rmiller@i88.isc.com (Richard J. Miller) (08/28/90)
From: rmiller@i88.isc.com (Richard J. Miller) <From: Will Martin <wmartin@STL-06SIMA.ARMY.MIL> ... <What is the effect on the towplane's internal load capacity when it tows a <glider on takeoff? <..., but then one realizes that the gliders <provide their own lift, and support their own weight. So the towplane just <has to provide forward momentum. < <But then one thinks about takeoff -- pulling the loaded glider from a dead <start would have to take the towplane's entire capacity, so it couldn't <also be carrying its usual load. So then this one, at least, gets <confused. Do glider-towing bombers or cargo planes fly empty, carry a <reduced load of ordnance or cargo, or can they carry their full usual <load in addition to towing the glider? (If the latter, it certainly adds <to the arguments in favor of gliders! But it sure sounds like a free <lunch... :-) < <Regards, Will it takes (possibly MUCH) more runway, but there still is no significant capacity problem with towing. the primary problem was starting the takeoff roll (as in getting the glider out of the rut it was sitting in) and then getting up to flying speed (the glider should usually be able to lift off first, which helps). even the old, flimsy, ugly ones probably added only a couple hundred pounds of drag (note drag, NOT weight) to the towplane, which is not real significant considering what they could carry themselves. this is, in fact, the exact reason why the US was looking at gliders at the beginning of WWII, there were simply not enough cargo aircraft available and gliders provided a easy and cheap way to get more cargo capability. that problem slowly became less important by the last year of the war and the disadvantages of gliders such as maneuverability were being felt more in the missions that were needed. since then the cargo lifters have gotten faster to the point of making it very unpleasant to pull something with them! Rich Miller Interactive Systems Corporation rmiller@i88.isc.com {sun, amdahl, att (maybe)}!laidbak!rmiller