High Speed Passes & the FAA

At 19:06 05 October 2003, Marc Ramsey wrote:
I'm not a mathematician, but I think you'll find that
the point you should be aiming for on the cylinder

is on the line from your current position to the
center of the cylinder. Since, as far as I know,
your computer is guiding you towards the center
of the cylinder from your current position,
then you will cross that optimal point.

This is correct - the shortest distance to the cylinder
is on a radial from the center.

Frankly, if your computer can't help you navigate to
the desired height at the edge of the cylinder, yell

at the designer, or get a new instrument or software.

This isn't rocket science.

I think the point is navigating to a point in space
requires monitoring glide angle to the 500'/1mile point.
I am aware of computers that beep when you cross the
cylinder, but not of any that tell you along the way
if you are GOING TO make it. This is what requires
the heads-down time. Or leaving a minute or so of time
on the clock for enough extra altitude to not have
to worry about it.

Also, the 'get a new computer' point contradicts the
purported logic for recent rules changes (such as 15
min) - that it excludes some pilots from competition
to require the 'latest and greatest' computer technology.
I don't buy that logic and it looks like you don't
either, but it is out there.

BTW, if you look carefully at SSA contest rules 10.9.3,
it states quite clearly that a finish is recorded when
you enter the 3 dimensional cylinder. It does not
say you have to enter at the edge, you can also enter
through the bottom. What this means is that even if
you cross the edge of the cylinder at lower than the
minimum height, as long as you can pull up and get
a single fix within the cylinder, you've got a finish.


Now, some buttheads somewhere will no doubt start
coming in below the cylinder and pulling up through

the center, figuring this will give them a speed
advantage. It won't, since while you finish time is

recorded where you enter the cylinder, your
finish distance only goes to the edge.

Actually, I think the optimal is to be close to zero
feet just before 1 mile, then do a ballistic pullup
(to roughly zero mph - depending on initial speed)
right at 500' and 1 mile (kind of like pole vaulting).
This presumes you carry extra potential energy on the
glide as a buffer. Otherwise the optimal is to fly
Mc speed corresponding to your last climb right to
the 500'/1 mi point. If you hit a little sink you could
do a mini-ballistic pullup at the edge or go hunting
for lift (at 500'). This potential practice is the
logic behind John Cochrane's finish donut suggestion
- the cost of which is even more pressure on heads
down computer time to clear the 1-mile deep donut and/or
trying to find lift to reach the bottom of the cylinder.

I am not recommending any of these techniques - it's
just what the rules encourage the foolhardy (or desparate)
to try.

At least with the finish at ground level at the airport
you have a continuous visual reference as to whether
you are gaining or losing on the glide angle, keeping
the pilot's head out of the cockpit - that's the main
point.

9B