Yes, I knew the problem was an attempted RTLS following engine out. I
was taught that if the engine failed below 4000AGL on climbout, I had to
pick my spot from what was visible through the windscreen -- the plane
was too heavy, too low and had no energy for a turn back to the runway.
Keith
Hi Keith,
what were you flying, F4s? Maybe you mean 400 ft agl :)
That is a good thumb rule about the windscreen.
I enjoy your contributions,
BR, Dave McC
Nope, I mean 4000AGL. Look over all of the RTLS attempts that end in
crashes and you'll agree.
The problem is different during climbout than during normal flight.
You're as heavy as the plane will be during the whole flight, you're at
a bad AOA, you're at a lower airspeed and your plane has a fraction of
the energy it has at cruise, and you want to make a downwind turn. If
you have a variable-pitch prop, it's in exactly the worst configuration
for flying with no power. It gets worse when you dump the gear, and
you'd better do that early, because it may take much longer than you're
used to (running on battery or on whatever pressure is left in your
hydraulics, or -- worse -- madly working the wobble pump).
Then consider that a 180 will NOT take you back to the runway. You have
to make TWO downwind turns, one to get turned around and heading for the
runway centerline then another to turn to the actual runway heading.
You are also going to be checking fuel selector and levels, trying the
ignition switch, communicating with the tower, working the gear,
quieting hysterical passengers (even if you're solo) . . .
All of these things are snakes, latching on and dragging you into the
ground much faster than you expected. You are too likely to learn the
REAL Four Basics of Powered Flight: Stall, Spin, Crash and Burn.
With 4000 as the rule of thumb, you have a lot more options picking a
landing ahead of you than going back. You also already know what's
there (you've been looking at in for the last couple of minutes), so you
don't have to wonder what the options are.
At or above 4000AGL, you have time to switch your mind out of "Takeoff"
and into "Emergency Landing" mode and evaluate options. You can get the
nose down, evaluate conditions and make your decisions. At a lower
altitude, you're still somewhere between "What the Heck?" and "Change
the Channel, Quick!" in the checklist when you run out of options.
We all have this mental image of what an engine-out is like. We got it
when our instructors pulled the throttle as a drill. "Now, look for
where you will land," we were told, as we glided along.
I can tell you from experience that IT'S NOT LIKE THAT when it happens
and you're the one in the hot seat.
Hunt around online and you'll find the video of an ultralight crash,
caught on a camera mounted to the right wing. Watch it, and marvel at
how little time elapses between the onset of SASS (Sudden Airborne
Silence Syndrome) and the destruction of the camera as he attempted to
turn from crosswind to downwind.
Marvel also at the one most egregious error that the pilot made, that of
showing off for the camera. Specifically, he didn't get enough altitude
before turning away from the runway to fly over the treetops. If his
engine had failed even three seconds earlier, he could have made a safe
landing on a road. THREE SECONDS. That was the difference between
embarrassment and disaster . . .and he lost the gamble. This video is
well worth the effort to find and watch.
Try this sometime: go out to some little airport with lots of empty
space around. Fuel up to max takeoff fuel, take off, and climb straight
to 6000AGL, staying inline with your runway and noting carefully your
exact position when you cross through 3000AGL (punch the GPS button if
you have it). This is the end of your phantom target runway. Instead
of levelling off, when you reach 6000 cut your power and try to get back
in line with the runway, through the Before Landing checklist and begin
your flare before you cross through 3000AGL. I'll bet you haven't
reached your phantom runway, lined up, when you pass through 3000AGL,
unless you're flying solo in a 4-seater. After a few attempts at this,
you can do it (remember to refuel each time, it's cheating to lighten
ship), but it takes trial-and-error.
I was taught that "minimum safe" is "minimum proven plus 30%." That's
3000AGL plus 1000AGL . . .4000AGL.
BTW, you do know the definition of "fuel emergency"? It's a Phantom
with the gear up.
Thanks for the comments,
Keith
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