I am not quite sure why the concept of hooking on only when you are ready
to launch constitutes 'negative consent'? If you subsequently see a
problem developing ahead, feel the need to fiddle with bit of kit, scratch
your crotch, or start to feel unwell, then pull off and call stop. I did
exactly that last weekend, when I noticed a motor glider starting its take
off run at the same time as as the Launch Point Controller (Marshal) was
signalling up slack for my winch launch. (To be fair to him, the pilot of
the motorglider had called some time before that he 'ready to depart',
but had delayed his actual departure for some reason. The LPC thought it
had already gone, and it was also taking off from a grass area that was
behind his back.) It doesn't remove all responsibility from the pilot.

You equally well argue that under Don's preferred system, you could be
accidentally launched if you raise one finger to pick your nose, and then
two fingers to tell the launch marshal what you think of him!

We have been teaching the BGA preferred system for quite a few years now.
That is, by accepting the cable to be hooked on you are ready to launch,
and that you will have your left hand on the release knob. If you have a
flapped glider, just set zero (or plus 1) flap for the take off run and
then reset them if necessary, once you are safely in the air. The rapid
acceleration on a winch launch should give you almost instant aileron
control, so a flapped glider in neutral flap should be no worse off than a
normal unflapped glider.

Under the old 'two finger' launching system, I often used to find that
student pilots went on signalling all the way up the launch, even though
there was nobody out there to see it at 1000ft (!), and then make a grab
for the canopy release knob, the airbrake lever, the flap lever or the
undercarriage lever when it was time to release. Obviously this would be
even more worrying if they had to pull off because a problem developed
during the ground run! I can't remember this happening since the
change.

Derek Copeland


At 01:15 19 April 2009, Don Johnstone wrote:
TIBBIN - Thumb in bum, brain in neutral.

I have always been very unhappy with the concept of negative consent,
the
requirement that a pilot has to take action to stop the launch
proceeding
rather than giving the positive "take up slack" and "all out"
signals
himself.
The current procedure, (launch marshal) was introduced to replace the
necessity for the pilot to raise the one finger for take up slack or two
for all out. This rather negates the idea that the hand could be
fiddling
with anything I would have thought. In fact the current procedure lends
itself more to misuse as neither of the pilots hands can be seen under
the
current procedure.
The problem, I would suggest, was one of pilots not being prepared
rather
than their hands being in the "wrong" place. All the current procedure
does, with it's insistance on the hand being on the release, is to give
an assurance of safety by the action rather than the underlying decision
process that needs to take place. Addressing the process and reinforcing
pilot thinking was generally ignored in favour of a requirement for hand
placement.
Whatever the reasoning the statistics show that the incidents continue
at
roughly the same rate and there is no disparity in rates between the
organisations using the original procedure and the launch marshall
system.
Simply put the incident rates do not appear to have reduced in the BGA
compared with the Air Cadets, in fact I believe the contrary may be
true.
We have in place a system which carries a risk, however small, of
launching an incapacitated pilot, and which has shown no benefit in
solving the perceived problem.
On a final note, pilots do not pull off in their gliders one hopes. They
operate the release or pull the release. I know the hand that is not
holding the control column is no longer visible, and I do not know
Lasham
that well, but I find Dels description hard to give credence to.