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Scot Stambaugh wrote: If you have an engine failure isn't it true that you
no longer have cabin
pressurization...
Scot, you'll definitely lose cabin pressurization rapidly with an engine
failure. You can also lose it with a significant power reduction at
altitude, although there are some other adverse effects, such as shock
cooling, that you'll want to consider even during an emergency
descent...unless the reason for your descent is that the engine has already
decided to "cool itself."
I'm not an instructor (any more), but the basic rules still apply: 1) Fly
the airplane. It will fly a very long distance, and for considerable time
with no engine if you start down from the flight levels, so establish and
trim to your best glide speed first.
I'd probably get the oxygen mask on and verify the flow of O2 next, but if
you're not really high and the ground is close (flying over the mountains?),
you might want to turn toward a suitable landing area before working the
emergency oxygen. Even at FL 250, you should have a couple of minutes of
"useful consciousness;" more if lower. Not something to fool around with at
all, but there are legitimate alternative actions after step #1. BTW, IMHO,
anyone who flies these machines in the flight levels should be required to
go through one of the excellent US military altitude chamber orientations.
I've heard it is a bit difficult to arrange/schedule if you don't have
direct access to a military base, but the hassle is well worth the effort!
One thing the available flight time will give you is the chance to
communicate. Good assistance is readily available, from a heading to a
suitable landing site to advice about the weather conditions below, to
knowledge by a responsible person on the ground that you're in trouble. When
you get the above things sorted out, this one comes up next in my
priorities.
Unless you're seeing pieces of the engine sticking up through the cowling,
next is probably a restart attempt. There are a number of malfunctions of
these turbo'd engines that can be at least partially "corrected" after you
come down a bit. I think Don Goetz blew a hose off the (pressurized) intake
runner of the factory IV-P some years ago that got his immediate attention,
but he was eventually able to restart and land "normally." Restart is
certainly worth a try until the time that it detracts you from setting up
for a successful landing.
As to landing in this situation, one that you walk away from is certainly
successful by anyone's measure of merit. Having looked at six "crashed"
Lancair IV/IV-Ps over the past 8 years, I'm absolutely convinced that IF you
can keep the pointy end from impacting the ground at a high angle, you and
your passengers can walk away. We are building and flying an incredibly
tough and "impact energy absorbing" airplane. It will easily crush to absorb
the relatively large amount of kinetic energy that results from it's high
"landing" speed during a controlled-crash landing. "Controlled" is the
operative word here. I readily admit plagarization from several past
contributors to this column in also concluding that unless you can land and
stop on a hard surface (e.g. road or runway), I'd recommend you plan to
leave the gear up if/when this happens. If the airplane is slowed to minimum
flying speed and set down in controlled flight, you only have to avoid
hitting vertical obstructions, such as large trees, head on. If you want to
see what can be "controlled" by a fellow keeping his wits during a crash,
read about and look at the pictures of Ron Brice's recent accident...
If you're flying one of these beauties, hope you've already thought through
this scenario and either agree or disagree...it's probably too late to ask
about "time of useful consciousness" when the engine quits...
Bob Pastusek
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