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**Bertie the Bunyip[_25_]** · April 25th 08, 12:06 PM posted to rec.aviation.piloting,rec.aviation.student

WingFlaps wrote in news:ac05ca83-bbc8-4c3b-9469-
:

On Apr 25, 8:31*pm, Stefan wrote:
WingFlaps schrieb:

Try reading the statement again, here it is:
"Now we add in the energy losses from having to accelerate with
the
wind and to glide speed."
To summarise your missed point, the pilot control inputs cost
energy
that is not factored into simple glide/time analysis.

This is absolutely correct. But then, I dont understand the
connection
to your first statement regarding the wind. Additioinal drag by
control
input is completely unrelated to the presence or non-presence of
wind.

Itls a turn upwind to downwind. That involves 2 direction changes, one
to reverse course and the the other to line up the runway. If there's
wind there will be an effect on line up. Try thinking about more
factors that cost altitude OK?

It's not so much the loss of altitude that will get you in this
manuever. it's the probable loss of control trying to manuever around
back towards the field.
Firstly, in any emergency that hasnt been drilled, you will have a
moment where you will be sitting there with your mouth open in utter
disbelief of what has just happened. in fact, even if you have drilled
for it you will still have this moment, but if it's been practiced the
moment you begine to do something about it will be sooner coming.
While you're sitting there wondering what's going on, the speed will be
bleeding off. Not good. Then, you will have to manuever the airplane
around using rapid manuevering at a relatively high bank angle if you're
going to make it (I'm assuiming you're still pretty low) and if you
aren't 100% au fait with this sort of flying you're going to be very
lucky to be able to maintain control of the airplane before the ground
reaches up and smites you. This is less about the maths than the
pilot;'s proficiency. The pilot who is proficient enough to do this will
have determined an altitude above which he knows it is possible to do it
and so the question will not be one of whether it's within the
performance capabilities of the airplane, but one of whether the pilot
can accurately control the airplane through the required manuever.
Here is what you'll have to do the instant the engine gives up:
Smooothly lower the nose as you roll just as smoothly, but as quickly as
possible, towards the crosswind, if any. You will have to continue to
lower the nose as the turn, which should ideally have at least 60 deg of
bank, is completed. you should be just nibbling the stall during this,
and , needless to say, perfectly co-ordinated. Pitch control is now
critical as what you're trying to do is cheat physics by offloading the
wing as you turn. a 60 degree bank in level flight will give you a stall
speed of 1.4 VSO and you should be below that so you're right on the
edge. This is all about having very good seat of the pants capability
based on experience. As you approach the desired heading to your landing
spot, you have to smoothly roll out and get the nose up and back to a
good glide attitude. You'll have sacrificed some altitude doing the
sharp turn, but far less than you would have making a wider turn with a
gentle bank. As you level the wings, you should be on, or close to, your
desired glide speed. This is a difficult manuever to pull off. Even
practicing at a bit of altitude has some risks. you're going to pull a
bit of G and it's easy to lose the plot and either spin out of it or
overstress the airframe praciticing it unless you know what you're
doing. It's not really something that most pilots should even consider.
Someone flying 25 hours a year s unlikely ever to become sharp enough to
do this reliably. I certainly wouldn't try it now unless there was no
choice.
There's a lot of crap talked about turning back and most of the
accidents occuring as a result of this are because the pilot has heard
it's possible and decides to learn how to do it when it actually
happens. Most modern flight manuals tell you it isn't possible but this
advice is ignored by guys who reckon they're a cut above because they
did the math or tried it once or twice at altitude or because they read
about it here.

Bertie