<snip>

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
<snip>

Yikes Keith!
You might want to independently verify that bit of info.  It may save
your plane and your life.
I have to reeeally disagree with the "blanket" straight ahead from
4000'AGL.  There is time to look out the side window.

What kind of aircraft were you flying?

Like everything else, the correct answer is - it depends.
-> On aircraft, HP, glide ratio, weight, headwinds, density
altitude(more for climbout angle), departure type...
Many (dirtier/underpowered) aircraft will NOT make it back to the
airport under most circumstances.
Twins get a better selection of crash site :)

Before you go flying next, calculate a rough climbout (climb angle) and
your glide distance (glide angle) minus a point for dings and dirt.
If the prop is windmilling, the descent will be steeper.  Reduction
drive conversions probably more so.

You should have a good idea how much altitude you will lose doing a 180
near best glide.
The next time out flying, try a few cordinated steep/minimum radius
turns power off at different angles say 30, 45, 60* degrees angle of bank
to see your height loss/turn radius at ALTITUDE.  This may give you
another option.
Later, if the circuit is quiet, do a few simulated failures.

Know your aircraft...
Cary

Notice all the cr-- er, all the STUFF you have to consider?  When things
get suddenly quiet is one heck of a time to start doing your math homework!

The correct answer is to know ahead of time what the answer is.  If you
aren't absolutely sure, then you follow the rule of thumb.  Far better
to have to explain to the NTSB why you landed in a schoolyard than to
have the NTSB explain to your family why you died.

BTW, I've done hundreds of simulated failures over the years.  They bear
the same relationship to the real thing that you get when simulating
cattle roping by lassoing a sawhorse.

Keith

Hi Keith;
Agreed, as implied, the point is KNOW BEFORE, so you have the knowledge
to make an informed decision.
By all means, run a few what-if calculations.  How about with a 10/20/30
knot headwind?  Test them.  There are glide calculators...
Give yourself a go/no go height.  Discuss them with your buddies.  Run a
spot landing contest...

e.g. rough calculations for a C150 - standard day, sea level, zero wind.
670fpm@68KIAS climb, 750fpm sink rate@60KIAS glide ratio ~8(when new),
say 200' height loss doing 180turn.  Say 2000' climb from a short strip.
Notice you are already in the hole as the maximum climb rate is lower
than the sink rate and at a higher airspeed.

1.  2000'/670' = 3 minutes climb. distance travelled = 68k*3min/60 =

3.4NM*6076' = 20658'.
   Glide distance = 2000'-200' for turn = 1800' * 8 = 14400' -> Doesn't
look good?

2.  With a 10 knot headwind, you will travel less distance for the same
climb (10k*3min/60 = 0.5NM) and have a tailwind on the glide back
   (1800'/750fpm sink=2.4min glide * 10NM/60min = .4NM).  So,
0.5NM+0.4NM=0.9NM * 6076' =5468' + 14400' base glide = 19544'

   -> Getting closer...a stronger wind, better climb, longer runway
might make the difference.
   Add 20% to glide for Wittman types who stop the prop.

Again, it all depends.  Unfortunately, as you allude, too many of these
end in a stall spin fatal - that is another training issue.
Don't doddle in the cockpit, make the turn immediately to the closest
runway (or field) as you trim the glide,  re-evaluate.
You know your altitude and you have been watching all those rocks,
trees, water, buildings and fields on the climbout, haven't you?
Your instructor stating the blanket 4000' straight ahead would fail his
private forced approach from any flight test I have heard of.
And, Yes, there is a pucker factor - practice is the key.
Also nothing like your first "dark" night landing, 200' rope break,
won't have the opportunity to do a night carrier...
Cheers
Cary

FWIW - the climb rate and first calculation are an optimistic
assumption.  I was waiting for someone to correct it :(
IIRC, the by the book POH climb out rate/distance is worse and the
numbers work out to something like an 18K headwind...

Cheers
Cary



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