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Flyting
15th Jan 2007, 08:01
If anyone out there has had an engine failure :eek: and noticed the pre-failure warning sign i.e. gauge changes etc... besides the normal yaw and screeming horn and passengers, can you elaborate for eveyone who hasn't yet had the experience...:confused:

verticalhold
15th Jan 2007, 08:21
Large amounts of compressor stalling, followed by tot going off the clock one way and pressure the other way followed by the engine seizing. All in about 5 seconds. A labrynth seal had split and poured hot oil into all the important little places you don't want it. The comp stalling was bloody distracting due to the noise. Everything else was by the book. Engine went 2 kt above VToss, offshore at night. They did forget in training to warn of the secondary effects to underwear, heart rate and passengers.

gnow
15th Jan 2007, 13:15
I have had 6 single engine failures on the S61N and one on the Super Puma L1. Of the 6 engine failures on the S61N, five came without warning. Only one had warning when in a straight and level flight the fuel shut off valve closed by itself electrically(physically it is in the OPEN position). Until today Sikorsky could not explain why it happened as the valve is to remain in its last energised position. The engine flamed out about 30 sec later.
On the Super Puma L1, the lady whispered "fuel" followed by both booster pumps failed light on one of the engines.We still had plenty of fuel in the tank. Again within a short while the donk failed. Later I found that one of the pipe lines from the tank to the engine had came loose and disconnected!

tecpilot
15th Jan 2007, 13:48
On a long line operation with a MD 500 helicopter i was so stupid but lady luck shined on me...
I was working under time pressure to test equipment with very fast longline circuits over a mountain area.
Over radio my groundman told me that he was sure to listen some "unknown" noises. Stupid i was i told him anything was fine for me and better to shut up and to do his work :\ (life CRM :ugh: ) I feeled good, no caution lights or any other problems, no vibrations, ... Wearing a helmet and additional ear protections i couldn't hear any special noise.
2 rotations later (means about 4-5 minutes) this brave man strongly refused to work further with me and this helicopter and was not ready to connect new test tubes to the sling to stop my flying. Allways talked about "uncommon noises".
While hovering above the loading place and really angry discussing with him the engine failed suddenly complete. I was able to bring the ship and myself safe to mother earth. Luckily i was not in to high hover over the one and only flat and clear spot in the whole area suitable for an AR, the sling was unloaded, single person onboard, fuel tank nearly empty. :}

No question, i paid a lot of beer on the evening (may be a little earlier ;) ) to the ground crew and especially to my lifesafer.

In this case the Allison engine gave us a signal in form of a loud and wailing noise, but i as the pilot wasn't able ( and may be ready??? )to hear it!

After that on an other occasion the groundcrew talked again about noises and i was nearly immediately on ground := but in this case the noise was only a plastic strip trying to leave one of the blades!

Brian Abraham
15th Jan 2007, 14:46
Two failures in the S-76 (Turmomeca), one announced itself by a large explosion (well it seemed like it at the time) followed by smoke in the cabin - no prior indications, the other was just a soft pop - again no prior indications. In both cases bits had become detached in the hot end taking out the blades. Observed one in a S-76 (Allison), aircraft written up for being way down on trend so maintenance decided to do a power check, guess what, it let go in no uncertain manner and from the look of it very little would have been salvageable - perhaps the trend was trying to say something. Oh well, you live and learn.

verticalhold
15th Jan 2007, 14:51
B Abraham;

So far I've written on this thread about one failure, I've experienced three. If it seemed like a large explosion you can bet your life it was! When a turbine lets go it tends to do it in huge style. I still think the noise is the worst part of the whole event, but then I've never had a failure in a single.

VH

SASless
15th Jan 2007, 16:55
Smelled burnt oil aroma at shutdown....everything else perfect.

Refuelled....flew up to the top of a 10,000 foot mountain....no problems.

Landed and shutdown for an hour....cranked and picked up to a hover no problems.

Checked all was well but heard an "odd" but not worrisome sound....re-checked the instruments...all was well. Departed.

Once well away from the mountain....lowered the collective...."BOOM!", sudden yaw....noises from a Chinese/American Indian mix...."UGH...LEE".

Weird instrument indications....N1 was above idle, N2 was varied with collective, Nr went with collective movement somewhat normally....landed with no damage beyond the normal laundry issues.

Seems a main bearing in the engine had gone....turning the rotors by hand turned the engine.

There is no such thing as a "standard" engine failure.

Gordy
15th Jan 2007, 17:05
I have had 6 single engine failures on the S61N and one on the Super Puma L1.
Who did you piss off :eek: ---Remind me to never fly with you!!! JK

Oggin Dodger
15th Jan 2007, 18:36
Had one in a Lynx with no prior warning, the EPCU simply shut the engine down. Had another one in a Lynx which doesn't really count as we elected to shut it down following engine oil pressure falling rapidly. Had another in a Sea King off a ship at night which was reported by the back seat crew observing a load of sparks coming out of the exhaust past his window before it finally let go gently.

All three completely different.

Floppy Link
15th Jan 2007, 19:18
Had one in a Twin Squirrel during a vehicle pursuit on a very windy day...cops lost sight of the car and I saw it out of the corner of my eye, fastest way for them to get the camera back onto it was to hover downwind, so the aircraft was twitchy in yaw already.
Slightly larger twitch and heard the interference of the igniters over the intercom. Looked in and the auto relight was on, and the number two engine guages were all returning to normal.
Nothing found by the engineers, conclusion was a big gust had blown out the flame...auto relight's a great thing.

md 600 driver
15th Jan 2007, 19:35
only had one and there was no warning
but when it does happen it goes very quiet quickly

NickLappos
15th Jan 2007, 19:38
I had a total of 17 engine failures.

In about 1/3 there were clear signs, such as chip lights, bad noises or failing power (increasing N1 and TGT for the same power).

About 1/3 were part of a stall sequence, with rapid temp climbing, noises and then flameout (or I pulled the lever back).

About 1/3 were just plain failures, with the power sliding back rapidly.

SASless
15th Jan 2007, 20:17
Nick,

That is an impressive record....perhaps you could add to the account a wee bit and explain why so many? These failures due to "experimental" work on new technology engines?

I had one engine failure in singles.....and two in multi's....both multi's being from FOD (one swallowing a Dzsus fastener and the other a hit from a .51 Cal.)

nigelh
15th Jan 2007, 21:07
1 may be bad luck :{ but 17 has to be careless:= Can we have a party when you hit the big 20???
I only had one , Bell47G3 Egypt it just stopped.....bit like turning the ignition off. Nice soft landing on the sand tho:D

Brian Abraham
16th Jan 2007, 01:40
Forgot a T53 failure. Sitting on ground and oil pressure light came on, scan of pressure gauge confirmed zero, immediate take off, climb to 500, accelerate to 100Kt, other aircraft reports thirty feet of flame out of tail pipe at which time the chip came on, into auto, engine quit in the flare. From go to whoa, two minutes max.

NickLappos
16th Jan 2007, 04:21
SASLess,

Lots of work with X engines, mostly. Some fod, some with bullet holes, one with a pair of duckbills that went right into the combustion chamber, thanks to a careless E-4.

Experimental installations, experimental fuel controls (flew one helo with two controls for each engine - switched in flight!) stalls, exhaust streaking, and the like.

Keeps you on your toes - boredom is not one of the occupational hazards!

Bravo73
16th Jan 2007, 09:16
Forgot a T53 failure. Sitting on ground and oil pressure light came on, scan of pressure gauge confirmed zero, immediate take off,

Out of interest, Brian, why not just stay on the ground if you had a problem? :confused: Or were things a little, er, 'hot' at the time?

ShyTorque
16th Jan 2007, 12:35
I've had lots of engine failures.

Thankfully I have noticed that most of them begin with a "Heh, heh, heh! :E " from a simulator instructor....

;)

SARREMF
16th Jan 2007, 19:38
Total of 7.

Oddest was on a Sea King when the engine ran up to max but the torque dropped to zero. Aha! Obviously a free power turbine failure. No. Turned out to be air in the inlet guide vanes. They moved - because of the air [more bubbles really in the fuel that is used to control the inlet guide vanes position]- this altered the mass flow of air through the engine and importantly out the back end. This reduced the speed of the free power turbine. The good old flow control unit for the fuel detected this and poured more fuel into the engine - the gas side spins up trying to reestablish the balance - which it can never do. Net effect an engine spinning up with a compensatory loss in torque at the same time.

Took us ages to work that out.

One day I'll tell you about the apparent double drive failure

SASless
16th Jan 2007, 21:07
Sounds about as interesting as having the first of a kind, N2 overspeed shaft failure on a Chinook. Just prior to touchdown with two students on their second ever Chinook flight, the Nr went way...way....way high along with its torque and N1. Standard drill was to control Nr with application of collective (Thrust Lever) and disable the Normal AC powered beep trim and recover using the DC powered Emergency Engine Trim system.

To add to the fun.....this particular aircraft did not have any Grenade Pin rings wired to the Circuit Breakers (An infield soldier Mod that made finding and pulling the affected CB much quicker and easier) and with the two new Studes sitting there, mouth agape...asking what CB? Where is it? Things got a wee bit busy for a while.

We got the CB pulled, beeped to minimum, and realized with some merriment, the emergency drill failed to make any change whatsoever. We still had two engines at max power, one at topping, and one that went beyond topping and had gone to its pure ol' I cannot do any more power.

The Nr was still way high....like blade slinging high...thus pulling the bad engine off line by shutting it down was the only way to improve the situation.

By the way....did I mention the rate of climb we had? We passed thru a solid overcast layer akin to a shuttle launch and were now VFR on top still climbing like blazes.

The choice of engines to shutoff was a bit interesting....the only difference was the N1....which showed one engine at 105% and the other at 112% with a very small split in torques...figuring the high Nr was a small clue to what was going on....I pulled the high side engine lever back to ground idle and got a decrease to idle....then shut down that engine while regaining normal control of the Nr.

IHL
16th Jan 2007, 22:55
While taxiing for take-off in a 172 with the Lycoming 320 H engine I noticed that the oil pressure was progressing towards ZERO. I returned to the ramp and upon further inspection the oil filter was filled with metal. The oil pump had come apart.

I was flying A 76 with the Rolls Royce (ALlison) 250-C30 engine when It started making a loud howling noise. We continued to a landing and while taxing in we got a chip light. Further inspection revealed a bearing was coming apart -not sure which number.

I have had other countless chip lights without resultant engine failures.

I currently operate (fly) an aircraft with a RR 250-C20 and another aircraft with a Pratt and Winney PT6. I haven't had a chip light for quite a while. I hope I didn't jinx myself!

Graviman
17th Jan 2007, 11:39
Interesting thread - certainly shows that after the engine installation development bugs are sorted, there is still much that can and does go wrong.

Any new project is a collection of faults waiting to happen. The job of the engineering team is to find them before the customer does. :}

Mart

Hughes500
17th Jan 2007, 16:54
S300

Magnetos packed up - both did mag drop ok ( about 90 a side ) after 5 mins flying ac started missfiring - yawing 30 degrees left and right a couple of times. Run on landing in field, with engine running not enough power to hover.

S300

Lifted out of a clearing in a wood to 100 ft, transition into forward flight, clear wood. Engine miss fires again yaw left and right by 30 degrees. Enough power to fly but with rod of about 200fpm. Run on landing about 600m away.
All bottom plugs had lead fouling - after 1 hour of teaching ex 26. Student was most impressed knows what to do after he said very calmly "you have control":eek:

Dis-Mystery of Lift
17th Jan 2007, 19:06
Brand new EC130,
Belly panel screw chaffed into wiring loom.....115kts @1000ft...Floats go bang which I cant see.Due to large "Bang" slam collective down and get rather large nose down attitude (Floats and Auto) Christmas tree on warning panel and funny gongs going off in Headset.Engine has gone to ground Idle and a passenger says "your floats are out" I think I replyed thats the least of my :mad: worries. Full auto onto ground and still have stretch marks on my butt from the seat cushion.
Screw had taken out both Fadecs and Ebcau.
So much for new technology

AdamFrisch
30th Jan 2007, 13:30
H269 made a clattering noise for about 2 seconds, then totally seized up and went from 2300rpm to zero immediately. Helicopter yawed violently.

Apparently a valve had come loose and lodged in the cylinder causing an immediate stop. Engine and underwear had to be replaced.

Impress to inflate
30th Jan 2007, 17:06
The last engine problem I had, the "POWER" light on the faulty engine flashed several times very briefly followed by the associated engine running down to ground idle. Engine runs down, shut it down. AS332L.

Thomas coupling
30th Jan 2007, 22:45
One wound down to FI whilst in the hover over Sea state 6.
One exploded when a compressor blade went for a walk.
One surged and blew itself out.
One was taken out by a wave while I was burning and turning on deck at night.
One shut down 'cos I hit the fire button instead of the ignitors (adjacent to each other) on shutting the engine down :ugh:
All of these happened on twin engined helos during a span of about 3000hrs.
I also have 3000 on singles - and not one of those engines as much as hiccupped:D

SASless
31st Jan 2007, 01:13
Sea Kings or Lynx's TC?

Thomas coupling
31st Jan 2007, 14:36
Sea Kings mainly.

fluffy5
31st Jan 2007, 15:26
Flying a Robbie, 18 minutes into the flight after picking it up from the maintenance department the oil light, and then the oil pressure gauge reducing. Called Birmingham Radar to say precautionary landing, powered descent, landed and got out to see oil spraying itself all over the engine.

Again a Lycoming 320, oil filter. Yet the maintenance company were rather keen to get there and quickly swap the filter, and upon inspection the oil filter was perfectly intact, the mount was not showing any signs of wear.

Contacted the CAA within the time allowed for an MOR, and then contacted the maintenance company to see if they had filed a report or even said anything, and they answered 'We don't need to bother about that' !!!!!

Flying Robbies can be fun ?:ugh: