Interesting discussion - >From my experience the following can make a huge impact on litres per launch figures.
The weather on the day and what kind of operations you're towing for. Good thermal day with pilots that you can aggressively thermal on tow with, the glider can be off tow at 1500ft. Someone has already mentioned good ground management can reduce ground turn-round time. Gliders not maintaining station increases drag and increases time and therefore fuel burn. Wave day launches are heavy on fuel; rotor and turbulence down low followed by high launches sometimes through areas of heavy sink to higher altitudes where combination performance is reduced. Now if your really worried about how much fuel we use for launches have you asked yourself how many litres of fuel we used to drive to the airfield, could I car pool, and do I really need big 4WD or V8? Let's just enjoy our flying what ever it costs. SDF -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Alan WIlson Sent: Monday, 19 March 2007 7:02 PM To: 'Discussion of issues relating to Soaring in Australia.' Subject: RE: [Aus-soaring] Towplanes litres per launch Lies, dam lies and statistics. But attached are some stats I took at a competition in FEB 05 For the argument, whatever it is trying to prove. Alan Wilson A tuggie, etc.. Canberra Gliding Club. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Michael Derry Sent: Monday, 19 March 2007 5:13 PM To: Discussion of issues relating to Soaring in Australia. Subject: [Aus-soaring] Towplanes litres per launch Mike If you want an accurate answer you will really have to specify how people calculate it and who gives you the info. If you ask an aerotow buff he is likely to look on the optimistic side of how much his needle moved on his gauges when a had a good run to give you his likely estimate. If you had someone like me, I would look at how many litres the club was invoiced for over say a 12 month period and divide it by the number of launches (after allowing for opening and closing stocks and onsales of fuel to other users). This will give you the average per launch and depending on the club's record keeping system it is relatively easy to calculate the average launch height. There are figures and there are figures ! Michael Derry On Mon, 19 Mar 2007 15:26:55 +1000 Mike Borgelt <[EMAIL PROTECTED]> wrote: > > Here's a new towplane: > > http://www.windcraft.fi/pik27/welcome.htm > > Might be somewhat more efficient than a Pawnee. I once calculated > that of the 235HP in the Pawnee about 25 was effectively climbing a > 500 KG glider on tow. A stunning 11% or so efficiency and that > doesn't even account for the Pawnee's descent. About half the Pawnee > installed power is lost in the prop at climb speed. These are > approximate numbers. > > So how many tows per hour and liters per hour are Pawnee towplane > operators getting? Liters per 2000 foot tow would be an interesting number. > > Mike > > > Borgelt Instruments - manufacturers of quality soaring instruments > phone Int'l + 61 746 355784 > fax Int'l + 61 746 358796 > cellphone Int'l + 61 428 355784 > Int'l + 61 429 355784 > email: [EMAIL PROTECTED] > website: www.borgeltinstruments.com > _______________________________________________ > Aus-soaring mailing list > [email protected] > To check or change subscription details, visit: > http://lists.internode.on.net/mailman/listinfo/aus-soaring A 6913 _______________________________________________ Aus-soaring mailing list [email protected] To check or change subscription details, visit: http://lists.internode.on.net/mailman/listinfo/aus-soaring No virus found in this incoming message Checked by PC Tools AntiVirus (3.1.0.10 - 9.064.003). http://www.pctools.com/anti-virus/ No virus found in this outgoing message Checked by PC Tools AntiVirus (3.1.0.10 - 9.064.003). http://www.pctools.com/anti-virus/ _______________________________________________ Aus-soaring mailing list [email protected] To check or change subscription details, visit: http://lists.internode.on.net/mailman/listinfo/aus-soaring
