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Entering autos: discussion split from Glasgow crash thread

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Old 20th Dec 2013, 21:28
  #441 (permalink)  
 
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FH1100:

The statement of yours that I identified is A STRAWMAN (look it up, you obviously don't understand the term) in that you dishonestly characterize a number of other poster's position with your own made up line of crap.

Your dishonest characterization, that they advocate moving the collective in isolation of other flight controls is YOUR STRAWMAN.

The amount of dishonesty in this thread, applied by any number of folks in the conversation, most likely comes from people passionate talking about a topic, with the shortcoming of being in broadcast mode only.

I don't think this is intentionally dishonest, in a malicious sense, but it is dishonest nonetheless to mischaracterize another's position.

I return to a fundamental concept of flying helicopters: you fly with both hands, and your feet.

Have a great weekend, all, and a Merry Christmas.
Santa Don't Hover
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Old 20th Dec 2013, 21:59
  #442 (permalink)  
 
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Agree, great post TET. This thread is otherwise a chore to read.

I am with the half who will not get a free beer from Peter. I believe the aft cyclic fixation is not appropriate and introduces a robotic response that is sometimes more dangerous than helpful. Re read TET's post for one example.

I do agree that it is appropriate in some circumstances, but the point is not ALL circumstances which is what is being offered up as the mantra. I do not understand the fixation on arguing with everyone about why it works and then only using examples where it is appropriate. FH1100's last post continues that methodology.

If you really need a simplification for a complex flight system that really does fit every scenario, in every emergency then try this:

NR is life. Maintain NR. Nothing else is more important.
The next most important is potential energy. Potential energy is airspeed and altitude (yes blade inertia too and some other factors, but keep it simple)

And to exploit this NR then potential energy system, sometimes aft cyclic will help. Sometimes it will not. Are we really not smart enough to train and learn which actions are appropriate in which circumstances?

Potential energy gives you ...well... Potential! And TET said it best, fly at height and speed wherever possible. I do. And those who want to always pull back on the cyclic first and earn a free beer from Peter had better REALLY make sure they do too.
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Old 20th Dec 2013, 22:18
  #443 (permalink)  
 
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Lonewolf:
The statement of yours that I identified is A STRAWMAN (look it up, you obviously don't understand the term) in that you dishonestly characterize a number of other poster's position with your own made up line of crap.
No I don't, Lone, and I'll thank you to stop putting words in my mouth. There are posters here who advocate lowering the collective FIRST after an engine failure. I'm not making this up and I'm not dishonestly characterizing their positions. Because I'm sure they genuinely believe it based on conventional wisdom.

Yet the NTSB clearly, unequivocally, in no uncertain terms tells us the importance of the order of tasks that need to be accomplished after an engine failure

Simutaneously:
1) Aft cyclic input;
2) Lower collective.

How much clearer do you guys need it to be? Must I spell it out for you? Hmm, it's already spelled out so that probably wouldn't even help. Do I need to read it to you more slowly perhaps?

Guys like TC say over and over that the FIRST response to an engine failure is to lower the collective. What guys like Pete Gillies and I are saying is that this is often a very, very WRONG thing to do, especially if you're in cruise at 500' agl or less. Ask the "Mosby" pilot if he'd like to reconsider that "collective-first" policy. Oh wait, you can't.
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Old 20th Dec 2013, 22:29
  #444 (permalink)  
 
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Seems to me Pete Gillies is trying to advise those pilots who are likely to kill themselves if they have a real engine failure because they won't act quickly enough. It's obviously most important for students - students need a method, not more "knowledge". Mantra?

The accident reports show it's not only beginners who cock it up, so maybe "knowing" what to do is simply not enough for everybody.

(Note: Airspeed (motion) is kinetic energy not potential energy, as stated above.)
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Old 20th Dec 2013, 22:43
  #445 (permalink)  
 
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Most of the time I agree, but Airspeed is also potential energy in a helicopter as it can be converted into NR.

FH1100, sticking to your guns. So, EFATO: cyclic back or collective down? Low speed bucketing, collective down or cyclic back?

Yes, am aware of the many times me cyclic back would work....but "very very often" and "always" are subjectively applied to support your otherwise good idea in certain circumstances.

I will stick to my guns too..... It is not an appropriate mantra to be robotically training helicopter pilots to do. It is a great skill to teach them to maintain and exploit potential energy after recovering NR.

Yes, I know I will not get a free beer from Peter - such is the price of my convictions.
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Old 20th Dec 2013, 23:01
  #446 (permalink)  
 
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Well, if "cyclic back" works 90%(?) of the time then wouldn't it be a good place to start? Just on the basis of statistics fewer lives would be lost, surely. (Those advocating this are talking about helicopters travelling from A to B.)

There are no perfect simple answers to anything and if you have no time to think a quick imperfect response is better than nothing. Talking generally.
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Old 20th Dec 2013, 23:05
  #447 (permalink)  
 
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it is appropriate in some circumstances, but the point is not ALL circumstance
Correctly said....but when dealing with those who are trying to type out a Cook Book.....with exactly one Recipe....that is what causes the problem.

Perhaps if we started a bit closer to the top.....say....."Maintain Nr within the Power Off Rotor RPM limits!".....all this arguing can be avoided.

As by doing that ....then we discuss how to accomplish that in all the varied situations that can occur....some of which can require quite different techniques.

I guess first we have to determine what it is we wish to do....what is it we are trying to accomplish....or avoid.

Is that too complicated?

To define the problem in very simple, clear, definite, unambiguous words?

The crux of the argument really is that for every situation one can give that application of Aft Cyclic would be the best move......I can offer up another where moving the Collective first is the best move.

With that in mind.....how do you "One Rule Fits All Cases" Thinkers respond to that?

Mind you I know one situation where my starting point does not apply!
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Old 20th Dec 2013, 23:14
  #448 (permalink)  
 
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So what is the percentage estimate where it becomes a bad idea?

A to B pilots may be the target market, but that was not specified in the brochure offered up, and still it does not address all their needs either.

And sometimes doing nothing is a much better idea than rushing into a solution with a patently incorrect reaction. The word is "sometimes". The problem with application of simple solutions to complex issues is that exceptions are inevitable......

.......hence the 1.5 billion posts on this topic which is really an attempt to apply a simple rule in the face of many exceptions. Even though it works in "very very very" many events and not in "very very" many others.
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Old 21st Dec 2013, 01:50
  #449 (permalink)  
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SASless asked:

"I would really like to know if only lowering the Collective while in a level Cruise at 116 Knots in a 350 during an entry into Autorotation and not moving the Cyclic will result in a 40 degree or more Dive.....it cannot be that complicated to find out!

Likewise.....how does one accomplish a 180 degree turn at the same time and ...and lose Rotor RPM....as it is going to be a steep turn from 300 feet in a screaming ass dive where one would assume there would be some G Loading on the Head that would tend to build RPM.....something you all insist G Loading shall do?

Any 350 Drivers willing to try......Devil 49....you fly those EC things.....what you think?"


I really don't know what would happen in that scenario. My experience is that the aircraft will yaw quickly right (vertical fin camber) and the nose will drop. A retreating blade stall as the NR decays would tighten up the action, I would think.

AMC does not do power chops at cruise, at least not in the AS350B2, due to the lack of a flight idle stop. The accident pilot may never have had anything but the 90 knot traffic pattern altitude training autorotative descents to a power recovery, a very benign, non-representative exercise.
We very rarely fly without medical crew so I can't take it out and throw it around the sky, either.

I would have to consider that this pilot was relatively low-time in the airframe. the hard right yaw and pitch down would be outside his experience base, it might delay recognition of an engine flaming out and the appropriate response. I would have though that a gun pilot would know about fast and low, and would have immediately pulled cyclic back, gaining the few extra seconds to avoid all the Kansas he was seeing in the windscreen the last five seconds of the flight...

Last edited by Devil 49; 21st Dec 2013 at 01:55. Reason: clarification
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Old 21st Dec 2013, 14:10
  #450 (permalink)  
 
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Devil,

The 135 based just south of me which supports a large hospital just north of me.....keeps whizzing by in cruise not much more than 500 feet.....and a Bell 407....might get up to 500 feet.

As they pass right over the house particularly the 135....I cannot help but worry just a bit about that in light of the Mosby and Glasgow crashes.

Do EMS Operators specify a "normal" minimum enroute altitude for Day/Night VFR Local Area flight?

I have checked my Home Owners Insurance and it would appear I am covered for damage to my roof by falling objects so I am not too worried should something happen while I am in the LZ Bar located in my basement.

So it is only idle curiosity and not with an intent to file a complaint that I ask. it is more to satisfy a question that arises when I see this happen.....as that altitude does not afford a great deal of cushion should something ugly happen....and perhaps Pilots set themselves up for extra problems by staying low rather than getting on up a bit.


This is the latest EMS Aircraft in the area....pretty thing!


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Old 21st Dec 2013, 21:17
  #451 (permalink)  
 
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Yes, I would be interested to see the results of all the R22 instructors in the world teaching their students to flare in the event of an engine failure rather than lower the lever....wonder if that would get sanctioned by the Robinson safety course?????

Wonder if anyone would be brave enough to do a throttle chop in a 22 having taught the student 'aft cyclic is the gift of life'and 'lowering the lever is a minor and secondary consideration'.
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Old 21st Dec 2013, 22:12
  #452 (permalink)  
 
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@crab - At the risk of muddying the waters, I attended the ‘Robinson Safety Course’ with Dick Sanford in 2008 and he explicitly stated (to an all-male and ostensibly heterosexual audience) that if you found yourself in an R22 in the cruise with your left hand enjoying the contents of your passenger’s blouse when everything goes quiet, then there was sufficient energy to manage with the cyclic (coning et al) to allow you to finish off what you were doing, remove hand and re-fasten buttons before finally lowering the lever. He said there was around 6 seconds of time. Everyone present asked him repeatedly to clarify this and he did so and was quite insistent that the famous 1.1 seconds could be extended massively in the event that the collective is not or could not be lowered immediately.

I have to say that this flies in the face of so much training to the contrary, and in the absence of any video evidence to prove it, then when the donkey quits I'm aiming to get the lever down quickly irrespective of what the cyclic might be doing.
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Old 21st Dec 2013, 22:27
  #453 (permalink)  
 
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OH MY! The Cat is smack dab in the middle of the Pigeons with that one!


One other source about the Safety Course that quotes Robinson about Entry to Autorotation and Energy Management....and quotes the 1.1 second number.

Robinson helicopter safety course


As it is a UK Source, we know it of course is impeccably correct.
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Old 21st Dec 2013, 23:32
  #454 (permalink)  
 
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For what it's worth, when I informally checked out in the AH-1G Cobra circa 1970 (long story, begins with a missive that started out "Your friends and neighbors...), it was made clear to me that if the engine quit while we were in cruise flight (which was pretty fast but to my surprise not as fast as a lightly loaded Chinook), I was not to immediately lower the collective but simply to keep the thing straight and level for a short while without moving the collective (exactly how long, I don't remember), wake up the pilot in the back seat, and then lower the collective. This suited my helicopter flying aptitude since I pretty much knew how to work the cyclic and pedals as a 1,000-hr fixed-wing pilot and flight instructor, whereas my response to a unexpected helicopter-engine failure from a collective standpoint was usually "Whut?" followed by a dawning realization that the sound of the rotor was changing. (That reaction time also stood me in good stead for engine failures in a hover.)
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Old 22nd Dec 2013, 01:07
  #455 (permalink)  
 
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Faster than a Speeding Motorbike

But - watch that rotor - the disc is always at positive aoa.

May I suggest that the flight phases are:

HELICOPTER FLIGHT
In forward flight disc at negative aoa

CATACLYSM
something breaks or stops

TRANSITION
from helicopter mode to autogyro mode.

AUTOGYRO FLIGHT
In forward flight disc at positive aoa.

The key here is knowing in advance what control inputs will effect the transition. In forward flight the disc aoa has to be quickly flicked from -ve to +ve and other normal control adjustments made. It is misleading to call this a flare. It isn't, it is just a quick flick to change attitude. It you sail or fly a wind-powered machine you will understand.

Yes, OK, I'm not even a novice, have never been anywhere near a real live helicopter, my interest is purely theoretical, so please feel free to tell me to "go away".

Thank you for your kindness and tolerance.

Best and most humble regards,
henry_crun
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Old 22nd Dec 2013, 05:03
  #456 (permalink)  
 
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[email protected]
said...

Wonder if anyone would be brave enough to do a throttle chop in a 22 having taught the student 'aft cyclic is the gift of life'and 'lowering the lever is a minor and secondary consideration'.


Crab,

Where did the OP say that the lowering of the collective was a minor and secondary consideration?? Or better yet, where did he even insinuate that??
It's silly to twist and distort a man's words.
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Old 22nd Dec 2013, 09:54
  #457 (permalink)  
 
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twice Crab i have been frightened in auto C&T. they bear the semblance of being too complacent with a semi experienced person, but then the crash comics are full of those stories with where two experienced, thought the other was driving.

1. a1500 hr careful, but self opiniated and quite strong pilot in a '47 3B1. i was further being complacent as we would all agree an easy auto machine. bear in mind i did this bloke LL/muster training, me, on the first auto of the check ride, "ok lets do a straight ahead, you fly I will follow, enter smoothly from 500' 60 kts". at 150' ol mate brings the collective up strongly to about half way, the throttle has been checked by me after a safe entry was done, in loud voice as, "throttle in over ride check."

2. an 1800 all on R22 pilot, new to me but supposedly mentored and trained by a couple of hotshots, was asking me at least twice during ride,"could you show me some autos?". this - i have learnt is a danger sign. i thinks to myself, self i better work out what this blokes knows first. hmmm. this young fella is mentally and physically fast. surely he has been taught the basic rules, yep ok let's see, catch him unawares, chop the throttle at 70 kts cruise power. yep nothing, i waited and waited, then roll throttle back on snapping the collective down and flaring, 82% good boy. next exercise, cup of coffee, long talkies, another hour of basics and simple autos, I simply must be sure he will react correctly before i let him go.

apologies for grammar punctuation, etc, iPads and me, we don't get along all that well.
tet.
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Old 22nd Dec 2013, 10:35
  #458 (permalink)  
 
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Autogyros aren't the same as autorotating helicopters, unless there's no thrust from their engine. While flying an autogyro might build respect for managing energy, perhaps like glider flying would for a fixed-wing pilot, what's done with a big propellor behind your back, and usually with no collective pitch control, isn't directly equivalent to balancing height and speeds to bring an unpowered helicopter (or autogyro) safely to Earth.
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Old 22nd Dec 2013, 13:46
  #459 (permalink)  
 
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IMHO I think SASless has bought some sense to this discussion by saying lets call it energy management.
Every scenario is different as are each machine, that is why we are pilots the " loneliness of command" we have to decide what to do and really it should be instinctive. Perhaps that is the problem , training. EOL's are always done by lots of schools I see from 70 kts over head the field straight into wind. Is this due to " most " instructors using the instructing role as a stepping stone to a better paid job. I have always found it quite perverse that the most inexperienced teach the new guys ???????
Doing an EOL from a hover at 500 ft compared to 120 kts is way different technique in energy management
Example in a 500 D in hover you have to dump the lever, which instantly causes a massive nose down attitude and will prevent a catastrophic loss of rrpm. This is actually helpful as it will bring airspeed up very rapidly ( yes I know it unloads the disc and increases rod) but that nose down attitude will mean very quick acceleration followed by a large rear cylic which will start to level the ship and bring back your rrpm. Tried doing it the other way round, all I can say is holy ****.
Now do it at 120 kts, close throttle slight right pedal, hold lever up and pull cylic back, ac actually climbed just but lost rrpm very very quickly as we got back to 60 kts. Better technique to lower lever about half way at the SAME time applying aft cylic ( rod 500 ft for about 8 secs). watch the rrpm and control airspeed and rrpm with collective. As airspeed decays to 80 kts ( best range speed ) gradually lower lever this will increase rrpm and gradually drop nose until you get to 60 kts ( best auto speed) by this time lever should be bottomed to gain as much rrpm as possible and to allow a stable auto and set you up for the EOL which again seems to have fallen off the must do things for instructors ( There is a difference in the mind to yes lets bring the engine in at the level stage, to put it down every time so the brain knows it can do it !!!)

Perhaps I will get my tin helmet on and dig a foxhole quick ..... incoming
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Old 22nd Dec 2013, 14:42
  #460 (permalink)  
 
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FN1100:
the NTSB clearly, unequivocally, in no uncertain terms tells us the importance of the order of tasks that need to be accomplished after an engine failure

Simutaneously:
1) Aft cyclic input;
2) Lower collective.

How much clearer do you guys need it to be? Must I spell it out for you?
.

Are you telling us that your assumption of this statement based on its order of presentation (1 then 2) is that this is how you enter auto ("in the cruise")?
Mustn't forget "in the cruise" because ALL of FN's arguments are predicated on "in the cruise"....ain't that right FN?
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