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Crash kills pilot and Troy Gentry


adam32

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If I read that correctly, he knew he couldn't set it down without crashing, so he sat in a hover waiting for the emergency services to arrive?
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Well if he could hover, then he could also land, even with a stuck throttle or whatever, if the reporting is actually factual, and I have doubts about that, all you have to do is to just get into a stable hover over some flat ground like a runway and do a hovering auto. but since I was not there and I don't know the pilot or the school, I will keep my further opinions to myself.

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Not an uncommon scenario. The pilot attempts to land and finds the throttle stuck. Each attempt to lower collective and landing results in an impending over-speed. He may have felt he needed to wait for some type of fire-rescue unit before attempting his emergency landing.

 

Some pilots have not been trained for this type of mechanical malfunction; therefore, it’s not an uncommon accident outcome from stuck throttle. Though unusual to be a fatal occurrence.

 

NTSB Identification: GAA17CA178

Aircraft: SCHWEIZER 269C

The flight instructor of the helicopter reported that, about halfway through the flight, he “discovered that the throttle control was inoperative” and stuck in the high rpm setting. He turned the helicopter back to the departure airport and briefed his student on the situation. Upon being cleared to land, he executed a “running landing” and performed a go-around on the first try. On the second try, the skids made hard contact with the runway, and the helicopter came to a stop.

Examination revealed that the helicopter had sustained substantial damage to the fuselage. The flight instructor reported that the throttle cable outer housing separated from the inner solid housing at the throttle linkage and that the internal wire could flex outside of the housing.

 

The National Transportation Safety Board determines the probable cause(s) of this accident as follows: The separation of the throttle cable’s outer housing from the inner housing at the throttle linkage while at a high-power setting, which prevented the pilot from being able to control the throttle and execute a proper landing flare and resulted in a hard landing.

 

NTSB Identification: DEN78DTC15

Aircraft: HUGHES 269B

COLLIDED WITH: DIRT BANK

 

PROBABLE CAUSE(S)
PILOT IN COMMAND - ATTEMPTED OPERATION W/KNOWN DEFICIENCIES IN EQUIPMENT

POWERPLANT - ENGINE CONTROLS: THROTTLE-POWER LEVER

THROTTLE STUCK IN OPEN POSITION FOR UNKNOWN REASON

 

NTSB Identification: MIA97LA038

Aircraft: Bell 47G, registration

The pilot stated that as he was descending on right base for landing, the throttle stuck full open, and the engine began to over speed. He entered autorotation and turned into the wind. Reportedly, he did not initiate a deceleration (flare), and the helicopter collided with the ground in a nose-high attitude, bounced, nosed over, and came to rest inverted. The helicopter was destroyed by a postcrash fire. No pre-accident deficiency was found during examination of the wreckage.

 

NTSB Identification: ATL94LA025

Aircraft: SIKORSKY H34-G

THE HELICOPTER WAS CONDUCTING LONG LINE EXTERNAL LOGGING OPERATIONS. THE PILOT STATED THAT HE WAS AT A HOVER, WITHOUT A LOAD, AND THE AIRCRAFT THROTTLE SEIZED AT ABOUT HALF THROTTLE. HE EXECUTED A FORCED LANDING INTO A GROUP OF TREES, AND THE AIRCRAFT RECEIVED SUBSTANTIAL DAMAGE. INSPECTION OF THE THROTTLE AND THROTTLE LINKAGE TO THE ENGINE DID NOT REVEAL ANY MALFUNCTION.

 

NTSB Identification: NYC96LA099

Aircraft: Elves ROTORWAY EXEC 90

The homebuilt, experimental helicopter was on approach to an off-airport landing area, when the pilot realized that he could not change the throttle setting. The helicopter touched down hard, and one skid collapsed. The collective/throttle assembly was removed. When heated, the throttle became difficult to move. Testing by the kit manufacturer obtained similar results. The bushings that restricted the throttle movement were supplied by the kit manufacturer.

 

TH-55 9-14. Throttle Failure

If the throttle becomes inoperative in flight, continue to a landing area that will permit a shallow approach and running landing. As descent is begun, make collective pitch adjustments smoothly and minimize the amount of movement to aid in maintaining rpm within limits.

 

If descent cannot be made without an excessively high rpm, fly to a suitable area and accomplish an autorotational landing. In this situation, the mixture control must be moved to the lean position before the collective pitch is lowered to enter autorotation. If the throttle fails at a hover, lower the collective (disregarding engine rpm) and land. After the helicopter is on the ground, move the mixture control to the lean position.

Edited by iChris
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How about turning off one of the mags and doing a shallow approach to a run on landing with the engine down on power?

That's not a good idea. Don't deliberately compromise the efficiency of your engine.

 

A shallow approach is used when you are power limited; in this instance you are experiencing the opposite. A high collective pitch setting must be maintained to prevent an engine and rotor over speed.

 

Execute a steep approach (which requires a higher pitch setting) to a hover. Once in the hover, instruct passenger to pull the fuel control and execute a hover auto.

 

If it is not possible to perform a steep approach without over speeding, set up for an autorotation at altitude to a runway. Instruct passenger to pull fuel control; execute a full down auto with engine off.

 

If you do not have access to a runway or a very forgiving area to autorotate; execute a steep approach and accept the fact that you will have an overspeed. Once the overspeed occurs, minimize hover time and ground the aircraft.

Edited by Hand_Grenade_Pilot
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And to clarify, what I described above is in response to a wide open throttle scenario.

 

A stuck throttle at a low power setting would require a run on landing. In the event that there is not a suitable landing site for a run-on, you would have to execute an autorotation with the engine on, and use what power is available to assist at the end of the auto.

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So you're stitting there in a hover with the throttle wide open?

What will happen if you just lower the collective all the way?

You'll experience a massive engine and rotor overspeed as you're setting down.

 

To elaborate even further... with the throttle stuck in the full open position, you will not be able to complete a power on approach without over speeding. If it's stuck at a high power setting (perhaps 80% or so) in theory you could perform a high power approach (very slow rate of closure, very low rate of descent) to a hover. Then cut fuel to the engine and hover auto. It's also largely dependent on DA, aircraft weight and wind. Low weight, low DA and high wind speed would make it more difficult to perform the approach without overspeeding.

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What I meant was, will the engine say, blow like an overreved race car, start a fire, or something?

 

,...'cause to be honest, if my throttle was stuck the last thing I would care about is sparing the aircraft! If all I'm gonna get is the needles pegged at the top for a minute while I reach for the mixture (after landing) so what?,...f**k the engine!

 

I hope they can figure out what really happened, because this one is just too strange,...and disturbing!

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What I meant was, will the engine say, blow like an overreved race car, start a fire, or something?

,...'cause to be honest, if my throttle was stuck the last thing I would care about is sparing the aircraft! If all I'm gonna get is the needles pegged at the top for a minute while I reach for the mixture (after landing) so what?,...f*ck the engine!

I hope they can figure out what really happened, because this one is just too strange,...and disturbing!

In the brief time it would take to land while over speeding, no, I would not expect a catastrophic failure from the engine or drive train.

 

That being said, for a professional pilot, performing a successful full down autorotation to a runway should not be difficult task. Unlike an unexpected engine failure, you get to decide when to initiate, and have the luxury of being able to miss your mark by thousands of feet. All you have to worry about is maintaining stable glide and a nice flare. I would elect to perform an autorotation to preserve the engine, transmission, drive shafts etc as that is a maneuver I am comfortable performing.

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I don't know, in a Jet Ranger (that glides like,...forever) yeah, maybe? A 269 however, that makes a 22's glide look long!

 

I guess if you must, decend to a hover, shut the fuel valve off, then wait for the hover auto?

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I don't know, in a Jet Ranger (that glides like,...forever) yeah, maybe? A 269 however, that makes a 22's glide look long!

I guess if you must, decend to a hover, shut the fuel valve off, then wait for the hover auto?

The length of the glide is irrelevant in this scenario. You're not trying to make a specific spot; anywhere on the runway will suffice. No need to do anything fancy to adjust the glide path.

 

And getting it to a stable hover with a fixed throttle setting (without overspeeding) is a long shot to say the least. More then likely, you will be performing an autorotation from altitude (if the pilot is comfortable doing so).

 

If the pilot has any doubt that the autorotation could be performed safely, then they should perform a power on approach, land immediately and have the necessary overspeed inspections done.

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And while the H269 (or Schweitzer 300 if you'd prefer) does drop like a brick in an autorotation (as do all helicopters with more than two blades) I found it to be much easier to manage then the R22. The rotor system has a little more inertia, making RPM fluctuations less dramatic. The landing gear is also more robust and can handle harder ground contact.

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And getting it to a stable hover with a fixed throttle setting (without overspeeding) is a long shot to say the least. More then likely, you will be performing an autorotation from altitude (if the pilot is comfortable doing so).

 

Well in that case, I'm back to my original plan, f*ck the aircraft, let it overspeed!
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