STF question

Ramy wrote:
On Mar 14, 6:51 pm, Gary Emerson wrote:
toad wrote:
Standard STF theory says that the head/tail wind does not matter for
cruise flight. Does wind influence best speed for final glide ?
Todd Smith
3S
It's two separate issues. Speed to fly AND altitude required. Speed to
fly is NOT dependent on HW/TW. HW/TW will affect Altitude required.

HW/TW also effect speed to fly to achive best glide over the ground.
The rule of thumb is to add half the wind speed to the best glide
speed. I am also not sure it doesn't matter for cruise flight. If you
have a 50 knots head wind you will not make any progress unless you
fly very fast. From what I understand from cambridge manuals they do
not take the wind into account for speed to fly.

I have a 302, and I'm sure you are right, because "speed to fly" does
not depend on the wind. If you want to know the "speed to fly to achieve
the greatest distance over the ground into a wind", then you can (1) use
your rule of thumb, (2) use the MC setting that gives a theoretical
cross-country speed equal to the wind (another rule of thumb), (3) let
Winpilot (or perhaps one of the others) figure it out for you.

If you have a flight computer, you might be able to find the best
speed/MC setting by watching the arrival height for a point in front of
you while you adjust the MC from 0 upwards. I haven't tried that, but it
sounds good.

--
Eric Greenwell - Washington State, USA
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