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roadrabbit
4th Aug 2016, 15:16
In the event of a piston engine fire on the ground a checklist instructs the pilot, having put the mixture control(s) to CUT-OFF, to continue to crank the affected engine.

I realise the idea is to drain the engine of all fuel to the fire, but how long is a recommended time to crank?

In the event of such a fire 10 seconds would seem reasonable (watch your whole life pass before your eyes!), but what do others think?

NutLoose
4th Aug 2016, 15:36
It is also to draw the fire into the engine ie the burning fuel.


http://www.thisaviationlife.com/starting-piston-airplane/



..

Lonewolf_50
4th Aug 2016, 15:41
This looks like a tech log question, unless you are thinking through an engine fire for a car. Do you want to post it in the tech log forum?

Loose rivets
4th Aug 2016, 15:43
Oh, Woosie! Leave the fuel going in, get airborne and blow it out with the slipstream.

( you may have to silde-slip a bit if the flames lick around the cockpit.)


If you were on Tech Log I might say, passengers out - head away from the prop and upwind. Watch out for fire vehicles. Crank for ten seconds. If strong enough, turn the nose down wind. Then crank for a few more tires.

You do have gloves and even a mini fire blanket, don't you? Gloves are 100% essential kit IMHO.

VP959
4th Aug 2016, 21:23
You do have gloves and even a mini fire blanket, don't you? Gloves are 100% essential kit IMHO.

Too right!

When I stopped mil flying and switched to civil stuff the thing that really got to me was that very few people bothered to wear any form of fire-resistant clothing and I can't ever recall seeing anyone wearing gloves, except people like me or the aero guys.

I really didn't care about the snide comments I got about me always wearing kid leather gloves and a Proban flying suit, as I always considered that having a modicum of fire protection was absolutely essential, very especially when flying home-built aeroplanes.

So, aside from the basic question on sucking flames through an engine that's on fire, think long and hard about what you're wearing. Once you've seen the effect of burning synthetic fabrics on flesh you will be absolutely convinced that wearing either fire-resistant, or at the least cotton or natural fibre, clothing is a small price to pay for staying both safer and more comfortable (and my view is that a comfortable pilot is likely to be a better pilot).

radeng
5th Aug 2016, 01:01
Wool is pretty good for fire resistance. Old fashioned woollen long johns?

ExSp33db1rd
5th Aug 2016, 01:38
When I stopped mil flying and switched to civil stuff the thing that really got to me was that very few people bothered to wear any form of fire-resistant clothing and I can't ever recall seeing anyone wearing gloves, except people like me or the aero guys.


We had a Flt. Eng. (ahhhh!) who wore White cotton gloves when he flew on 4 eng. piston powered propellor aircraft. A captain once asked him why ? Well, was the reply, with 12 control levers to choose from (throttle, mixture, pitch ) and you, me, and the co-pilot, when we have an engine failure on take-off and you order an engine shut-down, I want to know which bloody hands are mine.

NutLoose
5th Aug 2016, 03:16
So, aside from the basic question on sucking flames through an engine that's on fire, think long and hard about what you're wearing. Once you've seen the effect of burning synthetic fabrics on flesh you will be absolutely convinced that wearing either fire-resistant, or at the least cotton or natural fibre, clothing is a small price to pay for staying both safer and more comfortable (and my view is that a comfortable pilot is likely to be a better pilot).

VP959 is offline Report Post


I always put on a cotton jacket when filling my car, even if it is roasting hot and I get funny looks, I wince at those wearing a tshirt when doing it.

Loose rivets
5th Aug 2016, 12:27
Then crank for a few more tires.

Anyone know what I meant? :p

mickjoebill
6th Aug 2016, 02:25
Re fire proof kit, next time you need thermal underwear for winter sports, consider buying nomex from a motorsports supplier.
They may be more expensive but they are durable, kit I bought 20 years ago is in perfect condition.
They are made in heavy and lighter grades.
If you work in hot countries at least consider nomex briefs and nomex long socks, the more skin you can protect the better.
Another tip if you wear a flight helmet is a nomex neck warmer that can be pulled up to cover mouth and nose.

The rule of thumb for burns is you add the percentage of skin burns with your age.
The closer that number is to 100 the less likely you are to survive. A score of 100 is usually fatal.
So a otherwise healthy 50 year old will perish with 50% burns.

The "Rule of Nine's" is used as an aide memoire
Head = 9%
Chest (front) = 9%
Abdomen (front) = 9%
Upper/mid/low back and buttocks = 18%
Each arm = 9%
Each palm = 1%
Groin = 1%
Each leg = 18% total (front = 9%, back = 9%)

Mickjoebill

netstruggler
9th Aug 2016, 12:54
The "Rule of Nine's" is used as an aide memoire
Head = 9%
Chest (front) = 9%
Abdomen (front) = 9%
Upper/mid/low back and buttocks = 18%
Each arm = 9%
Each palm = 1%
Groin = 1%
Each leg = 18% total (front = 9%, back = 9%)

Mickjoebill


That makes 102%.

The version that I was taught was the same, but without the palms.

... and of course the degree of the burn matters too.

Fareastdriver
9th Aug 2016, 16:51
I always wore gloves when I flew. One was marked Port and the other Starboard.

clareprop
10th Aug 2016, 09:23
I always wore gloves when I flew. One was marked Port and the other Starboard.
Excellent tip, definitely a time saver in a busy cockpit.

VP959
10th Aug 2016, 11:20
. . and if you dye one red and t'other green that really winds the pax up :E
I "acquired" a couple of spare pairs of white ones (why did they change from olive drab to white?) and they looked pretty silly, but I dyed them black, with some shoe dye, and that stopped them standing out for what they were. It also hid the dirt and oil..............

The same goes for my old coveralls. They were dyed dark blue and their origin was less obvious, as I removed all the velcro patches except the name badge one (I bought a new name badge with just my name and blood group on it). As far as I could find out, dyeing Proban doesn't alter the fire resistant properties, but even if it did I reckon a coverall that's basically cotton would give better protection than most ordinary clothing.

As for the knife, I kept that. I always thought that the idea of being able to cut a stuck harness free was a good one, and that knife was specifically shaped to do that.

Fareastdriver
10th Aug 2016, 11:56
I thought that a dinghy knife, for that is what it was called, was shaped that way to avoid puncturing your dinghy.

VP959
10th Aug 2016, 12:38
I thought that a dinghy knife, for that is what it was called, was shaped that way to avoid puncturing your dinghy.
You might be right, as I seem to remember the first one I was issued with had a blunt end. However, the one I have now has a thin, curved, blade, like a small scimitar, with a point on the end.

I was told that it was designed to hook under a harness and cut it. IIRC, the time that it was issued was around the same time that we started seeing a fair few "two strap hang-ups" in the Lynx module in the dunker.

Never happened to me (I took heed of the advice to always hold the QRB lever hard over until all the straps were out), but I remember seeing two unfortunates both have the same harness problem after an inverted escape attempt, and having to wait, hanging upside down half out of the door each side (with the thing winched up out of the water) whilst someone rushed around to find a camera and get some photos...............

Pontius Navigator
10th Aug 2016, 19:42
why did they change from olive drab to white?
So that pilots could see where their hands were.

*or that ground crew etc could see them waving.