Helicopter Down FL

Kenny Phillips said:
looks sort of like an un-arrested autorotation,
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For some models there's nothing to "arrest" it except mother-earth. Looked like he did his pilot thing rather well. Too bad it wasn't to dry land.
 
The R44 has fairly benign autorotation characteristics. In this case however, based on the video, the sink rate seems high and the flare poorly timed. Maybe RRPM got too low. I’d be curious to see the preliminary report.
 
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It looked completely out of control to me. I'd have thought he could have made a better attempt to miss the swimmers and do even a LITTLE auto. But WTH do I know. I got my rating in an R22.
 
My guess is that the pilot was flying low and fast along the coast, and when they had a problem, there wasn't sufficient time to lower the collective, pitch for proper autorotation airspeed, and then flare at the bottom. There's a concept in helicopter flying known as the "dead person's curve," where too little altitude, too little airspeed, etc., results in insufficient time/altitude to properly enter autorotation and successfully flare and land at the bottom. This incident may end up being a textbook example of that.
 
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Paul V said:
Maybe RRPM got too low
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Looks like it to me also, although it's a bit hard to tell. Those blades seem to be coning upward considerably at the bottom before impact.
 
SoCal 182 Driver said:
My guess is that the pilot was flying low and fast along the coast, and when they had a problem, there wasn't sufficient time to lower the collective, pitch for proper autorotation airspeed, and then flare at the bottom. There's a concept in helicopter flying known as the "dead person's curve," where too little altitude, too much airspeed, etc., results in insufficient time/altitude to properly enter autorotation and successfully flare and land at the bottom. This incident may end up being a textbook example of that.
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The HV chart is only applicable when power is being applied. In this case he was already in a glide and screwed up at the bottom which happens. We do autos in all types of flight profiles to include zero airspeed/OGE and low level.

Here is a video of some colleagues doing low level autos/ engine failure immediately after take off.

 
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k9medic said:
The HV chart is only applicable when power is being applied. In this case he was already in a glide and screwed up at the bottom which happens. We do autos in all types of flight profiles to include zero airspeed/OGE and low level.

Here is a video of some colleagues doing low level autos/ engine failure immediately after take off.

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It take a lot of skill to do that kind of auto. And, of course, he was power on until something quit. I'm guessing he was outside the HV envelope and couldn't recover.
 
SoCal 182 Driver said:
My guess is that the pilot was flying low and fast along the coast, and when they had a problem, there wasn't sufficient time to lower the collective, pitch for proper autorotation airspeed, and then flare at the bottom. There's a concept in helicopter flying known as the "dead person's curve," where too little altitude, too much airspeed, etc., results in insufficient time/altitude to properly enter autorotation and successfully flare and land at the bottom. This incident may end up being a textbook example of that.
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Certainly too much speed wouldn't be an issue, but a blessing.
 
Autorotation is just taking the Potential energy speed and altitude and getting it into the rotor system as Kinetic energy so you can use it at the bottom…low level high speed autos are not a problem…add NVG’s and you can call yourself an Army Aviator…simply a botched auto unless the transmission was locking up as well..
 
Warlock said:
...low level high speed autos are not a problem…add NVG’s and you can call yourself an Army Aviator
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o_O

Or a Naval Aviator or perhaps a Coast Guard Aviator, or maybe a Marine Aviator (crayons or not.) A slim possibility, an Air Force pilot. Perhaps, more than likely an EMS or LEO helicopter pilot. :p
 
k9medic said:
o_O

Or a Naval Aviator or perhaps a Coast Guard Aviator, or maybe a Marine Aviator (crayons or not.) A slim possibility, an Air Force pilot. Perhaps, more than likely an EMS or LEO helicopter pilot. :p
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Don’t forget crop dusters.
 
Piperonca said:
Don’t forget crop dusters.
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One of my close friends, with tens of thousands of helicopter hours, died while crop dusting when his engine failed. Almost no time to get the collective down, flare to bleed-off airspeed, and set it down.
 
SoCal 182 Driver said:
One of my close friends, with tens of thousands of helicopter hours, died while crop dusting when his engine failed. Almost no time to get the collective down, flair to bleed-off airspeed, and set it down.
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Wonder what the correct procedure is. Seems like during high speed nap of the earth you’d bottom the collective and back on the cyclic to trade airspeed for altitude till at auto speed then forward to maintain that speed to the flare/full collective. Is that just dead man’s land?
 
Radar Contact said:
Wonder what the correct procedure is. Seems like during high speed nap of the earth you’d bottom the collective and back on the cyclic to trade airspeed for altitude till at auto speed then forward to maintain that speed to the flare/full collective. Is that just dead man’s land?
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Very hard to do when you're at a low altitude. Things happen really fast when you lose an engine at that speed, and that altitude.
 
SoCal 182 Driver said:
One of my close friends, with tens of thousands of helicopter hours, died while crop dusting when his engine failed. Almost no time to get the collective down, flare to bleed-off airspeed, and set it down.
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Same thing happened to a home town fellow I knew. That's why I mentioned it. Hard way to make a living. Or try to.
 
IK04 said:
That was a completely botched autorotation.
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Agreed. What do you see happening there? Panicked and forgot to put the collective down until late in the game? Other?
 
SoCal 182 Driver said:
Very hard to do when you're at a low altitude. Things happen really fast when you lose an engine at that speed, and that altitude.
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Refer to the video I posted.

Trade airspeed for rotor RPM and flare.


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He’s cruising down the beach with passengers. Probably didn’t even realize he lost power for awhile. I would imagine it doesn’t take long for things to get bad when you’re that low. I know the 44 has much better rotor inertia than the 22, but when I took a few lessons in the 22, they told me you had 6 seconds to lower the collective before rpm’s would be unrecoverable. The pilot might have just not been paying close enough attention.
 
Radar Contact said:
Wonder what the correct procedure is. Seems like during high speed nap of the earth you’d bottom the collective and back on the cyclic to trade airspeed for altitude till at auto speed then forward to maintain that speed to the flare/full collective. Is that just dead man’s land?
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pretty much. Full down collective to maintain rpm. Adjust collective as needed. Flare to trade off whatever airspeed you have to arrest the descent, forward cyclic and pull. Not much difference from an autorotation at altitude other than the fact that when you’re down low you can’t really do much to change your airspeed. Not enough time.

that’s all textbook / practice when you’re expecting it. The R44 is pretty forgiving and has enough inertia to give the pilot a little more time to react than say an R22 but at low altitude…. Those few seconds really matter.
 
SoCal 182 Driver said:
Have you ever done an autorotation in a true engine-out emergency?
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Yes. Three (in three different types of single engine helicopters) of them to the ground. One was at night. That landing left skid marks on the road where I landed and also in some clothing. I have also done thousands of them as an instructor which is what saved my butt when the reals ones happened.



Salty said:
He’s cruising down the beach with passengers. Probably didn’t even realize he lost power for awhile. \
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Trust me. Based upon my personal experiences, he noticed immediately.
 
Radar Contact said:
Wonder what the correct procedure is. Seems like during high speed nap of the earth you’d bottom the collective and back on the cyclic to trade airspeed for altitude till at auto speed then forward to maintain that speed to the flare/full collective. Is that just dead man’s land?
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At the speeds and altitudes we spray if the engine quits it will not be much of an auto. Not enough time to do anything when the thing breaks at five feet.
 
Radar Contact said:
Wonder what the correct procedure is. Seems like during high speed nap of the earth you’d bottom the collective and back on the cyclic to trade airspeed for altitude till at auto speed then forward to maintain that speed to the flare/full collective. Is that just dead man’s land?
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Some helicopters have an avoidance curve in that area as well. Generally it starts around 20ft or less and above 50-60 kts. It’s an area that in the event of engine failure, the late reaction time the aircraft can settle. To arrest the settle will require a good decel, possibly striking the tail.
 
k9medic said:
Yes. Three (in three different types of single engine helicopters) of them to the ground. One was at night. That landing left skid marks on the road where I landed and also in some clothing. I have also done thousands of them as an instructor which is what saved my butt when the reals ones happened.
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Good. So you'll agree, there are human factors involved, especially when the engine quits suddenly (unlike the thousands you've done as an instructor, where the throttle gets chopped but power remains). The video you posted was no doubt thought out and planned. Having an engine quit without warning, especially at low level, is a entirely different situation. This scene from "Sully" sums it up perfectly.

 
Not a lot of time to do much of anything from this altitude other that a quick “awe f**k”
 

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I'm not sure where you are trying to go here... There are always human factors involved. There is also the "oh crap" factor that goes with it. Maybe I'm missing something.

In a helicopter when you chop the throttle there is no power to the rotor. It doesn't matter how the power stops getting to the rotor, the fact remains that it no longer is being powered.
 
I don't know anything about flying helicopters, but it appears this pilot did a pretty good job avoiding swimmers while remaining close enough to shore to facilitate rescue efforts by the locals. I guess he could have set down further from shore but it did not appear he had the ability to do that. Of course that could have caused all three to drown waiting for rescuers. IDK :dunno:
 
k9medic said:
I'm not sure where you are trying to go here... There are always human factors involved. There is also the "oh crap" factor that goes with it. Maybe I'm missing something.
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The point you’re missing is that the video you posted shows a planned autorotation with a planned throttle chop. Much, much different than a real world engine failure at low altitude, with the natural/normal human factors, much like the difference between the NTSB simulations compared to the real world reactions, as depicted in the clip from “Sully.”
 
SoCal 182 Driver said:
The point you’re missing is that the video you posted shows a planned autorotation with a planned throttle chop. Much, much different than a real world engine failure at low altitude, with the natural/normal human factors, much like the difference between the NTSB simulations compared to the real world reactions, as depicted in the clip from “Sully.”
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In post #6 you said your guess was that "there wasn't sufficient time to lower the collective, pitch for proper autorotation airspeed, and then flare at the bottom."

There was in fact enough time. The video was just an example that showed you can train for and successfully execute a low level auto rotation. This pilot had plenty of time but screwed up with little to no flare. This type of screwup has happened before and will happen again.

For the record, at the training level the video depicts, most of the time the only person who knows when the "emergency" will occur is the instructor. Correlation level learning...
 
k9medic said:
In post #6 you said your guess was that "there wasn't sufficient time to lower the collective, pitch for proper autorotation airspeed, and then flare at the bottom."

There was in fact enough time. The video was just an example that showed you can train for and successfully execute a low level auto rotation. This pilot had plenty of time but screwed up with little to no flare. This type of screwup has happened before and will happen again.

For the record, at the training level the video depicts, most of the time the only person who knows when the "emergency" will occur is the instructor. Correlation level learning...
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Implied in my quote in post six were the human factors. Your video shows a training environment, which can be different than a real world engine-out in a helicopter at low level and high speed. Don't you think Sullenberger trained for hundreds of hours on handling engine failure(s)? Of course he did, but when it came time for the "real deal," human factors played a part in the plane landing in the river rather than on dry land (as discussed in the clip from the film I posted). You can't discount that when examining what happened in this crash. Bottom line -- yes, it's likely the NTSB will attribute this to pilot error (unless a mechanical anomaly is discovered), but you can't simply say the PIC "screwed the pooch" without including in the analysis the human factors that were part of the equation.
 
Fair enough.

I will assert that the human factor that most played a part in this event was the decision the pilot made to not flare at the appropriate time which lead to the unsuccessful arresting of the rapid rate of descent during an engine failure. My assertion is qualified based upon both my professional experience as an instructor pilot and from my own personal experiences with three engine failures in helicopters.
 
k9medic said:
My assertion is qualified based upon both my professional experience as an instructor pilot and from my own personal experiences with three engine failures in helicopters.
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This calls into question the crash PIC's experience. If he was a low-time pilot with just his private, comparing him to your experience probably isn't a fair comparison. It will be interesting to see what his total hours in helicopters were at the time of the crash.
 
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