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Whimlew 8th Sep 2017 18:14

Helicopter crashes at Lumberton airport
 
Helicopter crashes at Lumberton airport

Helicopter crash at Burlington County airport
http://philadelphia.cbslocal.com/201...icopter-crash/

Airbubba 8th Sep 2017 21:21

According to archived radio traffic from Burlington County Fire and EMS, the helicopter was in a hover with a mechanical problem waiting for the fire department to arrive. They attempted a landing, ended up in flames. One occupant was declared dead at the hospital, the other at the scene.

From one of the links posted above:


Troy Gentry killed in Lumberton helicopter crash

Courier-Post Published 1:21 p.m. ET Sept. 8, 2017 | Updated 4:10 p.m. ET Sept. 8, 2017

LUMBERTON - One half of a popular country music duo was killed in a helicopter crash here this afternoon.

Troy Gentry, of the band Montgomery Gentry, died when the helicopter he was in crashed at the Flying W Airport, the band confirmed through social media Friday afternoon.

The aircraft went down around 12:37 p.m. Friday. The band had been set to perform this evening at the airport, which also houses a resort.
Another man was killed in the crash, officials said. His identity has not yet been released.

One victim died at the scene and the second man had to be extricated from the wreckage. He was taken to Virtua Marlton Hospital, where he later died, according to a spokesman for the Burlington County Prosecutor's Office.
From the NTSB's Twitter feed:


NTSB is investigating today’s accident in Lumberton, NJ involving a Schweitzer [sic] H269.
An outfit called Helicopter Flight Services at Flying W Airport advertises:


Become a Helicopter Pilot in one of Our Schweizer Helicopters and enjoy beautiful views like this.

Get directions to the Flying W and come and visit our hanger [sic] and facilities, both at the school and at the Airport.
Medford, New Jersey Helicopter Flight Services - Helicopter Flight Training, Helicopter Sight Seeing Tours, Aerial Photography

givdrvr 10th Sep 2017 13:29

Below is a link to the EMS audio confirming that the helicopter was still hovering on the airport grounds when they arrived.

https://theblast.com/troy-gentry-hel...ergency-audio/

Old Farang 11th Sep 2017 03:19

Hmm, many years ago during my ab initio training in a H 300 with an instructor, one of the skid oleos let go, I guess it may have been both, on one side, allowing the skid to swing down. Long time ago now but I do remember getting out of the thing and holding the skid back in position while the instructor landed the machine. Should of turned me off of helicopters right then I suppose, but didn't.

R.I.P. to the victims.

cncpc 11th Sep 2017 05:08

What Could this be...Gentry Helicopter Accident in US
 
A pilot and passenger, a fairly well known member of a country music duo, Montgomery Gentry are killed in the crash of a Hughes 300 or Schweizer 300. The odd thing is that they declared an emergency with some kind of malfunction and said they were hovering awaiting the arrival of emergency services. Emergency services did arrive just as the machine went down off the end of a runway in the eastern US.

Looking for comments on what kind of malfunction would it have been where the landing was so much worse than hovering that a pilot would choose to wait for emergency crews in a hover.

It seems that eventually it went in right side up, flipped over, and that was it. It looks like there is no rotational damage on the main rotor blades.

Story here, other video on YouTube.

chad_blakey3 11th Sep 2017 05:38

the throttle was hung wide open.he knew he was going to have to put it down and he wanted to wait for the emergency team to get there in case there where injury's

[email protected] 11th Sep 2017 12:14

Why not just shutdown the engine?

Thomas coupling 11th Sep 2017 12:42

Pprune time.....

I'm guessing one of the oleo's / skids broke and he couldn't do a level landing.
Either he ran out of fuel or tried to land upright but failed. Cab rolled, blades hit and - game over.

Several options available:

Land with duff skid up slope and shut throtors down slowly.
Use sandbags under the duff skids.
Attempt to fix duff skids whilst in the hover.
Extricate any surplus crew to minimise injured parties, prior to landing.

What else could have gone wrong - yet gave the pilot time to hover and wait for assistance?

Sad.

RiP.

[email protected] 11th Sep 2017 14:47

Yes, plenty of options for an undercarriage failure but I was responding to chad's assertion that it was just a stuck throttle:ok:

Thomas coupling 11th Sep 2017 15:16

Copied that.

Presumably then the throttle was wide open and the pilot couldn't shut it down?
What about the fuel shut off valve?
What about an engineer climbing aboard and shutting it down at the engine?
What about waiting to run out of fuel.

cncpc 11th Sep 2017 15:45

Two blades can be seen. They don't seem to have come in contact with anything at the leading edge. One is fractured upwards near the hub, likely from rollover.

It seems he was able to hover, but not move forward. And then, couldn't hover. Does stuck throttle affect the up down on the collective? Through the correlator?

nigelh 11th Sep 2017 16:09

I would have thought that all the controls ( aerodynamic ) must have been working in order to hover . I guess that if duals were fitted it would be difficult to get the pax out without interfering with them ...if not he could have just let the pax out before trying to land ? Very strange and a tragic end . As TC has said many people have landed with broken undercarriage / wheels etc by landing on tyres but it appears this was not mentioned and how would they know there was an oleo problem ( if there was one ?) ....i am not sure of any change in the behaviour even if they were faulty .
( I have had G R in one many years ago but that needs contact with the ground ) Baffling ....
Lastly if the throttle was stuck how would they know ? Maybe on approach , but that would mean overspeed and you would then set up for a long and low approach i guess ? Once in the hover just do an engine shut down by pulling the fuel ...that HAS to work and in a 1ft hover you would just need to keep it straight with pedals .... It HAS to be something else ...

cncpc 11th Sep 2017 21:42

Now a report a couple of hours ago saying the information conveyed by the pilot was that he was having difficulty controlling RPM, and that he had initiated an autorotation that was short of the runway, which ended up as it did.

I take it that means he was having difficulty with RMP surging, or keeping the rotor in the green. Yet he could hover.

Possible developing seizure of the main transmission. My training was that if the transmission was seizing, not to roll the power off for the auto. If you do, the blades stop.

Troy Gentry's Fatal Helicopter Ride Was 'Impromptu'

Airbubba 13th Sep 2017 18:26

Preliminary report from the NTSB:


NTSB Identification: ERA17FA317
14 CFR Part 91: General Aviation
Accident occurred Friday, September 08, 2017 in Medford, NJ
Aircraft: SCHWEIZER 269C, registration: N204HF
Injuries: 2 Fatal.

This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed. NTSB investigators either traveled in support of this investigation or conducted a significant amount of investigative work without any travel, and used data obtained from various sources to prepare this aircraft accident report.

On September 8, 2017, about 1300 eastern daylight time, a Schweizer 269C-1 helicopter, N204HF, operated by Helicopter Flight Services, was substantially damaged during collision with terrain while performing a forced landing to Runway 01 at Flying W Airport (N14), Medford, New Jersey. The commercial pilot and passenger were fatally injured. Visual meteorological conditions prevailed, and no flight plan was filed for the personal flight which was conducted under the provisions of 14 Code of Federal Regulations Part 91.

According to the chief flight instructor for the operator, the purpose of the flight was to provide an orientation/pleasure flight to the passenger who was scheduled to perform in a concert on the airport later that evening.

Several minutes after takeoff, the pilot reported over the airport UNICOM frequency that he was unable to control engine rpm with throttle inputs. He reported he could "roll" the twist-grip, but that there was no corresponding change in engine rpm when he did so.

The company flight instructor and another certificated helicopter flight instructor were monitoring the frequency and engaged the pilot in conversation about potential courses of action to affect the subsequent landing. Options discussed included a shallow approach to a run-on landing, or a power-off, autorotational descent to landing. The pilot elected to stop the engine and perform an autorotation, which was a familiar procedure he had performed numerous times in the past. Prior to entering the autorotation, the pilot was advised to initiate the maneuver over the runway.

The company flight instructor reported that the helicopter entered the autorotation about 950 ft above ground level, and that the helicopter was quiet during its descent "because the engine was off." During the descent, the rotor rpm decayed to the point where the instructor could see the individual rotor blades. The helicopter descended from view prior to reaching the runway threshold and the sounds of impact were heard. Both instructors reported that a high-pitched "whine" could be heard from the helicopter during the latter portion of the descent.

A video forwarded by local police showed the helicopter south of the runway as it entered what appeared to be a descent profile consistent with an autorotation. Toward the end of the video, the descent profile became more vertical and the rate of descent increased before the helicopter descended out of view. No sound could be heard from the helicopter.

The pilot held commercial and instructor pilot certificates, each with ratings for rotorcraft-helicopter and instrument helicopter. His most recent Federal Aviation Administration (FAA) second-class medical certificate was issued April 12, 2017.

Excerpts of the pilot's logbook revealed he had logged 480.9 total hours of flight experience. It was estimated that he had accrued over 300 total hours of flight experience in the accident helicopter make and model. The last entry logged was for 1.2 hours in the accident helicopter on the day of the accident.

The company training records indicated the pilot had received the training required by the operator for employment as a flight instructor, and his last airman competency check was completed satisfactorily on April 19, 2017 in the accident helicopter.

According to FAA records, the helicopter was manufactured in 2000 and had accrued approximately 7,900 total aircraft hours. Its most recent 100-hour inspection was completed August 17, 2017 at 7,884 total aircraft hours.

At 1254, the weather recorded at South Jersey Regional Airport (VAY), 2 miles west of N14, included clear skies and wind from 260° at 13 knots gusting to 18 knots. The temperature was 21°C, and the dew point was 9°C. The altimeter setting was 30.13 inches of mercury. Airmen's Meteorological Information (AIRMET) Sierra for instrument meteorological conditions and mountain obscurations was in effect for the area surrounding the accident site at the time of the accident.

The wreckage was examined at the accident site, and all major components were accounted for at the scene. The initial ground scar was about 10 ft prior to the main wreckage, which was about 220 ft prior to the threshold of runway 01 and aligned with the runway.

The cockpit was significantly deformed by impact damage, and the tailboom was separated at the fuselage. The engine and main transmission remained mounted in the airframe, and all main rotor blades were secured in their respective grips, which remained attached to the main rotor head and mast. The pitch-change link for the yellow rotor blade was fractured, with fracture signatures consistent with overstress. Each of the three blades was bent significantly at its respective blade root. The blades showed little to no damage along their respective spans toward the blade tips, which was consistent with low rotor rpm at ground contact.

Flight control continuity was established from the individual flight controls, through breaks, to the main rotor head and tail rotor. Drivetrain continuity was also established to the main and tail rotors.

The engine was rotated by hand at the cooling fan, and continuity was confirmed from the powertrain through the valvetrain, to the accessory section. Compression was confirmed on all cylinders using the thumb method. The magnetos were removed, actuated with a drill, and spark was produced at all terminal leads. Borescope examination of each cylinder revealed signatures consistent with normal wear, with no anomalies noted.

The carburetor was separated from the engine, displayed impact damage, and was found near the initial ground scar. The throttle and mixture arms were actuated by hand and moved smoothly through their respective ranges. The filter screen was removed, and was absent of debris. The carburetor contained fuel which appeared absent of water and debris.

The collective control and jackshaft assembly as well as the associated throttle cable, push-pull tube, and bellcrank assemblies were retained for further examination at the NTSB Materials Laboratory.
https://www.ntsb.gov/_layouts/ntsb.a...08X43517&key=1

[email protected] 14th Sep 2017 07:23

So, either the aircraft wasn't rigged properly for autorotation or he let the Nr decay horribly - perhaps he was dropping short and tried to stretch the glide. Very sad.

nigelh 14th Sep 2017 13:25

I must be missing something here .....if you had worries about the throttle you would definitely not sit in a hover waiting . I also see no reason to do an auto . Surely a fairly fast approach and then bleed speed off for a run on would be the simplest as if the engine quit at any time you could continue your flare and auto the last bit . I personally would never shut down a running engine unless i absolutely had to .

Thomas coupling 14th Sep 2017 13:40

*Conjecture warning*

IF the throttle is jammed open, presumably in a piston engine helo the Nr is now dangerously high in an attempt to stay S and L - yes?
So he flies slow or hovers to soak up the Nr, or switches the engine off - yes?

It seems there was a discussion along these lines with ATC/FI.

So he apparently opts for an EOL (not an auto as some state - an auto would drive the Nr off the clock and damage the blades - because he can't control revs). So he enters an EOL state and revs are now totally under his control.

Whatever happened next - 2/3rds of the way down the descent is anyone's guess, but like CRAB says - he must have reduced the Nr below that which is recoverable and the rest is history.

chopjock 14th Sep 2017 14:11

nigelh

I must be missing something here .....if you had worries about the throttle you would definitely not sit in a hover waiting . I also see no reason to do an auto . Surely a fairly fast approach and then bleed speed off for a run on would be the simplest as if the engine quit at any time you could continue your flare and auto the last bit . I personally would never shut down a running engine unless i absolutely had to .
I had a throttle stuck fully wide open in the cruise on an Enstrom, I decided I did not want to blow my engine up as rpms would increase every time I reduced pitch for an approach, so I chose to pull the fuel shut off valve and auto her down.

212man 14th Sep 2017 14:41


So he apparently opts for an EOL (not an auto as some state - an auto would drive the Nr off the clock and damage the blades - because he can't control revs). So he enters an EOL state and revs are now totally under his control
Since when did an 'auto' require the engine to be running? Just because that is the case for training doesn't mean that there is a difference between saying EOL and an Autorotation

nigelh 14th Sep 2017 23:08

I agree about throttle full open ...get into perfect place for autorotation and shut down engine is probably safer than risking overspeeding NR .
An autorotation is exactly the same with or without engine TC and don't try and say otherwise ! There is no connect between engine and drive . I think you are confusing EOL which is specifically referring to the bit at the bottom when you hit terra firma and autorotation which is purely the function of the relative airspeed driving the blades . ( you are so keen to pick us all up on not knowing the difference between VRS , IVRS,
LTE & LTA etc I thought you would appreciate being corrected!!)
The big difference without an engine is in your head when you know you have no room for error at the bottom !!

Hughes500 15th Sep 2017 06:47

Nigel

Will have to disagree here. I have had one engine stop while doing an EOL for a PC in a 300 as it happens ( customers aircraft ). Throttle was rolled back into detent and engine stopped. I can assure you that the ac descended considerably quicker than a normal auto followed by EOL. Having done thousands of EOL's to the ground I speak with total assurance. Quite why, that is is interesting, as you say there is a freewheel disconnect !

[email protected] 15th Sep 2017 07:42

But there will be drag through that freewheel and it is much less with the engine running that with it completely stopped - it might say freewheel on the box but it is not frictionless.

It also depends on where in the transmission chain the freewheel is.

nigelh 15th Sep 2017 07:57

Good point . I have done both and don't think the difference is that much ...but there will be a little less friction maybe if engine is still in idle I agree . It doesn't change the point about EOL and Autos .
Out of interest what would happen if you slowly pulled the fuel shut off ?
Could it reduce fuel flow so you could keep engine on during auto and maybe gain some benefit .... or does it just stop the fuel instantly?

Nubian 15th Sep 2017 08:02


Originally Posted by Hughes500 (Post 9892264)
I can assure you that the ac descended considerably quicker than a normal auto followed by EOL.

The 300 drops like a rock in any case, so are you sure it is actually possible? :eek::E

Thomas coupling 15th Sep 2017 08:31

Nihelh - there you go again egg on face in public talking rubbish, transmitting and then thinking about it afterwards.

You'll never learn will you (well not in all the years you persistently continue to make these silly naiive remarks on a public forum).
Each to their own I guess.

Now back to fact:
As Hughes 500 quite rightly said (you know - the guy who flies the same a/c as yours?).
If you committ to an EOL at the top of the slope, you physically switch the engine off. In an Auto - you don't.
The next few seconds dictate your initial descent speed because one rotor wants to stop as fast as possible on you (EOL) and the other doesn't because of the residual engine drive thru the box (Auto). For heavy helos this RoD is markedly different.
Now this concept might be a little difficult for you to grip: The safe operating range of the rotor during an EOL descent is narrower than that of the Auto because you have the engine acting as a goalkeeper if you droop the Nr too low (some a/c monitor the Nr at this low range and arrest it automatically), so an ab initio or someone who has not rehearsed EOL's much lately, will 'tend' to rely on this safety net whilst manouvering with Nr (for a PFL for instance). With an EOL, the a/c will sink faster - because you haven't got that permanent safety net propping up the low end of your Nr band.
[In an EOL, if you DO go too low in the Nr department - you have no choice but to flare the a/c a little to recover it, but this option is of course limited for obvious reasons).
At the bottom of course, Nr is your best friend and in an EOL situation - your only friend!
Unlike an auto recovery - where you have lots of friends sitting in the engine compartment waiting to come to the rescue if you cock up.

So, sadly Nigel - you're quite wrong and Hughes500 and many other technically aware pilots are too.

As I am - after approximately 2500+ EOL's (and god only knows how many auto's)to date with only one minor incident where I cracked the bottom of the fenestron during a rather enthusiastic flare prior to the level.

And then you further dig a big hole by asking everyone what will happen if you pull the fuel shut off back slowly?
Are you sure now, that you have done several EOL's and auto's because if that was the case, you would be perfectly aware what would happen because you would have either been shown it or tried it yourself (knowing you).
Never mind - I'll just have to explain this to you, also:
Odds are - the fuel shut off is electric upon which once the lever leaves the ON detent, the motor will activate and close the HP valve ASAP probably even before you complete the motion all the way back to OFF.
If the valve is 'steam driven' then the engine will gradually be deprived of fuel and the Nr will decay quickly or slowly dependent on your collective lever position.
Sadly in the case of this tragic accident, it 'appears' the the fuel management system had asked for full fuel supply (I don't know the engine set up in this helo).
Maybe - just maybe, the pilot/ATC/FI agreed the best option was to shut the engine down using the HP valve and adopt an EOL profile.
It was during this phase, something got out of hand and the helo was seen to rapidly increase its RoD and plummet vertically to the ground.

My take (for what it's worth): He dipped below the minimum Nr band and couldn't recover it.

RiP.

Next Gaff please Nigel?:rolleyes:

Hughes500 15th Sep 2017 09:04

I agree with the friction part but wasn't expecting an increased ROD of about 300 ft a min or 15% mind you only done 2 in anger of about 5000 so mind wasn't really on the rpm's !
Nubian, they don't drop like a brick in a normal auto with engine running but at idle they come down at 1800ft per min hardly like a brick, if you want some real excitement ask Crab to do one in a Scout, that will be more like 3000 ft a minute
Pulling the fuel shut off valve would just shut it off instantaneously as you are pulling a lever. could try the mixture but initially the rpm would go up as you wind it out then would slowly starve the engine of fuel.

nigelh 15th Sep 2017 09:32

TC . You are full of it old boy and getting confused in your old age !!
1) EOL does not refer to ,if or if not , the auto is done with or without the engine . It is specifically the LANDING . You can do an auto with engine then elect to shut down to do your EOL . This is the preference of most of my instructors over the years .. ( secret is in the word LANDING ) .
2). It appears even you are not sure what type of fuel shut off is used either ? But you do acknowledge that it could reduce fuel flow and then Nr . So my question was would it be possible , with the old valve , to reduce flow to stop over speed .
Your rampant ego and aggressive nature may frighten some people off from asking questions , which is not helpful !! This is not your show and it shouldn't be used as the TC soap box telling us what a God you ( used ) to be ...... !!!
Ps ... it was rather pleasant and good humoured while you were away . Your not going on holiday again soon by any chance ??!!

jellycopter 15th Sep 2017 10:14

TC said 'Odds are - the fuel shut off is electric upon which once the lever leaves the ON detent, the motor will activate and close the HP valve ASAP'. I have to question whether TC has ever seen a HU269? It's one of the most rudimentary helicopters out there, and it certainly doesn't have an electric fuel cock! It's a simple cable operated device (tap/faucet) via the instrument panel and yes, there could be varying degrees of off or on. So fuel flow could be adjusted by careful adjustment of the fuel shut off control. However, I suspect that being a piston engine, it would quickly mess up the mixture and stop the engine anyway. If it was a turbine, like the HU369, then, in theory at least, the rpm could be controlled with the fuel shut off valve. Not such a stupid question after all Nige.

chopjock 15th Sep 2017 10:42

I had a partially blocked fuel filter on my H369 and the fuel flow was restricted, only allowing 50% torque, just enough to sustain straight and level at 40 kts. So I should imagine careful manipulation of the manual shut off fuel valve might work in an emergency situation...

nigelh 15th Sep 2017 11:41

Phew...!! Maybe not so much egg on my face after all . I am not sure I would want try this without testing the theory on the ground pulling some pitch and see if a gentle pull back would reduce torque. Well , at least I now have some support from two pilots ....... and vitriol from one old ex pilot !!!!
Happy with that 😎👍

Ps . Before another attack ... I am not advocating this approach to stuck ( high) throttle . Just wondering if it may work in some cases where the shut off is a manual valve ?

Reely340 15th Sep 2017 14:02


Originally Posted by Hughes500 (Post 9892264)
Nigel

Will have to disagree here. I have had one engine stop while doing an EOL for a PC in a 300 as it happens ( customers aircraft ). Throttle was rolled back into detent and engine stopped. I can assure you that the ac descended considerably quicker than a normal auto followed by EOL. Having done thousands of EOL's to the ground I speak with total assurance. Quite why, that is is interesting, as you say there is a freewheel disconnect !

I need some clarification here.:O

An "auto" is what? Engine running at healtly rpms followed by pitch down?
W/o reducing throttle to "high idle" it will be hard to demonstrate power off green arc control by pitching, as slightly raising the pitch (in a 300) will remove the needle split due to the throttle correlator.

An "EOL" is an Engne Off Landing. Off as in 0 rpms? If yes, I think almost nobody has down that deliberately.
Is an EOL what I described as "auto" above? Being aerodynamically in auto rotation with noticeable needle split due to engine idling?

I only know EOLs in 300s with needle split, where nothing is guarding my low rrpm marging, except my FI yelling at me.

I would not expect any difference in mechanical(!) drag (or ROD) between demonstrating an EOL with needle split (possibly with recovery at 20ft) and doing a "true EOL" where the engine actually has stopped turning.
Is that view wrong, if yes, pls elaborate why.

nigelh 15th Sep 2017 14:33

I see your point . Where I think TC is wrong is that EOL is engine off landing . If you do an auto , it is an auto regardless of the engine state . You can just dump the lever with full engine and it is still in autorotation in my view ( aerodynamic ) .
I also agree that v few people demonstrate actual engine off landings partly I expect due to cooling off period but mainly I guess as it would be an added risk for v little gain !!
No doubt God will tell us otherwise.... a bit like USA v UK with settling / LTE etc etc I think we have got used to calling engine in idle an EOL .
Is it worth arguing about ?!! I rather foolishly tried to tell God that EOL is not relevant to the autorotation on the way down , where you have the option to keep the engine if you wish ( if it is still producing some power ) . An auto is an auto regardless!! End of !

Hughes500 15th Sep 2017 14:37

Reply

I have done thousands of EOL's to the ground with the engine at idle and with the throttle wound hard in against the stop if you don't as you pull full pitch the corrector gets the engine back to about 2000 rpm form 1500 ! I was saying I have had 2 engine failures in my 8000 hours of flying. First time it was while doing a PC with a customer, he wound the throttle off as we went into auto. I wound the throttle in hard against the stop and the engine stopped, height about 700 ft ( Before anyone asks I did this check on the ground and it didn't stop the engine ! ) I was surprised at the rate of descent, normally around 1600 to 1800 rpm depending on where the auto revs are set. We were comfortably over 2000 ft a minute
Although the engine in a normal auto is running there is an element of friction that keeps things turning. I was surprised in a genuine power off landing what a difference there was as I said about 200 to 300 ft a minute .
Hope that answers your questions

evil7 15th Sep 2017 16:19

Hallo all,

My question would be - if you have an engine with the throttle stuck full open, can you even enter an "autorotation" without shutting off the motor or would the engine with screaming rpm keep driving the gearbox regardless the freewheel and your pitch down?

Hughes500 15th Sep 2017 17:06

Evil

Depends where the throttle is stuck, what I mean is which side of the correlator linkages. As you may know the correlater on a 300 will try and open / close the throttle in relation to where the collective is. So if stuck at the hand grip then the correlator will look after rpm. More likely for the linkages to go at the injector itself.
I would suggest that if the throttle is stuck at full open as opposed to the setting for whatever pitch the blades / Map you are flying at then you have a major problem. The throttle is going to want to accelerate the rotor system, it maybe that lowering the lever may activate the correlator to close the throttle, if not then the rrpm is going to go off the roof as you decrease MR drag.
To contain NR you would have to lift the lever, bear in mind you can't enter autorotation as the engine speed is higher than the rrpm so freewheel won't come into play. Your only real option is to pull the mixture which is easier to do then the fuel shut off valve. By gradually pulling the mixture the fuel will go lean increasing engine rpm until the lack of fuel starves the engine. Now can you restrict the fuel flow to slow the engine, I doubt it as if you follow the last check of the day on shutdown in a 300, as you pull the mixture at about an inch out the mixture goes lean, hence the 25 to 100 rpm rise, pull out another fraction and the engine will die ! I would imagine pulling the fuel shut off valve will have the same effect.

nigelh 15th Sep 2017 17:25

Hughes ...why not ask TC . He will know the answer as he is our resident 300 expert !!
Presumably you didnt realize that it has an electronic fuel cut off as well did you ?!!
As you still actually fly helicopters and fly the 300 ( so did i instructing but that was 1000 years ago ) it is interesting to hear your take on the possibility of reducing the engine rpm by either careful use of cut off or mixture . I can only guess that if it can be done someone will have done it !!
ps TC is also wrong about us flying the same machine unless you also run an old Agusta Mk2 !!!

tottigol 15th Sep 2017 19:10

Has anyone considered the possibility of a freewheeling unit malfunction.

nigelh 15th Sep 2017 21:24

Two major failures within minutes would be unlikely. If so , what terrible luck . Hopefully we shall find out soon . The 300 is a great little machine with a good safety record as far as I am aware . V sad .

cncpc 16th Sep 2017 02:39


Originally Posted by Hughes500 (Post 9892732)
Reply

I have done thousands of EOL's to the ground with the engine at idle and with the throttle wound hard in against the stop if you don't as you pull full pitch the corrector gets the engine back to about 2000 rpm form 1500 ! I was saying I have had 2 engine failures in my 8000 hours of flying. First time it was while doing a PC with a customer, he wound the throttle off as we went into auto. I wound the throttle in hard against the stop and the engine stopped, height about 700 ft ( Before anyone asks I did this check on the ground and it didn't stop the engine ! ) I was surprised at the rate of descent, normally around 1600 to 1800 rpm depending on where the auto revs are set. We were comfortably over 2000 ft a minute
Although the engine in a normal auto is running there is an element of friction that keeps things turning. I was surprised in a genuine power off landing what a difference there was as I said about 200 to 300 ft a minute .
Hope that answers your questions

I've had the engine stop at the bottom of a practice auto. I can't remember the exact reason why, but it had to do with keeping some RPM on the way down after the needles split. I went to roll on throttle at the level off and there was nothing there. Just continued to the ground.

Is Dennis Kenyon on this forum?

Old Farang 16th Sep 2017 05:00

Hmm, I am now too ancient to fly anymore, but I just wonder how some people with correlators, electric fuel shutoff valves, hydraulic controls etc.,
would have managed with older piston machines that had none of them!

Cannot remember which way the H300 engine is mounted, but I do remember that my old Hiller was vertical. As an engineer I cannot agree about "friction" being the cause of a difference in ROD. But there will certainly be some differences in forces because of the gyro effect of an engine between running or stopped. May not be the cause, but it should be considered.


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