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Flying wing as cheap and simple option for basic fun flying.

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Aesquire

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Another potential issue with powered wheels as a launch booster is popping wheelies. Short coupled aircraft like a LongEZ and presumably a plank with trike gear have the center of gravity just ahead of the main gear. Nose up rotation from the main gear motors could happen before aerodynamic control can compensate.

Mostly, though, I object to any mass that doesn't create lift, thrust or decrease drag. ( comfort and range are good too... )

How about a nice thick wing with the center section covered in modern transparent sail "cloth"? Wood or aluminum tube & gusset.
 

patrickrio

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Aug 15, 2020
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Those are launch test vehicles specifically designed for testing the electromagnetic catapult system. You can change the mass easily by loading them differently. It allows testing of the wide force variations required to launch dramatically different sizes of aircraft, from small drones to large passenger transports.
 

Aesquire

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Tossing used cars off carrier catapults is a time honored tradition. Way cheaper than an instrumented test sled. 2004 Impala weighs x, do the calculations as to how far X will go, with dialed in weight of Y, and toss. Did you make the distance? Yea!
 

Norman

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Back to tailless aircraft. The level of precision necessary is something that may be overlooked. The U-2 I helped with had several small yet significant errors. Surface finish and geometry must be controlled relatively tightly to have an efficient airplane that's also pleasant to fly. We've talked about surface geometric tolerances before. What I want to stress here is the importance of washout and how it will affect handling. 1/2 a degree of incidence variance between the wing tips isn't good for any airplane but the pilot of a conventional airplane can trim out the rolling and yawing moments because the ailerons and rudder are not coupled. In a flying wing roll and yaw are coupled to some extent and 1/2 a degree of extra twist in one wing may be more than can be trimmed out because trimming roll will cause yaw and visa versa, certainly a full degree will make your 'wing un-trimable. An airplane that can't be trimmed for straight and level flight is going to be tiring at minimum and possibly dangerous. This means that you'll need to build a jig for the wing. "No problem" I hear you say "most wings require some form of jig". That's true but often all you need to do is make sure that leading and trailing edges are straight. For planks and most swept tailless 'wings that's enough but for BSLD wings one or both edges have a shallow curve that requires a real jig. "Fine" you say "we want it simple and cheap and fancy jigs just make things un-simple so we'll build it with straight edges". You could do that but to solve the adverse yaw problem you'll still have to make the lift distribution non-elliptical and if that's not built into the wing you have to get it by reflexing the elevons which is less efficient than building it into the wing. That linear washout wing will also be more susceptible to tip stall than a BSLD wing. Lots of circular problems and the solution to most of them seems to be to take the time to build a good flat table and a jig for a BSLD wing. Nobody has done this in full scale yet so here's a video of a guy laying up the spars and ribs for a BSLD model. Oh BTW it's a plank. Yeah apparently BSLD works for tapered planks.

 
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rotax618

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Evans Head Australia
The terms “Prandtl, BSLD’ are an oxymoron when used with the premise of “FLYING WING AS A CHEAP SIMPLE OPTION” .
My understanding of “Cheap, Simple” is a plank, a constant chord swept wing, a Verhees type delta etc. As has been pointed out to get BSDL and Prandtl wing to work requires extreme accuracy in shape and surface finish, not cheap and simple.
 

cluttonfred

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That!

The terms “Prandtl, BSLD’ are an oxymoron when used with the premise of “FLYING WING AS A CHEAP SIMPLE OPTION” .
My understanding of “Cheap, Simple” is a plank, a constant chord swept wing, a Verhees type delta etc. As has been pointed out to get BSDL and Prandtl wing to work requires extreme accuracy in shape and surface finish, not cheap and simple.
 

erkki67

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I’ll give some chances to the idea of Koen’s wing as well, the windows issue is bugging me a bit.

further, how to get into the wing, looks very sporty.

lay on top, and the access issues are solved!
 

nestofdragons

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Koen, do you have the plans of the fuselage and rudder of this one?
Sadly not. It was a design by Ragwing. But it never got to production due to crash. I was told that the designer did not take wing design advise from the people who knew the general mistakes in Flying Flea design. Yes, it was a American Flying Flea project.
 

nestofdragons

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During a brainstorm about how many HP a airplane needs, my team came up with the idea that if the airplane is airborne, you need just enough to make it climb. But you need a lot power to get it rolling to take off speed. Electric energy would be lot for just the roll out. So ... i came with the idea for a fun-flying trainer to get it airborne using the very old system of bungees. Once airborne ... electric power to rise to soarheight. Soar ... land ... pull out battery, place new pilot and battery, pull the bungees and off you go again. Man ... that would be fun.
 

Riggerrob

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Tossing used cars off carrier catapults is a time honored tradition. Way cheaper than an instrumented test sled. 2004 Impala weighs x, do the calculations as to how far X will go, with dialed in weight of Y, and toss. Did you make the distance? Yea!
A few years back, some prankster posted a photo of a car catapulting from an aircraft carrier and labeled it; "USN's new catch-and-release program for Taliban."
Hah!
Hah!
 

nestofdragons

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I’ll give some chances to the idea of Koen’s wing as well, the windows issue is bugging me a bit.
Which proposal of me are you referring to? The old looking fuselage with very large wheels? If yes, when you can place pilots head about at location of trailing edge, it should not be a problem. Just cut a half circle in the trailing edge and you fit in just like in a SWIFT hangglider. Easy.
Or you are referring to the low aspect ratio which i show below. Access might be easy. Just as easy as the Verhees Delta. Just get inside it from the rear. You can use the same technique i used to get inside my enclosed recumbent bike. Just sit (facing backward) on top of vehicle just after the seat. Rotate your body till your legs are directed to the cockpit and slide in. All you need to do is make a harder area on top of rear spar in this picture, i guess.
2020-10-16 LAR2.jpg2020-10-16 LAR.jpg
 
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