Liferafts - spontaneous inflation?

[Hazwaa]

We are just debating the merits of putting a life raft in the front cabin of our BK117. Whilst it is a nice idea to have one available to the flight crew as well as the crew in the back it does raise the issue of a potentially catastrophic inflation in the cockpit area. The life raft type we have would be very difficult to inflate accidentally and we can position it to further minimise any risk of the deployment tab being inadvertently pulled however there is still the possibility of spontaneous inflation to consider - have any learned rotorheads out there heard of incidences of spontaneous life raft inflation? I have spent a day or so searching for cases but haven't been able to turn anything up (except for on a ship out of Hong Kong or during the Korean war).

[Sir Korsky]

Another reason to have a decent blade or seatbelt cutter within arms reach. Just remember at some airports the TSA may confiscate it when trying to take it back on the ramp

[Hazwaa]

That's a good point Sir Korsky, although I'm not sure if you'd get the chance to actually get a hold of a knife and use it effectively especially whilst trying not to crash.

[African Eagle]

Across the African continent over many centuries there has been a phenomena known as Spontaneous Human Combustion (basically when a person just suddenly ignites).

So apparently frequent were these episodes (at one point) and so widespread, that they became an accepted part of African culture. It is a phenomena which is believed by many tribes to be the result of supernatural witchcraft!

Trouble is, whenever this sort of thing happens there is never a scientific team on hand to verify what's going on and so we still don't know enough about it.

Carried a 5 man raft in the footrest area of a Bell 206 (dual pedals obviously removed) for a number of years flying off the African coast and never had an incident.

I heard that when Mercedes did their branded version on one of the Eurocopter models that they were talking about caibin and cockpit airbags but, I also heard they had an Irishman leading their design team at the time.

Hope this helps.

[mickjoebill]

One solution is to configure its stowage so that if it does inflate it comes into contact with a carefully designed sharp edge, bolted into the cabin, that punctures it.

I guess it would need to be a large hole to reduce the time it takes to deflate.



mickjoebill

[bigglesbutler]

The Bristow Tiger (AS332L) had a cabin mounted liferaft for 30 years in all types of environment without any issues that I know of. Flying everywhere from Australia to the North sea, so presumably provided it is properly serviced properly, mounted and protected it should be OK. Also don't forget you get what you pay for, pay peanuts you will get a POS that may cause problems, pay a sensible price and do some market research and you should be a serviceable solution.

SI

[Oldlae]

Bristow 206's flying offshore had the liferaft mounted on a wooden platform in the co-pilot's foot well, controls removed of course. I never heard of a liferaft opening by itself, and I saw most of the in-flight reports from all types in Bristow for several years.

[Anthony Supplebottom]

There is only one way for Hazwaa to resolve this. He must buy 10 life rafts, stick them in the proposed storage location, tie a piece of string to the inflation chord and inflate them inside his BK during repeated ground tests with the raft in different positions.

Following on from African Eagle's mention of air bags, Hazwaa should be grateful that his life raft won't inflate as rapidly as an air bag!

[John Eacott]

Originally Posted by Hazwaa

We are just debating the merits of putting a life raft in the front cabin of our BK117.

Hazwaa,

I used to carry a smaller 4 man raft in my BK117 between the pilot's seat and the door, with the lanyard secured to the seat base and a sharp blade readily accessible.

To operate the raft when required just jettison the door to let the raft out, not a problem

[industry insider]

Bristow S-76A series, S-61s, and as has been mentioned 332Ls all had life rafts in the cabin since Bristow started flying offshore. The S-76 life raft was between the pilot and the door with one on the back seat or latterly, under the middle row of seats. Externally fitted rafts have only been in for around 10 years.

[skadi]

The Lynx f. example is fitted with personal liferafts as seatcushion, could also be used as ejection seat
Anybody heard from spontaneous inflation?

skadi

[S76Heavy]

not quite the same, but..

The only spontaneous inflation I have ever witnessed in a helicopter was the time a particularly unsociable pilot farted in his survival suit; one cannot regulate against this but that is the time I wish I had had a knife handy. I'm sure the judge would have passed a lenient sentence.

In almost 20 years of offshore flying I have never heard or witnessed any life raft inflate spontaneously, while I have heard of rafts failing to inflate.
So while it is prudent not to locate it close to your flying controls and take precautions, a well maintained and well designed life raft should not be a problem.
However, think about how you will deploy it if it ever comes to the point that you need it. I have seen rafts in places that would be impossible to actually use them in case of a ditching.Then there is no point in carrying them other than the tick in the box.

[Ascend Charlie]

I recall reading of a case in an old USAF jet trainer (tandem, maybe a Thunderchief? T-33?) where the back seater was trying to get more comfortable by wriggling on the ejection seat. He set off his 1-man life raft under his seat cushion.
It expanded rapidly, and started pushing on the control column, felt by the pilot in the front seat, who then had a hard time holding it against an increasing pressure. He also heard the muffled groans and grunts from the backseater as he was squashed up against the canopy. The backseater grabs his survival knife and stabs the dinghy, resulting in a loud BANG, a cloud of talcum powder, and the control column suddenly going slack.

Stuff this, thinks the front seater, and he ejects.

Oops, thinks the back seater, and also ejected. Don't know how successful it was with a tattered dinghy interfering with the ejection seat, but it makes a good story.

[tistisnot]

Myth busters required for sure for some here ......... surely we cannot believe this?

Have you ever heard of a life-jacket spontaneous inflation - no. It is the same mechanical system of inflating the life-raft - protective gas bottle to hold under pressure and a trigger mechanism ..... release trigger, gas escapes, desired effect ..... yes, for sure inadvertent inflation - pulling of chord attached to trigger (caught in clothing, foot caught in loose chord) which removes trigger to release gas.

And as for the spontaneous human combustion ..... no-one ever went flash and burst into flames ...... a body was found later which seemed to have burned ..... unconscious, drunk, dead with flame source close by which burned body wax just like a candle .......

Next youŽll be telling me that telephone signals interfere with avionics / instruments .....

[rotorfossil]

Inadvertent inflations certainly have happened in the RAF in years past causing some fatals, which is why flying suits had a knife sewn to the suit.

[technoprat]

I've heard of 2 spontaneous inflations.
Both in the Middle East, both on B412.
1st was mounted in the pax cabin next to the 1/4 door, it inflated in flight, quite slowly, but still caused problems for the pax. That company now carries a small cerated knife mounted on the center console near the collective head.
2nd was skid gear mounted & went of on the ramp.

[maeroda]

Flown 12 years on 412 with an EAM 9 in the pax cabin; never had any spontaneous inflation as long as pax hands stood away of inflation lanyard.

Question: if we talk about spontaneous life raft inflation why not mention spontaneous life preserver inflation?????