New winch height record

At Lasham for the K21 we teach holding the stick about
two-thirds of the way forward for the ground run and
safety climb and then easing back to give the correct
climb angle with the wingtips about 45 degrees to the
horizon. You don't have to pull back quite so hard
to achieve this as you do in our K13 basic trainers,
and you shouldn't be right on the back stop.

Incidentally the K21 will do a perfectly acceptable
(although not optimal) winch launch if you just hold
the stick in the centre of the elevator range and leave
it there throughout the launch. It is probably the
easiest and safest glider to winch launch there is,
with a very wide speed range (anywhere between 50 and
81 knots will do), and very benign stalling characteristics.


Del Copeland

At 00:24 30 November 2007, Dan G wrote:
On Nov 29, 11:34 pm, Del C
wrote:
The K21 seems to climb as well as anything on a winch
launch, despite being a bit big and heavy. Probably
only a K8 will beat it.

I agree although last weekend it was so windy the K8
was just getting
blown about all over the place and in the hands of
several pilots,
including our DCFI, was only getting 1,500', compared
to 1,900-2,000'
for the K21 (assuming the weak link didn't break on
the way up). In
calmer conditions the 8 usually has the edge.

What does Lasham teach on stick position for the 21
during launch?

We have a couple of DG1000s and they don't climb quite
as well. If you pull the stick well back, a sort of
pitching motion seems to set in as though the elevator
is stalling.

I had that in a K13 once - it's definitely the tailplane
stalling.
Quite an interesting experience.


Dan

Del C wrote:

At Lasham for the K21 we teach holding the stick about
two-thirds of the way forward for the ground run and
safety climb and then easing back to give the correct
climb angle with the wingtips about 45 degrees to the
....

I consider this mechanical approach completely wrong.

On the ground run, use the stick as needed to keep the glider on the
ground. (This may or may not be 2/3 forward.) (Personally, I start with
the stick fully forward and then ease it slowly back until the glider
begins to fly. I have no idea at which stick position this happens.)

On initial climb, use the stick as needed to do a smooth transition, and
watch your speed.

On climb, use the stick as needed to keep your target speed. (If this
means neutral or at the back stop, so be it.)

Your target speed dictates the climb angle, and this may or may not be
45 dgrees, depending on the winch and the glider and probably a lot of
other things.

If you teach a mechanical apporach, then you are going to be in big
trouble if sometimes you happen to fly at a different location.