Geriaviator and Stanwell,
8-16:1 seems on the low side for any glider. I've read somewhere that the old "rule of three" still applies, even with modern wide-bodied jets (three air miles run per 1,000 ft lost at flight idle). Even with statute miles that's almost 16:1, with nautical 18:1.
May well be that I don't know what I'm talking about - someone will put me right !
Pom Pax,
Thanks, but I don't think I'll bother !
Danny.