may- is the primary point attempted to be made- not airspeed, a separate energy variable that certainly has to be considered.

A sudden and complete power interruption at twice Vx/Vy is a very different experience than most training exercises and is complicated by surprise and shock, especially in twin-tin, as SASless points out. I am constantly shocked to hear otherwise competent pilots excuse poor decisions because "they have two engines". Double engine failures do occur, not to mention drive train and antitorque failures.
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Old 13th Dec 2013, 19:31
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Originally Posted by soggyboxers
FC80,
Sorry, age and a long day with the hot African sun burning my pink shiny helipad, combined with your surprised reaction, caused me to look at my last post and correct it - what I meant to say was that I never had an engine failure in a single, but I've had 3 double engine failures in twins . I was always taught that in forward flight I should simultaneously lower the collective with a touch of aft cyclic to prevent the nose dropping and use the flare effect to preserve Nr and prevent too much altitude loss, giving a few microseconds more to try and figure out how to get the beast down without killing myself. I guess it worked out for me because I survived and I always told my few students that watching their efforts at energy management helped me to learn that there are many ways to skin a cat. I had a few interesting single engine failures in twins which actually involved more problem solving and delicacy of control input than was ever the case with my own experiences of double engine failures. Anyway, what do I know, as I'm now reduced to reading what real aviators do
I was going to say - if you went into autorotation every time you had a single engine failure in a twin, you were missing a trick, old chap!

Anyway, the fact you're still here after a string of incidents like that surely attests to the fact you know what you're talking about!

DB - lucky you had one of the old style suits and not one of those fancy new ones with one-way valves under the epaulettes!
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Old 13th Dec 2013, 21:02
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170: Careful now...you're getting soft. Personalities aside - even some of the hardened crims in here are agreeing to what you and I profess. It makes sense, that's why. Hopefully the message is now delivered and you can go back to sticking pins in my effigy

DB: In case you didn't notice this thread has absolutely nothing to do with the Glasgow crash which is why the majority decided to split it off.
So no need for the sympathy vote bucco. PS, I am sure 170 will lend you some hat pins too
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Old 13th Dec 2013, 22:06
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I've been thinking about it and personally I don't think I have ever entered an auto without needing to pull back on cyclic . Also I was taught that as one tends to fly quite a lot with your hand away from collective it makes sense to start a flare immediately ( also my early flying was crop spraying where you certainly do not want to drop collective first !!!)...just because your hand is already there and it will buy you precious seconds of extra time in which to drop collective . As for which should happen first in a perfect world .... I'm not sure it really matters . If you keep the rrpm in , or just above the green it works for me .
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Old 13th Dec 2013, 22:18
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Funfly
The windmilling blades would be in the same plane of rotation as the powered rotor, so they would be affected by the same aerodynamic forces and stall at the same time.

There were experiments with ballistic parachutes as a recovery mechanism, but explosive bolts in the rotor head and large lumps of rotor blade falling away from the helicopter when the system was activated discouraged further trials.
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Old 13th Dec 2013, 22:25
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I learned my helicopter aerodynamics by reading the section in the AP3456.In that venerable document (Thank You, the UK MoD) the section on autorotation has the phrase "apply aft cyclic to restore Rrpm" Drummed into me since I was a baby pilot. Case closed and no big secret ,as far as I have been concerned.
The second thing I learned and have applied all my life while flying twins and singles is "linger not in the curve of the dead man ,lest the earth rise up to smite thee". I know there are good, well-paying helo jobs out there that require a high hover,but, for the rest of us, that would be a good rule to follow.
Finally, an instructor once made the comment that a good autorotation is judged by the entry not by the ending.He went on to explain that you can be over a football (or soccer) field or over an airport,but, if you screw up the entry after an engine failure, you will still end up dead.The other side of that coin is that you can be over a confined area and yet if you do everything right you will survive.Cuts and bruises and broken bones and a badly bent helicopter,but alive. Fair points,don't you think?
Alt3.
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Old 13th Dec 2013, 23:29
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Gouli,
Thanks for your reply to my question, on reflection I am surprised that you have not given me the reply I deserved for what was, on reflection, a fairly stupid idea. (and one that my embarrassment has required that I deleted!)

I think the question I was really asking is that there may be some way of offering additional security to rotary aircraft that operate low and in the vicinity of crowded areas even if this was at a cost to performance. I appreciate that it would generally be too low for a ballistic parachute to be practical.

I remember when ballistic chutes were first considered for fixed wing the general reaction was not positive for a number of reasons. Nowadays, however, they are accepted and the pilots using them no longer considered 'cissies'.
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Old 14th Dec 2013, 00:02
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Funfly
As a fixed wing pilot of very limited experience but a lot of theoretical knowledge, I have found this forum to be most informative about helicopter operation and hazards. Perhaps it would be technically possible to design a rotor head that would allow the blades to be angled sufficiently to unstall a stalled rotor disk given sufficient height. I don't think it would have helped in this particular incident. Perhaps a 'one shot' system with a small rocket fitted at the tip of each rotor could be used to bring a stalled main rotor back up to speed? The system need not be complex or heavy and the added rotor inertia could be advantageous. Not sure that health and safety would approve.
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Old 14th Dec 2013, 08:26
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TC - why do you always assume the role of self-elected thread policeman. Even when you are not talking technical bollocks you still manage to irritate me.

Actually, I guess on reflection this thread belongs to you seeing as it was your utter dismissal of Peters very competant post that generated this in depth discussion on Autorotations.

Now I am going to assume that you clearly know how to enter auto, in all stages of flight. Your subsequent postings demonstrate that.

However, had you given a little more thought to Peters post I think you would agree that the only practical and available method to restore a seriously decayed NR is to extract the energy from airspeed using the flare.

A flare is not an option at low speed/hover. This is precisely the point Peter is trying to make!! Now, just for once, read my post twice before you react, as you usually do, with arrogance personified!!

DB
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Old 14th Dec 2013, 08:40
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Goolie's rotor-tipped in-flight-autorotaion-restart-system:

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Old 14th Dec 2013, 08:44
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As a former fixed wing pilot, my real worry is a bunch of helo pilots arguing about how to fly a helo after an ehgine failure.
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Old 14th Dec 2013, 09:01
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Originally Posted by SLFool

Been done.
Quite so.

Indeed since the days of the Catherine Wheel!
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