Two proposals to explore Dynamic Soaring

Actually, the desired instrument is the "MEMS Inertial Variometer" currently
under development by al least one European group. Total energy variometry
in the inertial domain needs no air data and so displays the rate of energy
gain or loss without gust sensitivity. It might be interesting or even
useful to display the difference between this and an air data based TE vario
but the inertial TE vario would give the needed data.

Bill Daniels


"Eric Greenwell" wrote in message
news:uDcsh.693$Kf.554@trndny07...
Matt Herron Jr. wrote:

Of course we could locate convergence lines with this instrument as
well. Who knows, we might even get thermal information from the
ability to detect horizontal gusts.

You might already have the instrument you desire. Our total-energy
compensated varios already detect horizontal gusts. In thermal flying, the
trick is to determine the difference between those and air going
vertically. So, I think you ought to proceed immediately to proposal #2.
Perhaps there are simulators with good modeling of a glider's dynamic
flight and allow airflows to be simulated. I suspect you are right, that
it will be much easier to learn on a simulator than in actual flight!
Later, perhaps the instrument characteristics needed will be more evident,
and one could be built.


Proposal #2
While it is possible to design and build this new instrument, and just
how to do it will make an interesting discussion in itself, it will
take some time to perfect it and get it into production. In the mean
time, we want to learn how to use it before we have it. Just like the
albatross has several different techniques for taking advantage of the
same surface shear conditions, there are probably many new ways that
have not been discovered at "full" scale to soar dynamically. What
is the best way to fly in wind gradients that run side to side, rather
than top to bottom? What is the best way to dynamically soar
orthogonal to the wind direction?

While our instrument is difficult to build in the real world, it's a
snap to create in a flight simulator where the glider is already fully
modeled. Lets build a virtual instrument and experiment by flying in
virtual shear using one of the excellent glider flight simulators on
the market. Anyone have an in with the programmers?

I suspect a practical problem will be finding shear large enough for the
typical glider. Birds do it, model airplanes do it, maybe a microlight
glider can do it, but these all turn quite sharply compared to our 15 m
and up gliders.

--
Eric Greenwell - Washington State, USA
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