Bill Daniels wrote:
"BB" wrote in message
...
I mean, when I think about it, I come to the conclusion that you
always have to (and can only) optimise your speed through the airmass
by flying MC (putting aside what that actually means in reality). If
the resultant XC speed given by MC theory is less than the windspeed,
well, you're stuffed.

Dan
That's correct. The assumption is that you're flying in thermals, and
thermals drift with the airmass. Actually thermals usually drift a bit
less than airmass, and if you've got ridge or wave, those are
stationary with respect to the ground. But otherwise, by definition
there is no way to fly faster than the optimum speed through the
airmasss -- the fact that the ground is moving around below you is
irrelevant.

John Cochrane

For the ultimate competitor, going fast is their reason for being so the
MacCready formula is very important for them.

My experience with talking to "ultimate competitors" is that the
MacCready formula isn't even on their radar. It's mainly a topic the
rest of us obsess over, because we think it we just understood it well
enough, we'd go as fast as those other guys. The "ultimate" pilots know
the MC speed isn't important because we rarely fly in pure MC condtions,
and in any case, "risk management" means flying slower to optimize the
chances of finishing the task. John Cochrane's article is a wonderful
exposition of this.

--
Eric Greenwell - Washington State, USA
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