R44 down Rio de Janeiro
 

a video : G1 - Helicóptero cai e deixa 4 feridos na Região dos Lagos, dizem bombeiros - notícias em Rio de Janeiro

a good place for a soft crash eh

Quite a rare but instructive video of how quickly LTE bites if the chopper is slow and the wind is wrong and there's very little height to recover from except try and do one or more of the following:

1. closing the throttle and reducing collective
2. "milk" the collective
3. flying into the direction of the turn
4. doing an auto once there is any airspeed
but I think none of these would work for this poor guy.

It's all very easy to say one should never get oneself into this position but what other escape methods does one have ? I'd be keen to hear from anyone who has done extensive research into this area (as I have) or has been through a similar situation.

Thanks in advance.

Dangerous mis-understanding
 

LTE (Education) - LTRED

Presuming there was no mechanical fault (loose article in control run?)

This appears to be a classic case of 'the education problem'.
I hope no-one was injured.

The Airspeed becomes negative (due to the classic accidentally downwind app)

The weathercocking is unexpected
a small and timid input is ineffective
the pilot becomes confused
despite the input he has made the helicopter appears to be responding in the wrong direction.

The pilot makes drastic and confused control inputs and sometimes crashes.
- most pilots suffer this educational stage at some point and learn to be authoritative.

There are many examples of this (class) of accident/incident (LTEd):
Australian film pilot (looses 2000ft whilst confused)
Irish wedding squirrel
EC120 Redhill (more or less)
Gazelle in Yorkshire (fatal)


The R44 does not run out of pedal at zero A/S - you just need to use the pedals.
At Airspeed the situation is improved - with the worst pilot screw up the most you'd have to turn is 180 deg.....
- the action suggested by RF might be a little drastic for a serviceable helicopter, where the pedals just need 'subtle manipulation' to arrest yaw.

Crash landing in a fairground and on top of an inflatable slide!



Mickjoebill

Thanks AnFI for your input. As a matter of fact, I agree with your comments:

You control it, and not the other way.

that is true too, and if all else fails, try my aforementioned "drastic actions" !

Cheers.

I don't know if I would close the throttle. Lower the lever sure.

R22LTE
 

I got into it at 400 agl(photo flight), completely my fault. := I WAS trying to stay above 20 kts, but I failed to do that. Spun 3 times in 3 seconds, full left pedal, and it felt like I was holding a tiger that wanted to break free. Fighting to keep it from spinning, with full left pedal, and that sorta worked, pulled a bit of collective, got a low RPM horn, OK that didn't work, down collective, while fighting the pedals again, tail rotor sounds like I had never heard before, nosed it over to get forward airspeed, with no response, nosed it over again to about a 60 degree down angle, yawing back and forth, and finally got it back at 50 agl over the beach. Got out of the 22 10 min. later at the airport, and the seat was still attached to my behind! THEE LONGEST 15 SECONDS OF MY LIFE. My photog hit my knee and said GOOD JOB, that was FUN! IF he only knew!

What would you say would be the main reason for losing tail rotor control in your case?
Was it 20kts downwind or reducing airspeed to possibly being in the negative? Did you make large collective inputs due to losing ETL (with big change in torque as a result) with feet not being able to follow?

Happy to learn,
Helldog

Yes, for me 20-23 kts airspeed would have been ideal....
 

The wind was at my 8 O Clock, and I knew it was there, that's the part that bugged me, I knew it was there! BUT my attention to trying to slow down too much in order to get the shot, and not fly the helicopter the way I should've been! It's a natural habit, as that you're starting to slow down with cyclic, you'll automatically pull a bit of collective, at the time though, maybe 20 inches MP, I was at sea level, and a very cold day for SoCal. There was honestly, a two beat, from the time I dropped below 20 kts, to when the helicopter yawed a bit to the right, then BAM, spun 3 times in a blink of an eye. I was behind the helicopter the whole time, I had to react to it, rather than vise versa.

Unless I am directly into the wind, will I drop it below 20 kts forward airspeed to get a shot. I know I introduced it to myself, and I've since forgiven myself for it, but I will never forget that experience, and lesson learned! Hope this helps!
Rob

it doesn't look like a TR failure...

Flag in background appear to support the LTE. Brisk wind away and slightly to right of camera. The acceleration and deceleration of the turns. Interesting 'high pitched' whine down just at onset of spin. Pilot induced?

That low over people? Duh!

Full left pedal, lower collective to gain airspeed and reduce torque in the altitude you have. Not much option. In fact, don't be there in first place is only option.

Sorry for the kids who didn't get their turn on the bouncy castle.

Why would you want to close the throttle? dropping the collective would be reducing the torque. correct me if i'm wrong, but theres no need to completely close the throttle to get out of LTE. I would prefer to keep the engine completely online in a situation like this.

Apologies for regurgitating the FM. At the rate of rotation in the video, there is no need to close the throttle. Agree.

I don't think the first mention of 'close the throttle' (ReverseFlight) was that carefully thought through. Or at least I hope not.

The idea is of course to REDUCE TORQUE. If that means reducing pitch, you must lower collective, which in turn should be accompanied by an appropriate closing of the throttle.

However, it is important that the 'throttle' is not the cause, and so cutting the engine completely is NOT necessary. More importantly, and Rotor RPM droop will result in tail rotor RPM droop. This is undesireable. Keep RPM up.

LTE recovery is simple and systematic.

ReverseFlight, for someone who has done much research, your recovery list appears somewhat confusing...or could be for beginners. I think I understand your points, but better to stick to the basics. If going into detail, then provide an explanation....I envisage some newbies 'chopping the throttle' based on your No. 1 suggestion!

*Edit* - You say your 1-4 response is regurgitating the FM? Is that really what the R44 manual says? I'm surprised. FAA certified aircraft!


FAA Advisory Circular - AC 90-95 - Unanticipated Right Yaw in Helicopters

So this guy is about 40-50 feet up in LTE with nil airspeed and you think lowering the collective will save his aircraft.
Ah ... so the FM implies there may be situations where lowering the collective is futile or highly dangerous (from the video I'd say it's 50 feet with nil forward airspeed).
Read my post carefully. If you can find these in the FM, let me know.

Cheers.

Use the controls for their purpose....
 

He only needed to move the left pedal forward ... to prevent the rotation to the right.

The R44 does not run out of left pedal - but pilots do get confused - as is clear from this thread..... many questionable solutions proposed here.

Most pilots learn this - most often by being caught out, and then becoming more authoritative.

There are many accidents from this cause - the fatal Gazelle accident in Yorkshire was most probably an example....

ReverseFlight,

Dude. You listed four recovery actions. One of them was 'closing the throttle'. While your post explains that these are 'beyond' the recommended techniques for use in low altitude / airspeed situations, you clearly caused some confusion for others. Some people asking why the 'throttle must be closed'.

Instead of explaining and clarifying your list, you replied with what I can presume was an attempt at poorly written sarcasm, which caused more confusion. I think you'd better read YOUR post more carefully.

The recovery techniques I listed (in italics) were directly copied from the Rotorcraft Flying Handbook, a training book. Not the FM. You will also find the same recovery technique listed in the FAA Advisory Circular 90-95.

You'll note that those techniques therefore state a complete recovery chain, rather than scenario specific actions. It also provides warnings regarding LTE at low altitude.

Since it is important to keep the entire section together, so no one can take any part out of context (as you have done), I'll repost it all here.

It is important that the steps above are learnt as the recovery techniques. They may have saved this pilot alone. Step 1 - APPLY FULL LEFT PEDAL!

If you have other techniques from dusty old videos, then be very clear, or you'll have people less learned than you closing throttles and milking collectives when all they need is APPLY FULL LEFT PEDAL.

cl12p2s

cl12pv2s
 

can I double check that with you...
you don't mean the pilot should partially close his twist grip do you?
I think you must mean(?): "....and the correlator will close the throttle (butterfly valve) by the appropriate amount - reducing the torque but leaving the RRPM unaffected." ???

AnFI,

Yes, that is exactly what I mean. In an LTE situation, RPM must be maintained, but power reduced.

Lower the collective, and maintain RPM.

Someone else might chip in more, but that's how I learnt it.