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pilot_tolip
2nd Aug 2018, 15:55
Not for training purposes, but in a real situation. Who has done an autorotation? Why did you need to do the autorotation? I'm interested to hear your experience.

paco
2nd Aug 2018, 16:14
Compressor blew out over a Scottish loch, and another one flying across the main runway at Manchester, then a night one. All in 206s.

SASless
2nd Aug 2018, 16:29
Hughes 500D....Engine lost a major bearing as I departed Mount Neuhaeauser (just shy of 10,000 feet) in Alaska (near Tok Junction) just at dark.

Landed with no damage to the aircraft.

Far too high to contemplate all that was going on and what wasn't under me for a landing site.

Hovering in a Chinook over a mountain called Gia Rhe near Xuan Loc, while dropping off a sling load....one engine had a fuel control problem and the second engine had a Compressor Stall.

That was a very close call. Think I shall take a drink while I ponder that minute or so flight once again!

Landed at the base of the mountain with no damage.

Fareastdriver
2nd Aug 2018, 18:49
2nd solo in a Whirlwind 10. a jet propelled S55 to our cousins. Cruising back to base at about 200 ft. and the fire lights come on accompanied by smoke filling the cockpit.

Go through the fire drill, push out a Mayday and turn into wind.

I was then confronted by a walls of splintering trees and writhing earth as a two acre field heaved itself across the scenery and presented itself directly in front of me.

A quick prayer to Bacchus and I landed.

chopjock
2nd Aug 2018, 20:46
Enstrom 280C Stuck throttle, chose to shut down engine to avoid blowing it up, no damage to ac.
Enstrom 280C Tail rotor failure, wound throttle to idle incase I needed it later...no damage to ac
Hughes 500C Fuel starvation, heavy landing due to poor technique on a hot day, 3 up and no wind.

cavuman1
2nd Aug 2018, 22:00
Previously posted on this forum in February of this year, I repost since I relive this moment infrequently in the obtunding silence of the middle of starless nights. This was the first and only actual autorotation in which I participated and I hope and pray the last!

- Ed :ok:

I was a relatively low-time PPL-SEL (maybe 200 hours) in 1979 when a friend who was flying Evergreen 206 LR's to a test oil rig off the coast of Georgia said he would teach me to fly "frantic palm trees". I had accumulated four hours and could hover clumsily but handle other flight regimes satisfactorily when he called one Sunday morning to ask if I'd like to bring my wife and 9-year-old son on a sight-seeing tour. Hell yes, I would!

We flew for an hour doing some low-level (10') high-speed passes over the marshes, rivers, and ocean, and some fairly high G aerobatic work. We were on long final, three minutes from KSSI (McKinnon St. Simons). We had received permission to land and were descending through 2,000'. My "friend", a 6,000-hour 'Nam pilot who was flying right seat, came over the intercom and said "Watch this!" He reached for and cycled the Emergency Fuel Cutoff switch. The annunciator panel went from green to orange to red! He had starved the engine of fuel and we were too low to get a restart! This was going to be a genuine autorotation. I turned to my family in the rear seat and yelled "Brace! Brace! Brace!" https://www.pprune.org/images/smilies/eek.gif

We hit the beach, the skids dug in, the helicopter tipped forward, the main rotor clipped the tail boom off in a neat decapitation which spun us a full 360 degrees. My wife grabbed our son in her arms and exited to the left; the end of still-spinning main rotor puffed up her hair as it cleared her by an inch! I fumbled with my 5-point restraint for what seemed like hours, then ran like the devil. https://www.pprune.org/images/smilies/wibble.gif

The starboard fuel bladder had ruptured and was spilling jet-A near the exhaust. The T.O.T. was ~ 700 degrees, the VSI pegged at 2,500 down, and the ASI at 40 knots. We were lucky to be alive...

Some serious adult beverage consumption coupled with general prayers of thanksgiving to anyone listening followed that afternoon, but bright and early the next morning I went alone for an hour's introspective solo in my 152. Had I not, I am not certain that I would have ever flown again. https://www.pprune.org/images/smilies/puppy_dog_eyes.gif

I have abseiled and was an ardent skydiver until my then-wife put her foot down and forced me to choose between her and my T-28. I have hung by one foot and one hand 50' above the stage while changing gels and bulbs in theatrical lighting. But get me on a 6' step ladder and it's time for vertigo and acrophobia! Go figure... https://www.pprune.org/images/smilies/confused.gif

- Ed https://www.pprune.org/images/smilies/smile.gif

SASless
2nd Aug 2018, 22:15
My "friend", a 6,000-hour 'Nam pilot who was flying right seat, came over the intercom and said "Watch this!


One should be very careful how you choose One's Friends!


As a famous American once said...after the low level flying and throwing the birdie around.....when he said that to you....."Here's Your Sign!"!

Ascend Charlie
2nd Aug 2018, 23:49
He reached for and cycled the Emergency Fuel Cutoff switch.

Unbelievable stupidity.

Did you land a bunch of knuckles in the middle of his face when you next saw him?

SASless
2nd Aug 2018, 23:55
AC.....in this we agree in principle however not in degree.

Post Crash....he and I would have gone to Hospital.....him for internal injuries and me to get my foot from out of his ass.
:ok:

BOBAKAT
3rd Aug 2018, 02:12
R22 : take off from beach over water, 30ft/30kts, engine cut off....The shortest autorotation registered.....:O But still alive with the studient...Just swimming to reach the shore...

fijdor
3rd Aug 2018, 02:33
#1) was with B47, I had a grand total of 25hrs. I started it and the instructor finished it. #2) Again with the same B47 I had about 80 hrs total (still on my pilot course) and was by myself and it was a success. Some months later another student had the same problem with that B47 but wrote the thing off, his auto didn't go to good. #3) was with a FH1100 the engine quit at about 300ft the auto was a success but in small trees, had to get new blades. #4) was with a B206L the engine went to idle by itself (fuel control decel) again successful autorotation. The next couple of full autos were done when I decided to turn throttle off myself due to fires, #5) One B47 engine on fire, landed in a field successful auto but damage due to fire. #6) B206 gas heater fire in winter, landed in a newly cut powerline, successful auto but back end of the 206 was damaged from the fire. Had 1 tail-rotor failure in flight FH1100 (fixed pitch) landed successfully but slight damage to the skids from the running landing. Also did one long auto, B205, more like a mixed of autorotation and engine on from 19500ft back down to 13,000ft where staging was. Engine oil pump shaft sheared.
Also had one engine out on a B212 at about 12000ft but managed to come back to base (in Ecuador). Lost an engine in 2 occasions in B214ST and one precautionary shutdown again in a B214ST which is not really an issue in a ST, you don't say a word and nobody will notice.
One complete loss of electrical power in a 214ST, not one system was left on, no scass, no nothing only 2 engines left, it is a little bit of a challenge to land the beast with nothing left on. On this one didn't need to say a word, everybody noticed. lol

JD

John Eacott
3rd Aug 2018, 07:33
fijdor, 6 is 7 too many!

I had an interesting B206 engine failure on short finals to the World Trade Centre helipad on the Yarra River, Melbourne. With nowhere else to go but the pad (the river wasn't a preferable option) I was happy to be making a steep approach with the knowledge that I'd make the pad in an emergency.

The C20 compressor had lost a stator in the fourth stage which corncob'd the remainder of the compressor; the remainder of the power train kept running at idle so having arrived on the deck with an armful of collective it presented a puzzling set of instrument indications! As an aside, Rolls Royce were less than helpful as the case halves were only ~200 hours and failed due to corrosion below the liner yet they claimed it was lack of maintenance on my part. A year later and some 6-10 identical failures later in Australian Army Kiowas, R-R paid out the Army: my cost was into six figures and was denied compensation :(

fijdor
3rd Aug 2018, 13:40
You are right John, but the first 2 autos, especially the first one, gave me something right at the start of my career that stayed with me till today and it is real confidence that I could deal appropriately to an emergency when it shows up. It was a beautiful late summer day, no doors on the 47 and we were in the practice area, lots of open space. I was on a climb and at about 7 to 8 hundred feet the engine quit. The thing is the instructor was turned sideways leaning outside the 47 with both feet on the basket that we had on the crosstube. He told me afterward that he thought I was playing when the engine quit. But he did get back in and took control but after I was well established in the auto. Did get a free beer out of that one, he said it was a lesson learned for him too.

JD

pilot_tolip
4th Aug 2018, 06:17
Thank you, everyone. Very useful to know.

hihover
4th Aug 2018, 07:26
I made a forced landing (autorotation) when I was about 20 hours out of my pilot's course which taught me many lessons within a 1 minute period, it also frightened the life out of me but having read fijdor's story and Cavuman's, they frightened me even more, ......my story pales into insignificance.

Ascend Charlie
4th Aug 2018, 10:55
Jeez, how did I get through 15000 hrs and never have anything worse than an N2 runaway in a twin?

You guys must be making up for my less-than-the-average rate of engine failures. Or maybe the people I worked for had better maintenance? Who knows.

Vertical Freedom
4th Aug 2018, 12:11
On the dreaded 'D' date I completed a turn around inspection before departing the Gamghadi Helipad for VNNG in an AS350B2. Take-off time was 1240nst/0655utc. With 5 PAX, 70kg cargo & 280litres fuel. As there was local weather; rain showers & hilltops embedded in cloud I elected to fly following the Karnali River to overfly VNSK, then onto VNNG. I had completed a power assurance check earlier that day & the engine health was above par. Operations were normal during the flight & I was flying over the Karnali river at around 1,500’agl. At approximately 1306nst/0721utc the engine chip caution light came on. About 2 seconds later the engine oil pressure warning light came on, at this same instant the cockpit completely filled with smoke, so I had totally lost all visual reference! Then in the next 1 second a sudden & massive yaw to the right indicated that the engine had failed. Next the Nr low alarm rang as I was lowering the lever to enter autorotation. At this stage the smoke was so thick & heavy that I was unable to see the instrument panel, nor the ground outside. Visibility was IMC, completely zero inside. I screamed at the PAX to open their windows & I kicked in a bunch of left pedal to side slip the machine to force extra airflow through my window to force ventilate out the smoke away from my area so that I could see the panel & assess my autorotation options. Once visibility had partially returned sufficiently inside, I could see that the Ng was 0%.I then determined that my auto-glide profile would put me directly into the Karnali River, but just beyond my glide range was a suitable rice paddy for landing? So I elected to raise the collective to reduce Nr below the low red line in an attempt to extend the glide profile to my intended forced landing spot. At one time I attempted to return Nr into the green range, lowering the collective lever but it was clear to me that I would not make my selected landing spot. So I further reduced Nr to ensure I would reach my forced landing spot.Once established on this glide profile I gave a MAYDAY call stating; MAYDAY MAYDAY MAYDAY Helicopter 9IW engine failure going down 1 mile North of Munma Barracks.The smoke continued to hamper visibility, making judgement difficult. I was now around 100 meters from the pad & started my flare, then levelled as the aircraft came just over the rice paddy & I cushioned on. Due to the uneven ground (rice paddy levy wall) the skids collapsed during the ground slide & the tail-boom partially separated. The landing was slightly heavy due to Nr being low, but in my judgement without the Nr being reduced the glide range would have been insufficient to reach the rice field & we would have crashed into the boulders & raging monsoon flooded river below where survival would have been zero. :O

All PAX safe & uninjured, only injury was me....................................emotionally :rolleyes: Machine repaired & flying again :D
https://cimg3.ibsrv.net/gimg/pprune.org-vbulletin/2000x2000/80-p1050961_5e8647b80e836f14bb7db7856f2108c856afaecf.jpg

https://cimg0.ibsrv.net/gimg/pprune.org-vbulletin/2000x1536/80-2photo_ddd6a2241cf9d169f57048b821d28e2740a0cae3.jpg

https://cimg2.ibsrv.net/gimg/pprune.org-vbulletin/2000x1536/80-3photo_87311f35f41979c07fa19bc1ee7f0e57d6dfa1b1.jpg
Just another day, another dollar, less tax :eek:

SASless
4th Aug 2018, 12:27
VF....but look at the wonderful story you have to tell!

parabellum
4th Aug 2018, 12:54
AB206 in Indonesia 1968. An harmonic set up around the third stage compressor with an engine bleed that was open at start and gradually closed as engine spun up. Consistency of compressor blades turned to glass and shattered. This was in the cruise. Managed a safe landing next to a Kampong alongside a river, still have lower back problems. Aircraft back in the air about a month later when replacement engine arrived. The fault was known but the modified engines were all going to Viet Nam.

albatross
4th Aug 2018, 14:37
I had a couple.
Most interesting 206L at gross weight... engine exploded.
270 auto from 700 feet to a sandpit. Hot day no wind. 1000 ASL. Got it stopped because I could not do a run on but bent the rear cross tube a lot and the FWD cross tube a little because we hit hard. I got the aircraft level from the turn at about 50 feet.
Called the boss at 0800 on a Sunday morning and told him I needed some spare parts.
He said "What do you need?"
I said "A new engine and 2 cross tubes!"
He said " How much fuel did you have and how much oil?"
I said "530 lbs of fuel and full oil which is burned blacker than Sh*t. The engine exploded!"
He said "Well done! parts will be sent immediately!"
I was back in the air in 24 hours. LOL
I should have kept the RPM a little bit lower in the turn and the airspeed a little bit higher but always said that what saved us was that in training we always did full on outos.

SASless
4th Aug 2018, 15:47
Sounds like a very good job....cross tubes are cheap....the engine was not your doing....and no medical bills.

I suppose a dry cleaning bill for your seat cushion perhaps.

albatross
4th Aug 2018, 16:08
No cleaning bill but the very afraid passenger in the front seat was a bit of a distraction! The only injury was a bloody nose when he accidentally grabbed the collective in his thrashing around. There was a guy in a 500 about 1/4 mile behind me who saw the event and landed just in front of me as the rotors were slowing down ( I kept the pax in the aircraft until they stopped ) His comment on the radio : "WOW was that ever neat!" He told me later that he was very impressed with the explosion of the engine. LOL

MightyGem
4th Aug 2018, 19:39
At approximately 1306nst/0721utc
Shouldn't the minutes be the same, or were you in some weird time zone?

sycamore
4th Aug 2018, 21:17
Had 3 real autos #1 tail rotor and gearbox departed,,auto`d onto a pimple and burst a mainwheel on a treestump;
#2 week later,engine rundown on way to a Carrier,just made it to a beach at min.rrpm.
#3,about 13 months later,engine surged by new co-pilot(later to be a Gp Capt. Station commander) mishandling on approach to a hilltop LZ at about 30 kts..
No personnel injured,all a/c returned to service after repair.
Pictures are on p15/#294 of``Views from the cockpit`..not the videos thread....

meleagertoo
5th Aug 2018, 12:41
Not much of an event compared to the above but;

As a stude on the Bell47 we were practicing AOLs with the aiming point being a metre square concrete slab set in the grass which we were expected to place between the toes of the skids when the cab stopped.
Shortly after the auto was entered and throttle retarded the stick stiffened right up and I called "hydraulic failure". The beefer knew what had happened and just said, "slab between the skids, please". Never having done an eol with no hydraulics made this an interesting few moments and the silence after stopping (straddling the slab), plus the woosh - woosh and whine from the gearbox told the story - and why after the 3Gb1 the hydraulic pump was moved from the engine to the gearbox!

RVDT
5th Aug 2018, 13:17
ALL EOL's prior to the 3B2 were with HYD OFF. Why kid yourself?

pilot_tolip
6th Aug 2018, 11:39
Thanks, everyone that's posted. Very interesting and useful to read.

Lt. Kije
8th Aug 2019, 14:25
RotorWay 162F. Godawful bang and a smack into the bulkhead behind me. I put her into autorotation and picked out a spot to land. On the way down I noticed that the engine, while very low, wasn't quite dead. I was able to roll up enough to resume flight and headed for the barn when the student said, "hey - do you smell fire?"

Down goes the collective again and we're back into autorotation, only this time I curve the path so I can look behind to see if there's any smoke. There isn't and I start smelling what my student did - fried drive belt. Oh, good. We're not actually on fire in a fiberglass helicopter. I nursed the power back on and got us home, terminating in a 6" IGE hover taxi to the hangar.