New winch height record

John,

With the Tost winches we use at Lasham, the pilot has
no control over the speed, unlike the torque or tension
controlled Supacat or MEL winches. Nethertheless he
is still expected to monitor the airspeed, especially
during the safety climb, and not to initiate the rotation
until it is adequate. After that we expect him to hold
a steady attitude and allow the winch driver to control
the speed and power. If the airspeed gets too high
the pilot signals to the winch driver by waggling the
tail with the rudder. If it gets too slow, he lowers
the nose slightly to reduce the risk of stalling and
also to signal to the driver that more power is required.
The pilot could also of course be a she.

The original question from Dan G was what do we teach
at Lasham, where we have very powerful winches (as
does his own club). You may have to climb more gently
with less powerful winches. The point you make is a
good one.

Del Copeland

At 10:54 01 December 2007, John Smith wrote:
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.

Del C wrote:
John,

With the Tost winches we use at Lasham, the pilot has
no control over the speed, unlike the torque or tension
controlled Supacat or MEL winches.

Exactly the same applies to a V-8 diesel Supacat with its high torque
output - an Ash-25 might control the winch speed but a K-21 has no chance.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

Del C wrote:

With the Tost winches we use at Lasham, the pilot has
no control over the speed,

We have a Tost winch, too, and the pilot has definitely some degree of
control over the speed. The winch driver gives the tension depending on
how much the pilots pulls. But then the winch driver holds that tension
and the pilot makes the fine adjustments. No way a winch driver could
adjust precisely and quickly enough.

It's like a dialogue between the winch driver and the pilot. It requires
a certain experience and feeling from both to yield good results.

But having winched at many sites, I know that there are huge differences
among the "winch cultures". A pilot must be able to immediately feel how
he is winched and to adopt accordingly.

"John Smith" wrote in message
...
Del C wrote:

With the Tost winches we use at Lasham, the pilot has
no control over the speed,

We have a Tost winch, too, and the pilot has definitely some degree of
control over the speed. The winch driver gives the tension depending on
how much the pilots pulls. But then the winch driver holds that tension
and the pilot makes the fine adjustments. No way a winch driver could
adjust precisely and quickly enough.

It's like a dialogue between the winch driver and the pilot. It requires a
certain experience and feeling from both to yield good results.

But having winched at many sites, I know that there are huge differences
among the "winch cultures". A pilot must be able to immediately feel how
he is winched and to adopt accordingly.

Winch culltures and varying winch driver techniques is one reason computer
controlled cable tension is such a good idea. It puts the airspeed control
firmly in the hands of the pilot. You get a near perfect launch every time
in every glider pretty much regardless of conditions.

Bill Daniels