(Peter Ashwood-Smith C-GZRO) wrote:

minimum radius pull is at a bit above the stall speed
so if you pull to just before the buffet you are pretty close
regardless of airspeed.

I think everyone agrees that you want to generate max lift
for minimum radius pullout, which by defintion implies Clmax
aka stalling AOA.

On the subject of airspeed, yes theoretically the minimum
radius will be achieved at the max G at which stalling AOA
may be maintained because the maneuver is completed in less
time, and thus there is less time for earth's gravity to pull
the aircraft down, ergo less altitude loss.

However this is potentially a very dangerous procedure if
not performed perfectly.

Many people like to wax eloquently upon what they would do
in various emergencies. They say that they would stop the
prop after an engine failure to extend their glide, or that
they would turn back after takeoff if they experienced an
engine failure.

Theoretically speaking, they would be correct. However if
they tried that fancy stuff in real life without considerable
practice they would quite likely kill themselves.

The critical, over-riding factor in a pullout is to get to
the stalling AOA. Yes, adding power can theoretically
somewhat improve things, but it will also kill you if you
aren't already at (and maintain) the stalling AOA - remember
radius is a function of velocity SQUARED - and you might over-G
and break the aircraft, or black out.

Increasing the G in a vertical pullout is a very dangerous
trick, especially in an ad-hoc, unpracticed scenario. Are the
benefits worth the potential cost?

Choose a gate altitude for your radius, with margin for error.
Choose a gate airspeed to keep your G within limits.

--
aboyd