Don Johnstone wrote:

I am not against a technology solution per se. What
I am against is looking for a solution which could
take years to implement when a solution is needed tomorrow.

I'm listening for that solution, but so far all I hear is more of what
we are already doing: better training and pilots that don't make
mistakes. Propose something (I don't have any good ideas).


It seems to me that several people think that the introduction
of technology will be simple, it won't. The problem
is extremely complex.

Ony if you think the problem is 40 gliders instead of 3 or 4, which is
all that was involved in the recent collisions.

Assuming that GPS is accurate
enough, it isn't (especially in vertical positioning),

When I overlay the GPS altitude traces from the last flight with my two
GPS recorders, I see the greatest deviations (one trace compared to the
other) are less than +/- 50 feet. This is less than the wingspan of my
glider! Most of the time it is less than +/- 15 feet. I think this is
good enough for gliders.

and that it updates qickly enough, it doesn't, at least
the ones we use at the moment don't,

How much more often than once a second is required? That is 25 points
per circle, which seems like plenty to me. Our speeds and accelerations
are low, so I think an even slower rate would be adequate for
thermalling and beating back and forth on a ridge.

that still leaves
the problem of keeping track of 40 gliders constantly
changing direction realtime, can AWACS do that?

Have you ever flown in a thermal with even 10 gliders? I have many
times. I can not keep track of even 10 gliders, but I can still thermal
safely when there are that many and more. We are not flying around at
random, but circling in an orderly fashion. Only the nearby gliders are
a threat that must be monitored. In any case, a system that deals with
only a few gliders will cover most of the situations.

Still
leaves the problem of how you keep the pilot informed,
display in the cockpit? I don't think so. Having sorted
out all that, what does a pilot do in response to an
urgent warning of collision, turn into another glider
which was not logged as a threat until the sudden evasive
turn was made. Technology might give the warning but
it is the human that has to react.

These are not new questions, so you can be assured that people
contemplating these systems are considering them. Systems do not spring
fully featured and perfect from the mind of an engineer, but proceed
through stages of development and testing. Exactly what problems and
benefits will appear during this process can't be predicted very well.


I personally don't think we have the technology or
expertise to design such a system or indeed the expertise
to put it in a small enough space to fit in a glider
right now, and the cost could be more than the average
glider is worth. I am not saying do nothing, what I
am saying is do something realistic and achievable
now. I have little doubt that what has been proposed
will be with us in 10 years time but it is now that
we have a problem.

I stand by what I originally wrote, humans are the
cause of accidents, humans can prevent accidents. Whether
we have the will to do it is another matter entirely.

What must we do? Propose something - we're listening.


If GPS was that accurate radar whould be obsolete

GPS _IS_ far more accurate than radar! But the system that uses it is
being deployed very slowly.

and
transponders museum items.

Some of us already believe that! But I still installed one, because that
is the current system best suited to keep me and airliners separated (it
can also help keep smaller airplanes and even skydivers away from me).

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA