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Hi Mike,
Do you pre-flight your airplane each time before you fly? Do you have
SOME system to confirm that what your fuel gauge says is accurate
before take-off (e.g. dip stick, full, or even "educated eyeball")?
And, can you reliably tell when fuel transfer is not working?
If you answer "Yes" to the above, then I would submit that you are
starting each flight with a known quantity of fuel and have a reliable
system for determining if there is a problem requiring you to land
early. I applaud any such a solution.
If any of those answers are "no," then you have an opportunity to
improve your process. Perhaps the risk is "low," but why take it if a
better way takes only seconds?
My biggest concern on these forums is that there are folks who have
been doing things for decades in a way which works "most of the time"
and they've "never had a problem." By posting "advice" that is either
incomplete (leaves out an important confirmation step) or is actually
they way they do things and leaves out important confirmation, it is
possible to leave younger pilots with ideas that can end them up in
needless trouble.
There are often many "right" ways to do things. The criteria for
determining a "right" way is simple: does it insure that you KNOW the
condition of your plan before you fly so that you are making planning
decisions based on facts rather than assumptions.
I had one fellow reply privately to me that he never performs
pre-flights. Rather, he post-flights before putting his plane in his
hanger after fueling and is the only person who flies the plane. This
is the sort of solution that works "most of the time" and "sounds
reasonable." However, life isn't reasonable. Things break. Fuel can
leak out on the hanger floor, evaporate, and leave no sign. A slowly
leaking tire can cause a deadly accident if not checked before flying,
rather than after. Etc.
In a recent thread, I avoided being critical of people's personal
choices - saying only that choosing to fly faster than Vne is a "risk"
and noting that apparently no one in a 320/360 has died from this alone
(leaving out the T-storms). I am absolutely fine with people taking
risks with their own lives that they know that they are taking - it is
THEIR life. I am not so good with people taking risks on behalf of
others (passengers, people to whom they give advice) who may be
trusting them to exercise superior judgment, and when I think I see
such behavior I tend to speak up.
So to everyone out here - I would ask that you please consider the
impact of your "suggestions" on these forums. If you knowingly take
risks, then please either don't recommend that technique or make it
clear that you know there is a possibility that your system could
"fail" at an inopportune time but that you personally find the risk
acceptable.
Happy New Years All!
Bill Reister
mikeeasley wrote:
I'll give you the "known quantity"
definition. But just because the fuel is in your wing doesn't mean you
are 100% sure it's available to burn, right?
And a properly functioning,
accurately calibrated capacitance probe and digital gage is
significantly more accurate than the GA standard fuel gages I had in my
201.
A couple things I do to confirm the
functionality of my fuel gages is to do the math between the fuel flow
reading, fuel tank levels, and how much fuel it takes to fill the tanks
when I'm at the pump. Those little mental math exercises give me a
reality check on a regular basis. For example:
If I switch tanks in an hour, my
left tank should be down to 30 gallons by then...
If I switch tanks now, I should land
with about 22 gallons in each tank...
It should take about 35 gallons to
fill the left tank and 30 gallons to fill the right tank...
I completely lost my JPI EDM 900 a
few years back, just went black about an hour into a flight. I landed
and got it repaired before flying home. I knew I had a bunch of fuel
on board and how long I'd been flying on the current tank because I
keep good ol' tank switching notes on my flight plan sheet on my lap
board. And I do visually check the fuel quantity in my tanks during my
preflight, although I can't really tell very accurately how much I have
unless the tanks are pretty full.
Maybe a paint stick with some
Sharpie marks might be a good thing to have for partially fueled
flights.
Mike Easley
Colorado Springs
I received two responses to my post; I am responding to
both in this post.
To both Grayhawk and Mike Easley I respectfully submit that you are
asking for needless trouble.
If you will refer to my original post, I did not say that "Full" was
not the only POSSIBLE "known quantity, but rather that it was the only
known quantity for each tank on most Lancairs. That is a FACTUAL
statement, your arguments about the reliability of your respective fuel
gauges notwithstanding.
Do you visually confirm that the amount of fuel in each tank matches
what the gauge says, and if so, how? Capacitance gauges, while very
accurate today, do have failure modes. Do you know all of them? Do
you know how to recognize them in the cockpit? Is it even POSSIBLE to
recognize them all in the cockpit?
Fuel starvation is one of the leading causes of accidents and is THE
most preventable accident cause.
The same type of gauges were used in the F-4 Phantoms I flew in my
mis-spent youth. One day on a training flight after the external tanks
were dry, I started noticing that my fuel quantity seemed to be going
down more quickly than Lead's. Too, the gauge was "bouncing around
more than normal." After a brief discussion with my back seater we
decided we would rather be live sissies than end up walking home or
worse, so we told Lead we were heading home. Lead, being a rather
arrogant ass, asked us to repeat the diagnosis we had already performed
and, in level flight, the gauge seemed to level out just a bit below
Lead's reading. Logically, if we both started out with full tanks and
there was no leakage, our fuel remaining should be about the same.
Lead passed off the fluctuation as a simple gauge problem and said,
"let's continue the mission and just keep an eye on it;" however, I
told him to take the stick if he wanted to fly my airplane, otherwise
we were going home with or without him. He grudgingly "led us back."
On the way home, the gauge started falling at an increased pace, so
much so that we had Lead drop back twice and look for fuel leaking.
None. On short initial the Fuel Low Level light (which was independent
from the gauge system) came on - this system was supposed to be "fool
proof" and "absolutely reliable" and was supposed to indicate 2200-2300
pounds of fuel remaining (a good 10-12 minutes at reduced power
setting). I pitched, throttled back, dropped gear and flaps, turned
base, and landed in minimum time with minimum use of throttle. On
touchdown I shut down one engine (standard practice); rolled to the end
of the runway, turned off and pulled into my hanger (by happenstance
the first hanger) all without touching the throttles again and then
wrote up the plane for a faulty fuel gauge system.
In order to inspect the fuel system gauges, it was necessary to remove
the remaining fuel from the aircraft. Full internal fuel on the F-4
was about 12,500 lbs, or about 1900 gallons which represents a bit over
an hour of flying time (~180 gallons = 6 minutes; 18 gallons = 0.6
minutes). When they defueled the aircraft, they only got 6 gallons, or
less than 20 seconds of fuel remaining.
Complacency is the single biggest killer in aircraft accidents. If you
trust your newfangled gadgets without verifying, you are an accident
statistic waiting to happen - period, and I make no apology for that
statement.
Now, having said that there ARE legitimate ways to insure there is a
"KNOWN QUANTITY" of fuel. My particular Lancair has a header tank, so
I can fill that and know I have enough fuel to ferry the aircraft to
another airport for cheaper gas. I can (and have) fill a single wing
tank, and accept that it will be wing-heavy on takeoff (I lost a gas
cap on a cross country, and flew with two tanks rather than be stuck
out for a day or more). For those builders who plan ahead ( or a
clever person improvising after instruction), tabs can be installed
inside t
he wing fill caps ala' Piper, so that if you "fill to the tabs" you
have both a balanced and known quantity of fuel. Some people have
carefully calibrated dip sticks to determine exactly how much fuel is
in a given tank.
All of these are acceptable and reliable practices. However, if you
choose to steadfastly maintain that looking at your gauge is a
"reliable way to determine your fuel" then all I can say is that when
the day comes that I see "fuel starvation" as the cause of your
accident, I will tell everyone at your funeral that you were provided
with information that could have prevented it and that you knowingly
chose to act in a dangerous fashion. Oh, and I'll nominate you for a
Darwin Award, too... ;-)
Best regards all, Happy New Year, and fly safe!
Bill Reister
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