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MIke,
Very well said.
I could not agree more...
Randy Snarr
"Flight by machines heavier than air is unpractical and insignificant, if not utterly impossible"
-Simon Newcomb, 1902
--- On Tue, 1/11/11, MikeEasley@aol.com <MikeEasley@aol.com> wrote:
From: MikeEasley@aol.com <MikeEasley@aol.com>
Subject: [LML] Re: post crash fire control
To: lml@lancaironline.net
Date: Tuesday, January 11, 2011, 8:20 AM
Randy,
To expand on what you said about surviving an off airport landing, it
probably makes good sense to spend one's time on efforts to minimize the chances
of having to make an off airport landing in the first place, instead of
designing a more survivable aircraft. Pilots that maintain their own
airplanes have the potential to cut corners on maintenance and increase the risk
of engine failure. Recurrent training once a year with a qualified
instructor would contribute to engine failure survivability far more than fuel
dumping in my opinion.
We've all read the reports of crashes caused by poor maintenance and lack
of recurrent training. Jeff might be able to expand on the statistics, but
the vast majority of Lancairs that have had engine failure that resulted in
serious injury or death can be traced back to design, maintenance and/or pilot
proficiency.
Just my two cents.
Mike Easley
Colorado Springs
In a message dated 1/11/2011 5:38:05 A.M. Mountain Standard Time,
randylsnarr@yahoo.com writes:
One more opinion,
If you look at most of the crashes,
that occur there is little time to worry about how much fuel is in the
tanks. I believe ones attention is best spent getting the airplane down
and managing the situation especially when flying a slippery high
performance airplane. We already have too many distractions..
I hate
the thought of landing with lots of fuel, but the prospects for getting
it out of the airplane are impractical..
Randy
Snarr
N694RS
"Flight by
machines heavier than air is unpractical and insignificant, if not
utterly impossible"
-Simon Newcomb,
1902
--- On Mon, 1/10/11, rehbinc@aol.com
<rehbinc@aol.com> wrote:
From:
rehbinc@aol.com <rehbinc@aol.com>
Subject: [LML] Re: post
crash fire control
To: lml@lancaironline.net
Date: Monday,
January 10, 2011, 12:10 PM
Kevin,
While I know that some (many?) commercial aircraft have dump
capabillity, I don't know just how they go about it.
I don't have any experience with the valve you reference. From
the picture, it doesn't look inherently leak tight but maybe it is. It
also isn't clear how you would install it, especially in series for
redundancy.
If you want to add such a capabillity to your aircraft, you need
to carefully consider the added failure modes the modification brings.
Just remember that adding another engine statistically makes
you less safe. If I were going to do this, I would have double valves
at each drain with a way to test both leak tightness and valve
operation independently at regular intervals. Obviosly, you also want
a pretty fail safe way to ensure that you don't accidently dump the
fuel, either in the air or on the ground. Consider what happens if
only one wings emties when you pull the actuating lever.
I'm not saying this is a bad idea, just that you want to think it
out thouroughly before implimenting it. As I said earlier, if I was in
a situation where the tank was likely to be ruptured, I would prefer
to have as little fuel as possible in the tanks as possible.
Rob
Rob
-----Original
Message----- From: Kevin Stallard <Kevin@arilabs.net> To:
lml@lancaironline.net Sent: Mon, Jan 3, 2011 8:35 am Subject:
[LML] Re: post crash fire control
Are you
putting in a lavatory in your Legacy?
I have been
thinking about this for some time and am glad the occasion has come up
to discuss it.
I am building a
Legacy and was trying to figure out how to incorporate a dump valve
into each wing to dump the fuel for certain cases of emergency
landings or imminent crash.
So far I came up
with this valve:
they offer it
with a stainless steel paddle in 2" & 3", one could be mounted at
the bottom of each wing at the lowest spot to dump the
fuel.
I haven't really
done much research into wether or not the aviation industry offers
such a valve, or the compatibility of the materials with the fuel or
the reliability or temperature and pressure limits, or how air will
get into the tank to replace the fuel, but it seams like the logical
general direction?
Of course, one
fear would be inadvertent dumping of the fuel or
leaks.
On Dec 31, 2010,
at 1:10 AM, REHBINC wrote:
I am a
forensic engineer and work quite a bit with fire and explosion as well
as mechanical/structural failure.
If I had a
way to drain the fuel before crashing, I would get the tanks as dry as
possible. A couple ounces of gasoline trapped somewhere in the tank
would be plenty to make the space fuel rich. It isn't realistic to
expect the entire tank to be fuel rich before impact, but a portion of
it certainly will be. It is all a matter of time and temperature. In
tank ships, you need around 2 gallons or so to make the space
fuel rich. Frequently there is more than this trapped behind the tank
scale.
For the
reasons stated earlier, I wouldn't be too concerned about an explosion
risk of the wing tanks (At least as long as I wasn't standing on it at
the time!). My biggest concern would be the size of the fuel puddle
the plane came to rest in. A hundred gallons spread out on the
runway could make a real big fire real fast and would be
difficult to survive if you were caught in the middle. Two cups of gas
in the same scenario would be a much more survivable
situation.
Another
benefit of draining the tanks before impact is the reduction in gross
weight and therefore stall/impact speed.
Rob,
interesting info.
So sounds
like if you do have a quick drain, you don't want to completely
empty it.
I have no
idea how to build a quick drain that would not create some leakage
risk.
sounds
like you are in this business?
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