PHI Rooftop Crash

[HeliNomad]

Video is out: http://m.koat.com/news/surveillance-video-shows-unmh-chopper-crash/25659860?utm_campaign=koat&utm_medium=facebook&utm_source=hootsuite

[Flying Pig]

So any ideas? Im not an AStar driver. Pedal locks left in or anything? Last I read the pilot made a comment that the pedals felt locked (I think I read that)

[HeliNomad]

Assuming this was a stuck left pedal, based on my training in the EC-130 I would continue a climb to get away from the building, spiral up, then once I had enough altitude, lower collective which removes the torque and transition to forward flight. Above 40 knots the tail would keep you in control...then execute a stuck left pedal run on landing EP. If this happened in an area with flat ground like an airport environment I might have tried a hover auto...but there is no stable hover with a stuck pedal. This guy is lucky to be alive.

 

I think there a second lesson here which is to always pull into a stabilized hover...if this was a stuck pedal from the ground I think he would noticed as soon as he got light on the skids.

[Velocity173]

Of the course the other video on that website, the news people are trying to make this into a safety record issue with PHI. When you have as many helicopters as PHI, you're gonna have accidents. That's not a trend, it's just statistics.

 

As far as the accident, once the tail went past 90 degrees with full right pedal, I think I would have been dropping the collective. Only reason I could see it getting that high is if the was some sort of HYD failure and he couldn't get the collective down. At any rate, no serious injuries, he never let it leave the roof of the building...a okay.

[Flying Pig]

On another note...... all the spray nozzles are shooting inwards on to an empty pad with the helicopter burning outside the perimeter. Might be something to look at. Did the designers just assume a helicopter would crash ON the pad?

[Francis Meyrick]

 

 

Of the course the other video on that website, the news people are trying to make this into a safety record issue with PHI. When you have as many helicopters as PHI, you're gonna have accidents. That's not a trend, it's just statistics.

A lot of us believe wholeheartedly and implicitly that "zero accidents is possible". 2013 proved that. It takes "fight", and a certain mindset, and never, ever, giving up on that target.

This one... (shakes head).... wait until the accident is fully investigated and reported on. Patience. There are just a bunch of trees that are going to succumb to this one. There will be paper enough to cover every last rivet on this machine a thousand times over. Truth will out, eventually.

[Whistlerpilot]

Coincedentally I just did my AS350 training with my new employer a month ago. While we were practising stuck pedals in the hover I commented that it's all great doing the procedure when you're expecting it and have thought about the emergency procedure but it would be hard to do less than a full rotation if you were caught off guard. My training pilot said well lets try it, so we did a full spin before I lowered collective which meant another full spin on the ground. It was great training and reinforced to get that collective down fast if a spin starts in a hover. Darn Astar without a twist throttle on the collective!

 

They got out alive on this one, but like all accidents we can learn. Reinforces for me to have the muscle memory filed in the brain for a stuck left pedal AS350 (spin) IGE hover. There just is not time to rationalize and think it through as it happens. To the pilots credit he/she kept it over the building and got it down. Different outcome than the recent Seattle AS350 roof top spin. Time will tell in both accidents what happened, but my learning moment is get the collective down and spin to a stop if the machine does an uncommanded yaw in the hover.

 

7.1.1 Failure of the Tail Rotor in Hover or at Low Speed
- IGE bring the aircraft to the ground by reducing collective
pitch before the yaw rate is too high.

 

Ooops the yaw rate got "too high" but hey they were walking away from the aircraft in the video so it could've been worse.

 

 

From the AS350 Manual:

 

7 TAIL ROTOR FAILURE
7.1 Tail Rotor Drive Failure
Loss of the tail rotor in power-on flight results in a yaw movement to
the left; the extent of such rotation wi ll depend on the power and
speed configuration at the time the failure occurs .
* If installed
EASA Approved: 350 B2 3.1
06 -21 Page 4
R
FLIGHT MANUAL
7.1.1 Failure of the Tail Rotor in Hover or at Low Speed
- IGE bring the aircraft to the ground by reducing collective
pitch before the yaw rate is too high.
- OGE reduce collective pitch moderately, to reduce yaw torque,
and simultaneously start to increase speed. R
7. 1.2 Failure in Forward Flight
- In forward flight reduce the power as much as possible and maintain
forward speed (weathercock effect), select a suitable landing area
for a steep approach at a power enabling a reasonably coordinated
fl i ght.
- On final approach, shut down the engine and make an autorotative
landing at the lowest possible speed.
7.2 Tail Rotor Control Failure
CAUTION: LANDING IS MADE EA SI ER BY A WINO COMING FROM THE RIGHT. IF THE R
AIRSPEED IS LOWER THAN 20 kt (36 km/ h), GO-AROUND IS IMPOSSIBLE R
DUE TO THE LOSS OF EFFICIENCY OF THE FIN . R
- Set lAS 70 kt (130 km/ h} , in le vel fl ight.
- Press the HYDR TEST (TEST HYDR) push-button (this cuts off hydraulic R
power to the yaw servo-control and depressurizes the load-compensating
servo accumulator). After 5 seconds , reset the test button to the
normal position.
- Make a shallow ap proach to a clear landing area with a slight side
slip to the left. Perform a run-on landing; the side slip will be
reduced progressively as power is applied.

[HeliNomad]

Isn't the aircraft in the video a B3?

[Flying Pig]

Not anymore

[HeliNomad]

Not anymore

LOL

[JDHelicopterPilot]

Yes, it is a B3. It also has the throttle on the collective.

[Whistlerpilot]

Bummer the pilot didn't roll the throttle off and just land. I haven't flown the B3, doesn't the throttle have a lock? Would it be possible to have a hard time getting the throttle off?

[iChris]

Based on my training in the EC-130 I would continue a climb to get away from the building, spiral up, then once I had enough altitude, lower collective which removes the torque and transition to forward flight. Above 40 knots the tail would keep you in control...then execute a stuck left pedal run on landing EP.

 

 

Who taught you that spiral up & flyaway technique? Not a factory school or in the RFM. It’s been around for a long time as an old urban legend type of technique; however, it has never made it into the RFMs.

 

As I remember, it was for a specific helicopter and the technique was found to required skills beyond common levels during flight test. Moreover, if done at the wrong time or incorrectly, the results could be catastrophic over standard procedures.

 

In any emergency, your first action should result in an improvement in your current situation. That technique puts you in a higher hover with an increased yaw rate, your situation has worsened. That technique sounds easy; however, when that yaw rate increases, you can very easily loose control.

 

Tail Rotor Control Failure: HOVER-IGE

 

LAND IMMEDIATELY

 

1. Twist Grip :IDLE STOP POSITION

 

2. Collective INCREASE to cushion touchdown

 

The EC pilot twists the grip to move it out of the "FLT" detent to the "IDLE" setting, the Digital Engine Control Unit then adjusts the engine to the idle rpm.

 

HeliNomad, on 26 Apr 2014 - 09:11, said:

 

I think there a second lesson here which is to always pull into a stabilized hover...if this was a stuck pedal from the ground I think he would noticed as soon as he got light on the skids.

 

That could have kept them on the pad. Some of what we talked about in the Dynamic Rollover Post

 

Always use a two-step liftoff. Pull in just enough collective to be light on the skids and feel for equilibrium, then gently lift the helicopter into the air.

Edited April 27, 2014 by iChris

[HeliNomad]

 

Who taught you that spiral up & flyaway technique? Not a factory school or in the RFM. Its been around for a long time as an old urban legend type of technique; however, it has never made it into the RFMs.

 

As I remember, it was for a specific helicopter and the technique was found to required skills beyond common levels during flight test. Moreover, if done at the wrong time or incorrectly, the results could be catastrophic over standard procedures.

 

In any emergency, your first action should result in an improvement in your current situation. That technique puts you in a higher hover with an increased yaw rate, your situation has worsened. That technique sounds easy; however, when that yaw rate increases, you can very easily loose control.

 

Tail Rotor Control Failure: HOVER-IGE

 

LAND IMMEDIATELY

 

1. Twist Grip :IDLE STOP POSITION

 

2. Collective INCREASE to cushion touchdown

 

The EC pilot twists the grip to move it out of the "FLT" detent to the "IDLE" setting, the Digital Engine Control Unit then adjusts the engine to the idle rpm.

iChris,

 

We are in total agreement here. The technique was taught to me by a very advanced EC-130 and AS350 instructor who has been working with me for a couple years now. It's a technique that we practice just as I pull into a hover into the wind he limits my right pedal to just beyond neutral. This gives you just enough to think you have enough tail rotor authority to pull into the hover but nothing more. You continue up as slow as you need to in order to maintain a constant yaw rate up to the point where a lowering of the collective with a gentle push of the cyclic just as the wind brings the tail around for transition to forward flight. His point of teaching this is exactly for the situation found in the video where a pinnacle style or yacht environment causes you to have a limited chance of being able to execute a safe hover auto from a slight stuck left pedal. This is just another option, albeit a risky one. If I had any amount of flat ground I would switch to idle on the collective and execute a hover auto, something the EC-130 does really well. If anything it's a fun exercise to practice with your other stuck pedal exercises. Now thinking about this my self, had it been me in that helicopter on the building top I hesitate to say with confidence that I would have executed this spiral up technique. It's possible the yaw rate was too great in this instance. Like you reiterated, one more reason for the two step pick up...

[adam32]

Anyone remember the Enstrom (I think) that reported a stuck pedal/TR failure that crashed then cockpit video was released and the pilots feet never once moved on the pedals...just saying maybe there wasn't a mechanical failure on the PHI B3...

[Francis Meyrick]

Monday morning quarter-backing...

 

[Whistlerpilot]

Guilty as charged.

[aeroscout]

Monday morning spectating for me.

[OGE]

I know the video is a step-recording or whatever you call it where it captures fragments and we can't look at all of it but...since the really obvious and extreme yaw appears to be present from pickup, a slow, 2-step pickup would have prevented the outcome.

I'm amazed that they managed that many rotations before the end...maybe skill but also plenty of luck.

[Nearly Retired]

OGE, I agree. It seemed to start turning as soon as the skids broke ground. Had it been me (he says, from the comfort of his easy chair on Monday morning) I "simply" would've put the pitch back down instead of yanking it into the air.

 

Easy to say.

 

I suspect that in addition to the unanticipated yaw, the pilot had *other* issues going on just then that were occupying his time and attention. I have no idea what they were.

 

~Bob

[aeroscout]

You can become disoriented very quickly with a yaw rate after a couple of turns. If it's a high yaw rate, maybe even less. I like the easy lift off the ground. I try to make it almost imperceptible leaving the ground.

[Francis Meyrick]

I think I prefer to make my leaving the ground perceptible. Uh-huh.

 

[aeroscout]

I think I prefer to make my leaving the ground perceptible. Uh-huh.

 

Well, that gives you a wonderful opportunity to make up for it on the other end.

[Francis Meyrick]

Touche... I am slap-ped down...

 

So this morning I find a dubious looking plastic spray bottle in my cockpit. The label says something about a pleasant orange smell. Maybe it's a subliminal message. I don't know.

Putting on my best mock-serious expression, I carry it over to my good buddy, the ground helper/cleaner.

I ask him: "If I find it in the cockpit, can I keep it?"

It is intended as a very, very mild rebuke/wisecrack.

He, (unperturbed) (chewing tobacco), "Do you want it?"

 

Touche.... I am, indeed, slap-ped down.