[ls8pilot]

So how does it do that? What do you mean by total energy? And why don't powered aircraft have them?

As @Flyin'Dutch' says they would not be helpfull to a powered aircraft - if you inadvertently slow up, and therefore climb at 200fpm you want to know about it. Also my guess is they would'nt work very well anyway - the maths (AFAIK) depend on the ability of a glider to trade height and speed very efficiently - it's quite easy to do a low level pass at 100kt plus, pull up and then complete a circuit

A PA28 or C150 etc is not as efficient as this engine-off!

PS The vapour trails are water ballast being dumped.

[terryws]

A modern high performance sailplane (such as the LS8) is so efficient it will give three successive low passes and a circuit from the limiting speed (151 kts).

Terry

[jrp]

Thanks to all who took the time to explain the intricacies of glider variometry and why we no longer rely just on the red and green pips of the Cosim vario.

[Lefty]

Boy things have got a whole lot more complicated since my gliding days (1960’s & 70’s).