On Wednesday 15 Jul 2009, Curtis Olson wrote: > Hi Emmanuel, > > I have done some work with 7-8' wing span RC flying wings, so > this Horton model is very interesting to me! Thanks for making > it and adding it to CVS, it looks very nice! > > I don't know how the full scale aircraft flies, but if it flies > anything like my RC wings, it will be very sensitive in pitch > (maybe more than it is now, but that also would depend a bit on > control rigging), roll will be slow, and it should glide forever > power off ... like a slope soarer. The real thing might have > more drag than mine, especially with the gear down, but I would > expect a very long shallow glide slope with this. > > Also I would expect a lot of adverse yaw and basic lack of yaw > stability ... it will eventually stabilize out in heading, but it > would probably wander around a bit in yaw and small roll changes > would probably induce some yaw changes that take a while to > settle out. But that's based on my smaller models ... there may > be things they did with the control rigging to minimize these > tendencies. > > With my models we don't have separate elevator and ailerons ... > so you can't do offset aileron throws to compensate for adverse > yaw ... because any unequal throw in the ailerons translates to a > pitch change ... basically the elevator position is the average > of the two surfaces and aileron position is the difference > between the two surface positions. > > Anyway, very neat stuff, I really love how you and others take so > much time to accurately model all these wonderful historical > aircraft! > > Another interesting thing I'd love to see modeled is the Arup > flying wing. Just a couple weeks ago I got a chance to speak to > one of the test pilots (now in his 70's) and he was telling us > stories about how well it flew and how nice and forgiving it was. > He did a drag race with the Arup (46hp motor) against a new > corvette with a couple hundred horse power once down the length > of the runway. He fired up the engine and was quickly airborne > and flew the length of the runway in ground effect. When he > crossed over the end, he looked back to see where the big > powerful corvette was and it was only about 1/3 of the way down > the (grass) runway fish tailing all over the place. He won an > easy $5 that day. I also have access to a bunch of video of test > flights of the Arup ... I'm hoping to be able to get a copy in a > couple weeks. > > Best regards, > > Curt.
The X/YB-35/49s certainly suffered from yaw instability problems; in one YB-49 bomb run test it took the pilot four minutes to stabilise the aircraft, during which time the bombardier became airsick. This compares pretty badly with the B-29, which only took a max of 45 seconds to stabilise. The YB-49s weren't fitted with autopilots though, which would have helped. The B-2, of course, is fitted with a modern FBW FCS, which controls the split aileron airbrakes to keep the yaw under control. Incidentally, Edwards AFB is named after one of the YB-49 test pilots who died in a YB-49 crash. The Arup design was resurrected in the Vought V-173 'Flying Pancake' Sadly, I couldn't find any real Horten Ho IX footage on youtube but there's a clip of the Ho 2 glider at: http://www.youtube.com/watch?v=GjXr5w3M4mc There's some footage too, of the Arup at: http://www.youtube.com/watch?v=Nxz1UF67EQI You can see the V-173 at: http://www.youtube.com/watch?v=LfpTDOAfj7Y and also worth looking at, in the context of the Horten and other flying wings, is the Armstrong Whitworth AW-52: http://www.youtube.com/watch?v=7H1tyMRtcho LeeE ------------------------------------------------------------------------------ Enter the BlackBerry Developer Challenge This is your chance to win up to $100,000 in prizes! For a limited time, vendors submitting new applications to BlackBerry App World(TM) will have the opportunity to enter the BlackBerry Developer Challenge. See full prize details at: http://p.sf.net/sfu/Challenge _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
