At 10:24 12 July 2005, wrote:
I always understood that wind shear was 'worse' nearer
the ground. The
idea of deliberately doing turns this low with one
wing very likely to
be in a different windspeed than the other, doesn't
seem entirely
sensible to me. This experienced fellow may well handle
the situation,
but I suggest it sets a poor example to any watching
novice who may not
have the abilities to deal with whatever happens next.

Martin, UK.


I suspect the pattern speed goes up faster than the
wind shear does as you trade altitude for airspeed
so the stall margin would actually go up. Not sure
that wind shear is the main reason CH (or anyone else)
does this. I'd ask him.

I tend to carry a little extra airspeed until I'm set
up on short final. It's harder to stall/spin on the
turn to final with a little extra airspeed margin (you
never know what distraction will pop up when you are
the most busy in the pattern). I also find you get
a slightly lower angle view of the approach end of
the field sooner so in outlanding situations it can
expose hidden wires while you still have the energy
to get over them. Having talked to pilots who have
hit wires on approach, they report that the first time
they saw the wires was when the glider got low enough
that the wires came up out of the ground clutter -
by then they were too close to react and too slow to
do anything but fly into the wires.

It's important to understand how much time you need
(using landing flaps/airbrakes) to bleed off the airspeed
or you will have problems at short fields.

9B