GA Aircraft ditching - Irish Sea - 16th Dec [Archive]

A330ETOPS

16th Dec 2009, 14:47

News in from 'The Visitor'

PLANE carrying one person has ditched in the sea off the Fylde coast.
The female pilot sent out a May Day to Blackpool's air traffic control after experiencing engine trouble.

The incident happened just after midday.

It was feared the plane could be forced to make a crash-landing at the resort's airport.

It was finally forced to ditch in the Irish Sea 22 miles off the Blackpool coast.

The pilot was due to land at the Isle of Man after travelling from Guernsey.

She was picked up by a rig supply boat and taken to a nearby gas rig.

CHC Scotia have sent out helicopter to bring her back to Blackpool where she will be taken to Blackpool Victoria Hospital for a check-up.

A spokesman for Lancashire Police said: "All services are on stand-by after the pilot reported engine trouble."

Sue Kendrick, from Blackpool Airport, said: "We had reports a one-man small aircraft was having engine troubles.

"It has been forced to ditch in the sea and the person on board has been picked up."

flyvirgin

16th Dec 2009, 14:56

Great news, she survived, I hope she makes a speedy recovery and gets airbourne again soon!:ok:

fireflybob

16th Dec 2009, 14:56

That's good news! Don't suppose you'd last too long with the sea temps as they are at the moment.

A330ETOPS

16th Dec 2009, 15:01

Was worried about that myself when i heared the news! Good to hear she did a good job ditching it

jayteeto

16th Dec 2009, 15:01

I think it was a twin engine ac according to ATC. Two failures??

junction34

16th Dec 2009, 15:09

Reported now as being a Twin Commanche.

Manx.net with IOM Department of Transport Press Release (http://manx.net/default.asp?id=18&articleid=9590)

-j34-

ftimesf

16th Dec 2009, 16:22

It's cold in that sea in summer let alone this time of year..
How great to see a speedy recovery with no loss of life.:D

PH-SCP

16th Dec 2009, 16:46

Great job, cool:D airmanship.
Not that it is important but since it was "Alpha November" and Manx registered, putting one and one together, the airplane that qualifies mostly is M-ALAN, a PA.30 Twin Comanche....

http://img402.imageshack.us/img402/9259/malan.jpg

Phil Space

16th Dec 2009, 17:23

I was banned for a week for doing that:ok:

S-Works

16th Dec 2009, 17:28

Yeah, I think you were banned for doing it when someone died Phill..........

JUST-local

16th Dec 2009, 17:46

Same aircraft and driver came into Blackpool a few years back on one motor!:}

junction34

16th Dec 2009, 17:58

I think there's only one Twin Com on the M register, but can't be sure so there's no guarantee the aircraft in the image above is the incident aircraft, though the registration does almost fit with an earlier post.

It will be interesting to find out if the pilot had an immersion suit or raft - I would have thought an immersion suit to be less likely with a twin than a single, in which case proximity to the standby vessel would be a very significant factor.

Timothy

16th Dec 2009, 19:06

It does make one wonder what the common cause of failure was. There is, of course, an obvious explanation, which would not compute with the heroine status of the pilot, so it must have been something more subtle. Fuel icing (http://www.pprune.org/private-flying/397610-fuel-icing-avgas.html) maybe?

7AC

16th Dec 2009, 19:54

It's a mystery, but give it time and the mystery will solve itself!

karl414ac

16th Dec 2009, 22:47

A job well done to everyone involved!!!

Not trying to be the AAIB on this but it has been reported to the public as a double engine failure, the first thing that sprung to my mind was maybe a fuel selector issue with it having tip tanks (Please excuse i am not 100% sure on the fuel system of a PA30 ). Fuel icing may have been the issue but would it not of shown earlier in the flight. A friend of mine down south who has a PA30 (with out tip-tanks) who i contacted to make sure they werent involved came out with when i mentioned it was reportedly a double engine failure that it may of had ice blocking the tank vents which he said can be common on this type.

At least the pilot lives to fly another day and tell the tale.

Once again thumbs up to all that assisted the speedy recovery!!!!:ok:

Karl

Captain Stable

17th Dec 2009, 07:17

karl, you said it yourself. Don't be AAIB. Don't speculate. You have NO idea what happened, and if you don't even know the systems of the aircraft don't try to be clever and quote what some bloke down the pub said that someone had said to him in the queue at the bookies...

Justiciar

17th Dec 2009, 08:04

don't try to be clever and quote what some bloke down the pub said that someone had said to him in the queue at the bookies...

A quote from an owner of a similar aircraft who may have significant experience of the type hardly falls into that category!

Whatever the cause, the ditching sounds to me like a hugely impressive bit of airmanship and piloting skills. Has the aircraft been recovered? I suspect perhaps not!!

JAR FCL

17th Dec 2009, 09:07

I don't expect recovery to be a major problem. With those empty tanks I'm sure the aircraft will float for quite some time :oh:

tarnish26

17th Dec 2009, 09:47

JAR.....naughty, naughty...!!! One huge bit of luck in her favour was the weather conditions at the time, with the big high over the UK little wind and therfore flat sea for the past few days.........a differant out come in 30kt wind and 3 metre sea!!!!

Captain Stable

17th Dec 2009, 10:48

I suspect she was wearing an immersion suit - if so, very good planning.

When I did my HUET course, I was told that unprotected survival time in UK latitudes in summer was about 2 hours, in winter about 20 minutes (if you're lucky).

flybymike

17th Dec 2009, 11:38

Rumour on another forum says no survival gear being worn

vanHorck

17th Dec 2009, 12:13

I hope she reads PPRUNE and will care to tell her full story here.

One hell of a woman!

JAR FCL

17th Dec 2009, 13:17

Lets wait for the AAIB to produce some findings. I suspect they might not find too much wrong with the aircraft, or too much 100LL remaining in it.

Captain Stable

17th Dec 2009, 14:04

Dunno if theyll find anything wrong with the aircraft or not - it rather depends whether they've got scuba gear or not... :rolleyes:

And that's the second time you've made a scurrilous, baseless accusation. Would you want people to gloat and cast aspersions over any incident in which you are involved in the same way?

jayteeto

17th Dec 2009, 18:43

Just watched a report on the local news here, sorry I can't remember the ladies name but her hubby Alan Burrows should be known to a lot of you. Alan was interviewed with her. I met him a few years ago at OBA in Florida while I was hour building pre-RAF discharge. She was wearing a dry suit and got into the dinghy before rescue and seemed very calm about the whole thing. Whatever the cause, she was well prepared for disaster and obviously ditched well and got out safely/well kitted. :ok:

Cows getting bigger

17th Dec 2009, 19:02

Captain S, it may be scurrilous but can you recollect the last time any MEP had a double engine failure that, at very least, didn't have some form of pilot contribution? :)

PS. When I screw up (which, as a pilot, is almost inevitable), I'll quite happily sit by and watch Proone produce at least 5 pages of speculation. :ok:

IO540

17th Dec 2009, 19:18

can you recollect the last time any MEP had a double engine failure that, at very least, didn't have some form of pilot contribution?It depends on what you mean by "pilot contribution". I know a man who was flying a Baron and got fuel icing at ~ FL200 over the N Sea. The engines did not restart until 2000ft and he was still > 100nm away from anywhere.

The day after, he put it up for sale.

So it doesn't have to be fuel exhaustion, though it could be argued that in that case it was a failure to add IPA or whatever.

I know sod-all about twins but I know that some of them have "interesting" fuel systems with various fuel metering mismanagement options.

tarnish26

17th Dec 2009, 19:29

Dramatic rescue of Fylde air crash pilot - Blackpool Today (http://www.blackpoolgazette.co.uk/blackpoolnews/Dramatic-rescue-of-Fylde-air.5920339.jp)

IO540

17th Dec 2009, 20:16

Good work :ok:

Shame about the reporting....

Emergency services from across the Fylde were placed on full alert as fears grew the plane - suffering engine problems - would crash on land.

still, at least they are consistent. Maybe things are improving though... no mention of nearly crashing into hospitals or convents.

:yuk:

fernytickles

18th Dec 2009, 01:25

Captain S, it may be scurrilous but can you recollect the last time any MEP had a double engine failure that, at very least, didn't have some form of pilot contribution?

And I thought I had a crap memory.....:}

Airbus A320 double engine failure, landed in the Hudson not very long ago

Boeing 777 double engine failure, landed just short of the runway at LHR, also not so very long ago....

Cows getting bigger

18th Dec 2009, 07:12

You do have a crap memory. I don't recollect either the A320 or 777 being MEP (Multi Engine Piston). :}

Captain Stable

18th Dec 2009, 08:25

And now you're being silly. It doesn't matter a damn whether it's piston or jet or turboprop or elastic band.

There are all sorts of possibilities for double engine failure that are no fault of the pilot.

What's more, I have limited faith in most MEP's ability (and in the case of some MEP's no faith at all) to remain aloft even with a single failure. Does anyone here know the single-engine stabilising altitude for a Twincom? I don't, but I know that in a BN2 it's sea level.

I also have no faith whatsoever in the abilities of the press to get the details right. To 99.9% of journos, a multi-engine aircraft going down after engine failure HAS to be all engines failing.

My point is that there is no evidence whatsoever (yet?) of pilot error in this case, that there are several possibilities that would have this result without any pilot error at all, and that for someone here TWICE to accuse the pilot in this case is uncalled for as well as being a possible libel.

Timothy

18th Dec 2009, 08:47

Last time I mentioned that I recently had a single engine failure (actually disintegration) in an MEP at MTOW and that the result was completely uneventful resulting in a perfectly calm landing at maintenance base I was banned for a week.

There is presumably a conspiracy among PPRuNe mods to deny that MEPs can fly on one engine.

See you in a week guys :rolleyes:

IO540

18th Dec 2009, 09:17

I know that in a BN2 it's sea level.

How can it be used for public transport? With zero SE ceiling one may as well use a PC12 whose SE ceiling is also sea level...

Flyingmac

18th Dec 2009, 09:44

Granada Regional News | Granada Reports - ITV Local (http://www.itv.com/granada/lucky-escape84344/)

ManxLadybird

18th Dec 2009, 10:04

Ladies and Gentlemen, Thank you for all that you have been saying. Whether good or bad at least it is getting people thinking.

I did indeed ditch in the Irish sea. I was about 38 miles from IOM when my right prop had a runaway, it was overspeeding in excess of 2800 rpm and I could not stabilise it. The MP was low as well so I did not have much to play with. I felt it was uncontrollable and shut it down.

The PA30 can fly perfectly well on one engine so I decended to 4000 ft to get out of the cloud layers and diverted to Blackpool. About 6 minutes into my divertion my left engine lost power. My MP was down to 17 inches. I did all the checks changed fuel tanks, cross feed, electrics, boost pumps etc. No go.

D & D wanted me to try for Blackpool 18 miles away but I would not have reached there. I was near the oil rigs so elected to land in the vicinity. I spotted the support ship and ditched near it. I got out and had to hold onto the life raft. There were no steps on the liferaft and no way to pull myself in.

The oil rig helicopter was hovering nearby to spot me whilst the support vessel rescue craft picked me up. Once on the ship I was checked out and the RAF Seaking from RAF Valley winched me up and took me to Blackpool. I was checked out at the Hospital there and ok to fly home on Manx2.com's aircraft. All the emergency services and the police were fantastic and couldn't have been more helpful.

Lots of things were in my favour. In my training as a commercial pilot it was instilled 'fly the aircraft'. Sort out the problem and then make a decision and stick to it. This is what I did. My husband insisted on me flying in an immersion suit. Thanks to him, it helped. The weather was benign but cold. The sea had slight swell. If the wind had been greater than the 15 or so knots the waves would have been bigger and it might have been different. The ship was there and were alerted so I was only in the water for about 5 minutes.

Was there anything I would have done differently , no I don't think so. I did everything I could think of the get my engines back but once I had made the decision I followed it through. Even having 2 engines doesn't always guarantee getting there but someone was looking over my shoulder on Wednesday and I am here to have Christmas with my family.

I wish you all a very Happy Christmas and good cheer.

easy307

18th Dec 2009, 10:29

Twin Comanche ceiling is 7000 feet on 1 engine at max weight.

proplover

18th Dec 2009, 12:36

Thanks for the update ManxLadyBird - all I can say is is a heartfelt Well Done. You showed that in adverstity you had the training, the method, the equipment, devised a plan and stuck to it.
I hope you doubly enjoy you Christmas this year and I for one hope Im never in a similar position but if I am I hope I can be as calm and as well planned as you were!

dublinpilot

18th Dec 2009, 12:39

MLB,

Thank you very much for telling us your story.

The one about not being able to get into the life raft is an important one, and something we can all learn from. Having attempted to get into a life raft in a warm swimming pool, I realised that it would be impossible without steps. I was surprised to learn that our own liferaft didn't have steps, but at least learnt that it had a rope at the base of the inside wall to help pull yourself in. Had I not looked that up, I would have never known, and just assumed it had steps.

It's one that any of us carrying a life raft can learn from. Thank you for putting it into the public domain ;)

Can you tell us anything about the moment of impact? I've wondered whether I would hit my head off the panel so had that I'd be dased (or off the yoke)..afterall no airbags! Or is the deceleration less of a 'car crash' type? There isn't much information out there about such incidents, and I'm sure we can all learn some potentially life saving information from you.

Thanks so very much for telling us what you have already.

dp

ManxLadybird

18th Dec 2009, 13:44

If you remember back to your very first landing you did as a student pilot, not even a solo, but your first. You thought you were going far too fast and ooooh 'eck its gonna hurt, but you flared and the wheels touch down and all was calm.... well the first part is true and the second part isn't.

I was lucky because I had my undercarriage folded away so I had a relatively smooth underside. But you feel you are coming in far too fast, but you cannot slow down, certainly in a comanche as if you go much below 80 knots she will fall out of the sky, so you come in fast, the lower to the water you get you tend to lose a bit of elevator authority or so it felt, you feel like you want to stretch the glide but that won't work either.

At the last couple of feet you haul on the elevator and touch down tail hard so it takes all the force of the landing and bleeds the speed off. It makes a hell of a bang, and if I knew what hitting a brick wall was like I would say it was like hitting a brick wall. It was hard.

The main fuselage then belly flops on the water. You should already have opened the door and latched it open on the way down so when the frame distorts your door is already open. On the way down you have opened the door, you should then tighten your straps and put your feet on the floor. If they are on the pedals they could slip past and get trapped. What are you going to do with the pedals anyway? I also held onto the controls as a way of bracing myself.

I think because of hitting the tail hard and my bracing I prevented myself taking the full force of the ditching and therefore prevented whiplash. I had also made sure my props were feathered so the water did not catch them and help water loop me.

All my safety equipment was in easy grab reach. I told the D&D people exactly where I was ( but they knew that) and what I was going to do and they worked the rescue round me. They wanted me to glide 18 miles but I knew I had about 10 miles glide so I had to make the plan and execute it.

The other thing to remember is that your time frames all go to pot. What you think is 5 minutes could be 30 seconds or 10 minutes. I do know however that I ditched at 1223, like a good pilot I looked at my watch on landing!!

Phil Space

18th Dec 2009, 13:48

Thanks for the info MLB.

As others have asked what are we liable to expect on impact?

Did you feel you were in control throughout the situation?

How quickly did the aircraft sink.

Sorry to ask so many questions but I'd like to know what to expect if it ever happens to me.

I've done loads of trips CI to Cardiff and back over the years and I have to admit I've always felt it was a case of dying if the engine quit.

Captain Stable

18th Dec 2009, 13:55

MLB, thanks very much for that.

There is, indeed, a technique for getting into a liferaft if not equipped with steps. It's not easy at all.

Good thinking on choice of ditching area and, in insisting upon an immersion suit your husband quite possibly saved your life. Best Christmas present he could have given you (or you to him).

Congratulations on a job well handled, and enjoy Christmas! :O

Phil - time an aircraft will remain afloat depends on too many factors so one example will not give you a representative sample. For example:-
Full or empty tanks?
Hig wing or low wing?
Gear extended, retracted or fixed?
Windows damaged in impact?
What type of doors?
High or low-speed impact?
etc.If I've learned one thing in aviation over many years, it's that NO incident is ALWAYS going to be fatal - there is always hope. All you have to do is your best.

To quote Bob Newhart:-
"If we should have to ditch, how long will the plane remain afloat? Is that your question ma'am? Gee, that's awful hard to say. Some of them go down like a rock. Others, for some reason or other stay up for - ohhhh - two or three minutes."

I've known two pilots who have ditched, both in high-wing 8/10-seaters. Both floated for about 5 minutes. One was pilot only, the other was a full load. In the second case, all survived the ditching, but one died of hypothermia in the ambulance on the way to hospital. Both of those were in the Caribbean.

Dusty_B

18th Dec 2009, 14:14

I was 32 miles away, towards Lancaster, when vectored to the scene to provide top-cover. MLB was still enjoying the peace and quiet of her new glider at the time, descending through 3000', as we raced towards the scene at about 190kts. About five miles out, we could see the support vessels motoring towards eachother at speed. At 3 miles, I spotted the helicopter and, we think, a flash of orange life raft! At no point did we see AN. It had sunk without trace within a few minutes. No debris, and no fuel (which was, having confirmed MLB's safety, our new primary duty to ascertain).

It was a joy to behold the speed that everyone in the gas field reacted (or rather, by the time we were overhead - HAD reacted), and the co-ordination between aerial assets, Warton (who were relaying D&D), the field, and the local coastguard station.

My heartfelt congratulations to Kate.
:ok:

CGD406

Timothy

18th Dec 2009, 14:22

MLB,

You appear to have had what we all assume is virtually impossible, which is two simultaneous engine failures without a common cause. All the examples mentioned above have had a common cause (fuel starvation, fuel icing, bird ingress etc.)

A friend (well known about these parts, though now no longer flying) had a double engine failure on a Baron. But that was caused by having chrome cylinders on one side and not the other and during rebuild the wrong rings were put on the wrong side - resulting in all 12 ring/cylinder interfaces being wrong and therefore both engines failing. That is explicable and understandable.

I am a cynical soul and consider the chances of the two failures being completely unconnected too low to consider seriously. I therefore want to hunt for the common cause. It does seem that both sides may be CSU related (overspeed (ie too fine) on one, underspeed (ie too coarse) on the other) so that sets me wondering whether you have had any work on the CSUs or props recently? Or indeed engine work?

The reason I ask is that many of us predicate our whole twin flying lives (I have been flying MEPs for 30 years) on the premise that unrelated failures don't happen. I fly to seriously remote places, where I would almost certainly die if the aircraft came down, and I only do it because I assume that one or other will keep working. I am also very conservative about fuel planning and IPA.

So I really want to know if this really was that seemingly impossible separate cause incident, or if you can think of anything.

Thank you,

Captain Stable

18th Dec 2009, 14:55

It would be nice to see an apology to MLB from JAR FCL on this thread.

cats_five

18th Dec 2009, 14:57

<snip>
There is, indeed, a technique for getting into a liferaft if not equipped with steps. It's not easy at all.
<snip>

And I wonder if it's harder for a woman than a man, given women tend to be smaller and relatively weaker in the shoulders? I did a lot of dinghy racing in the past, which of course means I did a lot of climbing into dinghies from the water and even with a dinghy with only 4" or so of freeboard it was hard, even when I was slim and very fit.

But I suspect the liferaft would at least be much easier to spot from the air than a person in the water, and if that is the case hanging onto it is a probably good thing so long as sea conditions allow.

I'm almost certain the immersion saved MLB's life - the sea is very cold at present and survival time is measure in a handful of minutes at best. MLB's hubby is to be commended for insisting on it. Hope she never needs to use it in earnest again!

There is so much utter b:mad:ks on Pprune, but once in a while an utter gem comes along and the post from MLB is one of them.

vanHorck

18th Dec 2009, 15:12

MLB,

As the proud owner of twin GMAIK which used to live at Manx, congratulations and indeed what good advice from your husband!

We hope to hear al the details of the ditching itself, if you can being yourself to reliving these and sharing them

vanHorck

7AC

18th Dec 2009, 15:49

Mystery solved and what can I say but "Bravo" and very well done.

Saab Dastard

18th Dec 2009, 15:55

I have taken the liberty of editing the thread title to reflect the successful outcome of the episode.

Good job, glad you're safe ManxLadybird! :ok:

And thanks for sharing your experience on here.

SD

Islander2

18th Dec 2009, 16:02

Timothy said:It does seem that both sides may be CSU related (overspeed (ie too fine) on one, underspeed (ie too coarse) on the other)It is difficult to see how any CSU failure could cause the manifold pressure on an engine with the throttle well open to drop to 17". Surely that could only be caused by an induction blockage?

EddieHeli

18th Dec 2009, 16:25

It looks like both engines had low MP.
Anyone got any idea what could cause this?
and I would also be interested to know if the plane had just been in for maintenance.

Eddieheli

Captain Stable

18th Dec 2009, 16:45

Eddie, could you please explain to me how you consider that low MP can cause an uncontrollable prop overspeed?

Lister Noble

18th Dec 2009, 17:12

what a fantastic outcome for you and your family.
I just hope that if anything a fraction as risky as your problem, ever happend to me ,that I react with your courage and calmness.
It probably didn't feel all that calm at the time:)
A lady flight instructor who flies from our strip recently had a canopy smashed,possibly bird impact but not known.
She was covered in blood and could only see properly from one eye,but managed to land in a field unhurt and aircraft undamaged apart from what happened in the air.
Perhaps ladies are better at it than us chaps when the chips are down?;)
Lister

RatherBeFlying

18th Dec 2009, 17:46

MLB did very well and her husband likely saved her life by insisting on her wearing an immersion suit, especially when she was unable to board the liferaft.

Without the immersion suit she may not have remained able to hold onto the liferaft until rescue, although in this case her rescuers were exceedingly prompt:ok:

To those flying overwater: Does your liferaft have effective boarding steps?

mm_flynn

18th Dec 2009, 17:48

, could you please explain to me how you consider that low MP can cause an uncontrollable prop overspeed?

...[right engine] overspeeding in excess of 2800 rpm and I could not stabilise it. The MP was low as well so I did not have much to play with.

... my left engine lost power. My MP was down to 17 inches. would sort of suggest a low MP problem developed on both engines and an overspeed on one.

It would seem to suggest a general induction problem (snow packing, induction ice???) as both engines appear to have been affected. Is there a reasonable CSU failure mode that could have the same root cause?

--------
I am not aware of an engine failure mode that results in less than atmospheric MP other than 'induction blockage' or a 'stuck' throttle cable (indirectly causing an induction blockage)

Captain Stable

18th Dec 2009, 18:49

Anyone who has seen the construction of a CSU will know that low MP cannot cause a prop overspeed. The only thing that can cause a prop overspeed is a failure of both governors within the CSU.

As I read her post, MLB was between cloud layers and not in icing conditions. She talks about completely different symptoms for each engine failure. It is possible that the second failure was caused by intake icing descending through cloud layers, but I won't bet much on that - MLB was there - she could probably tell you whether it was likely given the conditions at the time.

As for the first engine failure, my money is on some mechanical failure within the CSU.

Robin400

18th Dec 2009, 19:02

Will cause a low MP indication, having the same effect at closing the throttle.
Selecting alternate air would provide unobstructed air supply to the engine restoring power. No info is this is catered for on this aircraft.

jayteeto

18th Dec 2009, 19:44

MLB, what have you written in your logbook for the landing point? I have an entry in mine from years ago that says take off point Belize International and landing point 'A Swamp... Ouch'.

No Foehn

18th Dec 2009, 20:03

I guess her log book may be a little damp and out of reach.

Flyingmac

19th Dec 2009, 09:36

sycamore

19th Dec 2009, 10:31

Congratulations to MLB for a successful outcome to a double emergency,and to the rescue crews for their prompt reaction.
I don`t know what the Comanche POH , but it may well be worth thinking about that in other larger pistons ,in extremely cold weather,one should cycle the props several times,maybe every 45min-1hr,to circulate fresher ,warm oil through the governors,as the viscosity would /could change ,leading to poor/ degraded control,especially in a long constant power cruise.
It is only a thought ,and no way reflects the events .

cats_five

19th Dec 2009, 11:02

As a flying diver,( or a diving flier), I can tell you that there is little difference in the sea temperature in that area between winter and summer. You will chill through very quickly any time of the year without protective clothing. Heat is leeched from the body 20 times faster in water than air. The average temperature recorded on dives is only 7Celcius.

Found a URL for surface temperatures, and whilst I agree the deeper water won't vary much at all, the surface seems to by up to 10C. But it took a lot of time & swearing to get that far with the site - it seems very slow.

Coastal Observatory, Liverpool Bay, Irish Sea (UK) | Satellite (http://cobs.pol.ac.uk/cobs/sat/)

But even if the water was at it's warmest, MLB should keep wearing her immersion suite.

19th Dec 2009, 15:20

I am a cynical soul and consider the chances of the two failures being completely unconnected too low to consider seriously.

I agree. However, the evidence is at the bottom of the sea and the AAIB are unlikely to recover it.

UV

englishal

19th Dec 2009, 15:52

Interesting read from MLB, well done.

I "ditched" 50 times in the summer - but I had floats on :)

Regarding a double engine failure in a Multi, purely for interest sake - One way which could cause a DEF on many types is to crossfeed only one engine and forget about it. If you do this, both engines feed off one tank, BUT the fuel return of the crossfed engine goes back into the tank on the side of that engine. The result is that you have a huge fuel flow from one tank (~whatever, say 30 gals/hr) with the other tank starting to fill up from the fuel retun. When full of course the excess fuel will be dumped overboard. So eventually both engines stop - as the tank they are running off is empty, but you still have full fuel in the other wing...

robbo

19th Dec 2009, 18:15

This is the second time a Comanche has ditched near to these rigs:

http://www.aaib.gov.uk/cms_resources.cfm?file=/dft_avsafety_pdf_500979.pdf

The last one was G-ASRH in 2001.

stickandrudderman

19th Dec 2009, 19:17

Congratulations to MLB for excellent handling and also for reporting to the rest of us so we might learn.
The technique for getting into a liferaft without steps involves submerging oneself by pushing against the liferaft and then using inertia from bouyancy to propell oneself into the liferaft. It's not easy in a training pool so I can only guess how hard it is for real!

KeepItStraight

19th Dec 2009, 20:09

The only thing that can cause a prop overspeed is a failure of both governors within the CSU.

Not quite true, lose of pressure (Nitrogen/air) in the prop dome will cause and over speed as well.

If you do this, both engines feed off one tank, BUT the fuel return of the crossfed engine goes back into the tank on the side of that engine.
Not in the case of engines fitted with the Bendix fuel injection system as fitted to Lycomings, of which the Comanche is one type with these engines.

Induction icing is unlikely to cause a power lose due to the location of the intake plus the Comanche is fitted with automatically opening alternate air doors which can be also opened manually.

Islander2

19th Dec 2009, 21:17

KeepItStraight said:

Induction icing is unlikely to cause a power lose due to the location of the intake plus the Comanche is fitted with automatically opening alternate air doors which can be also opened manually.You may well be right, and this could well have no bearing at all on the accident in question.

However, it is certainly interesting to note that the alternate air door design in the the PA30 is poor and has been responsible for engine failures (and, I understand, double engine failures) through air inlet blockage in the past. From an air accident report:

The original design of the alternate air door on the normally aspirated PA30's and PA39's puts the door downstream of the air filter and in an area of high vibration. A failure of the door hinge or shaft will lead to an immediate engine failure. A modification exists to move this door to a lower vibration area on the lid of the air filter. If not modified, this door should be inspected thoroughly and frequently (we have had an Australian fatality due to this).And from a separate Twin Comanche incident arising from alternate air door failure:

I was flying my PA-30 over water together with my friend Michael in his PA-39. My position was some 200 ft behind and to his right side (we flew many thousands of miles that way, with the leading aircraft calling for both as "Comanche Formation"). All of a sudden it looked like he applied brakes: His aircraft slowed down and in a second I was at his level. I throttled back and we exchanged ideas about what went wrong, as all gauges were normal. All of a sudden he started to accelerate and soon operation was normal. This repeated itself several times to our amazement. However, he was able to make it safely to destination. After landing we started to look for a possible cause and it did not take long to find that one of these doors got loose and partially blocked the air passage. When it moved back and forth the size of the free passage was changed. Fortunately, there was never a full block. Thus the lack of prop RPM stability through a wildly fluctuating manifold pressure could be explained! Of course, as I said, this could well have no bearing at all on the accident in question.

mm_flynn

20th Dec 2009, 07:28

Islander2 and I threw 'induction blockage' out as an idea to explain low MP on one (or depending on how you read MLB's post both) engine(s). There have been several answers of how common forms of intake blockage shouldn't effect this aircraft. Moving away from this particular case - are there any system failures that can result in less than atmospheric MP other than an induction blockage? (ignoring the case of a faulty gauge)? Are there any sources of inflight induction problems other than, icing/snow, broken alt air door, others??

mark147

20th Dec 2009, 16:55

Moving away from this particular case - are there any system failures that can result in less than atmospheric MP other than an induction blockage?
To see the MP reduce, I believe you must either have an increased intake restriction (e.g. throttle closure, intake blockage/icing etc.) or increased engine RPM (effectively causing increased suction from the engine and hence increased pressure difference across any existing intake restriction, intentional or otherwise).

So I can see how a failure of a CSU would show up as reduced MP as well as increased RPM. But a failure that just results in decreasing MP (and no RPM change) can't, to my mind, be caused by anything other than an intake restriction of some kind.

Mark

IO540

20th Dec 2009, 17:41

You would need a helluva RPM increase to drop MP really significantly.

On my TB20 (IO-540-C4 engine) I see about 1/3 inch MP change from 2300rpm to 2500rpm.

However, we don't know anything about ManxLadybird's flight conditions.

Islander2

20th Dec 2009, 18:32

You would need a helluva RPM increase to drop MP really significantly.True, but it's the converse that is more interesting. If it were a failed alternate air door, the MP could have been fluctuating between 17" and, say, 22" ... which, presumably, would put the prop on and off its fine pitch stops and present a fluctuating or 'unstable' RPM!

IO540

20th Dec 2009, 19:26

Yes, very much so. At the low MP end the governor would drop out of regulation, and at the top MP end it would overshoot a bit.

So a messy/intermittent intake blockage could manifest itself as wildly varying RPM.

Metars for 16/12/09 around 1200:

METAR EGNH 161250Z 32009KT 9999 -RA FEW023 SCT038 06/04 Q1011
METAR EGNH 161220Z 32008KT 9999 -RA FEW022 SCT033 06/04 Q1011
METAR EGNH 161150Z 32009KT 9999 -RA FEW022 SCT033 06/04 Q1012

For some reason can't get the skew-t from Wyoming Univ. Some from here (http://www.meteo.uni-koeln.de/meteo.php?show=En_We_We) for the general area suggest solid IMC from a low level (which the metars don't support) to c. 15000ft with 0C around 3000ft. Meteox.com shows strong scattered returns for the area.

Could it have been snowing?

Flyingmac

21st Dec 2009, 08:33

Can anyone tell me what depth of water the aircraft sank in?

icantfindagoodname

21st Dec 2009, 10:20

MLB,

Congratulations on a fantastic outcome and thank you for posting on this thread.

A lot of different emergency agencies where alerted and on standby for you - and I would just like to thank them all.

Have a great Christmas and I hope your back in the air very soon.

Oldpilot55

21st Dec 2009, 12:47

The Irish sea is not particularly deep.
http://upload.wikimedia.org/wikipedia/commons/a/a2/IrishSeaReliefMap.jpg
I would think around 20 metres or so, where the ditching occurred.

Flyingmac

21st Dec 2009, 13:42

If it's only in 20mtrs it would be fairly easy to bring it to the surface, but doubt it would be worth the effort. Easy dive though.

Captain Stable

22nd Dec 2009, 09:16

Easy dive though.I think not. Poor visibility, strong current, BLOODY FREEZING :eek: even in a drysuit, and a relatively very small thing to find as well as quite light so it could have drifted for quite a distance. The expense of mounting a dive to locate it would far exceed the replacement value of the airframe.

englishal

22nd Dec 2009, 10:40

Perhaps there is an ROV vessel in the area already due to the oil and gas ops which can salvage it? Not cheap of course but it depends if it has to be salvaged for any reason....

rocco16

22nd Dec 2009, 13:06

Quote:
Easy dive though.
I think not. Poor visibility, strong current, BLOODY FREEZING http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/eek.gif even in a drysuit, and a relatively very small thing to find as well as quite light so it could have drifted for quite a distance. The expense of mounting a dive to locate it would far exceed the replacement value of the airframe.

Not difficult to dive on the slack although vis may be an issue. Site would need to surveyed by decent side scan sonar to locate and/or a form of magnetic detector. Not sure it would be worthwhile going to the effort.

mm_flynn

22nd Dec 2009, 16:10

Neither insurance nor the AAIB appears to have pulled out the previous Twin Comanche that went down in the area. The salvage value of the airframe will be pretty much nil (how much for a light twin with no engines or avionics ??)

The AAIB report will probably be a factual description of the events of the flight, ending with The pilot was unharmed but was later flown to a mainland hospital as a precaution.
Further investigation as to the cause of the total power loss could not be carried out as the wreckage was not recovered from the sea. (From the AAIB report of 8 years ago - same type, same place).

Flyingmac

22nd Dec 2009, 18:19

Had vis of 20mtrs plus in UK waters at 60mtrs depth. Cold not an issue if properly equipped. Current is rarely a problem at slack on a neap tide. Sidescan sonar much cheaper these days and very good when used with GPS. Our RHIB can run a search pattern at 40 knots. Still not worth it though. Price of Aluminium too low. Fuel too high. Won't bother.

BEagle

23rd Dec 2009, 14:38

ManxLadybird, my warmest congratulations on an excellent piece of flying. Whilst the cause of the double engine failure is a mystery still, the description you provided of your descent and pre-ditching drills was quite outstanding. Were you taught all those things you described, or was it instinct? Either way, that was a 'copybook' ditching.

I'm sending you a PM as I think that your account needs a wider audience - many of us have already learned a lot from your post and I thank you for that!

Congratulations again; enjoy a relaxing Christmas!

herman the crab

23rd Dec 2009, 20:25

40 kts? How do you stop the 'fish' from coming out of the water at that speed? And I would think the data is unusable too - we struggle much above 4 or 5 kts to get quality usuable data.

HTC

Flyingmac

24th Dec 2009, 09:24

Fairly flat sea bed. Find target at decent speed with a good sounder and mark with M.O.B button on GPS. Positively ID target with slow speed sidescan pass. Job's a good'un.

Tropical John

25th Dec 2009, 08:00

Perhaps there is an ROV vessel in the area already due to the oil and gas ops which can salvage it? Not cheap of course but it depends if it has to be salvaged for any reason....

There is! It is the Northern Canyon, on contract to Centrica. Operator Hallin Marine ( www.hallinmarine.com (http://www.hallinmarine.com) ). Vessel has both ROVs and diving spread onboard. Operating in Morecombe Bay area now until approx beginning of February 2010.

Operating cost per day of the Northern Canyon > Hull value of of a PA30 so unlikely to be worthwhile. I need to declare personal interest - but happy to help if someone wants it back :)

herman the crab

26th Dec 2009, 19:35

Well your RIB must have some pretty fancy equipment on board as I've not come across an echo sounder that gives usuable data at that speed in a RIB either!

HTC

AC-DC

26th Dec 2009, 20:01

Quote:
The only thing that can cause a prop overspeed is a failure of both governors within the CSU.

Not quite true, lose of pressure (Nitrogen/air) in the prop dome will cause and over speed as well

But if you lose the pressure in the dom the prop. is out of control and you can't feather the prop.

easy307

28th Dec 2009, 10:12

Big Blue Scuba Divers in Port Vila,Vanuatu have recently sunk a twin engine Pipe Comanche Twin engine aircraft for recreational divers to enjoy while also creating an artificial reef for marine life to enjoy!

YouTube - Big Blue Vanuatu (http://www.youtube.com/watch?v=XCH8LpWqSH8)

robbo

14th May 2010, 17:35

Aircraft recovered:

BBC News - Crashed plane recovered from seabed (http://news.bbc.co.uk/1/hi/world/europe/isle_of_man/8681248.stm)

KeepItStraight

15th May 2010, 04:33

Six months is a long while between ditching and recovery plus there is likely to be quite a bit of recovery damage, it will be very interesting to see what is found wrong with the aircraft.

robbo

20th Oct 2010, 12:37

AAIB bulletin report:

Air Accidents Investigation: Piper PA 30, M-ALAN (http://www.aaib.gov.uk/publications/bulletins/october_2010/piper_pa_30__m_alan.cfm)

IO540

20th Oct 2010, 13:09

How can one have an uncontrollable overspeed condition if the throttle and mixture are both working and the engine power generation can be totally shut off?

mm_flynn

20th Oct 2010, 19:21

How can one have an uncontrollable overspeed condition if the throttle and mixture are both working and the engine power generation can be totally shut off?
My understanding is one must slow the aircraft down to the point where the RPM on the fine stops is within the target range in governor failure modes such as described. There is no indication in the narrative this was attempted.

IO540

20th Oct 2010, 20:04

If there is enough airflow (speed) to overspeed a prop which is against its fine pitch stop, with the throttle shut, then surely shutting down that engine is not going to make much of an additional improvement.

As you say, one needs to slow down a bit.

AndiKunzi

5th Jan 2016, 08:06

Easy to judge from the couch and not being in danger:
vyse and zero thrust on the engine will keep the prop well below max. RPM when the propeller is at it's most fine position with no pressure against oil pressure.
Some reduced positive thrust will be possible at blue line with max. RPM.

Shutting down the engine doesn't help at all, because the propeller continues windmilling. You can't feather a runaway prop unless cutting oil pressure and having left some opposing pressure (nitrogen or spring). Windmilling engine creates its own oil pressure.

Even a very lightly loaded TwinCo will hardly hold 3000 ft with a windmilling prop.

These thoughts are no judgements for the decissions on this flight, but should help others in a similar case.

Regards and safe flying,
Andi