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I would have thought it'd be the leading edge, but the idea was if I could determine the span, and the chord, and I sweep the wing, I was curious if I could compute the new span with that data. That's probably why I figured trig would be necessary,Well, it would require knowing the sweep of the trailing edge and the span somewhere.
I think you have to consider a lot of things like the centre of lift to avoid producing a lawn dart.I would have thought it'd be the leading edge, but the idea was if I could determine the span, and the chord, and I sweep the wing, I was curious if I could compute the new span with that data. That's probably why I figured trig would be necessary,
Yes, but it was done successfully with several early jets. F9F Panther into the Cougar, for example.I think you have to consider a lot of things like the centre of lift to avoid producing a lawn dart.
It was done with the 262 to adjust CoG.Yes, but it was done successfully with several early jets. F9F Panther into the Cougar, for example.
Not to move it, but to maintain it with heavier engines. From wiki "The Me 262 is often referred to as a "swept wing" design as the production aircraft had a small, but significant leading edge sweep of 18.5° which likely provided an advantage by increasing the critical Mach number.[22] Sweep, uncommon at the time, was added after the initial design of the aircraft. The engines proved heavier than originally expected, and the sweep was added primarily to position the center of lift properly relative to the center of mass. (The original 35° sweep, proposed by Adolf Busemann, was not adopted.)[23] On 1 March 1940, instead of moving the wing backward on its mount, the outer wing was re-positioned slightly aft; the trailing edge of the midsection of the wing remained unswept.[24] Based on data from the AVA Göttingen and wind tunnel results, the inboard section's leading edge (between the nacelle and wing root) was later swept to the same angle as the outer panels, from the "V6" sixth prototype onward throughout volume production. "CoL or CoP? Did they really sweep the wings to move the center of gravity?
Eh? In the link it says "position the center of lift properly relative to the center of mass. " The adjustments were to get the centre of mass and the centre of lift in the same place.OK, so it wasn't swept to move CoG, but to move CoL.
You can move CoG and CoL independently along the length of the aircraft. They weren't trying to shift the COG along the length of the aircraft to get the CoG and CoL positioned correctly relative to each other, they were trying to change the lift distribution to move the CoL. Sweeping the wings actually moves the CoG in the wrong direction.Eh? In the link it says "position the center of lift properly relative to the center of mass. " The adjustments were to get the centre of mass and the centre of lift in the same place.
Yes of course, and also by changing the engines construction and materials you can change its centre of mass. Now do you start changing all you worked out about the engine and its aerodynamics or keep the same mounting and jiggle with how it sits in the airframe, which could mean sweeping the wings back a little, but no more than something like a DC-3. I presume what GregP pointed out was a relationship that was true for the original design and for the revision, the position of CoL and CoG would be relatively the same.You can move CoG and CoL independently along the length of the aircraft. They weren't trying to shift the COG along the length of the aircraft to get the CoG and CoL positioned correctly relative to each other, they were trying to change the lift distribution to move the CoL. Sweeping the wings actually moves the CoG in the wrong direction.
Sweeping the leading edge more than the trailing edge actually moves the CoG backwards a little, assuming that you're not also moving the wing forward, etc., etc., etc.
As GregP astutely points out, Messerschmidt specifically did not want the CoG and CoL in the same place. "Same place" and "position[ed] ... properly" are not the exact same thing. You'll notice that that text you quoted states: "On 1 March 1940, instead of moving the wing backward on its mount, the outer wing was re-positioned slightly aft ..." If they were trying to move the CoG aft, this would have been a far better solution.