An X-15 wing planform question (Monogram and MPM)

Maybe my geometry is wrong, but wouldn't adding a wedge to the angle increase it? I would think a wedge of 2 degrees should be removed, possibly from the wing root.

I think you must first determine if either the root chord or the tip chord is the correct length, then adjust the other to be the correct length which should correct the TE angle. It is possible that both chords are incorrect requiring a quadrilateral rather than a wedge for correction.

jack g

You're correct, I forgot to mention that the writer reported that the root chord was correct. Therefore the tip chord needs to be extended aft about 1.2 mm. I would like to verify his correction before I change my model, hence my question. None of my X-15 sources has the required data.

Rob

My models:

Thanks, excellent find! Assuming the information is correct, the Monogram kit agrees pretty well:

- I made a planform sketch of the model to determine the root chord at the aircraft's centerline, and came up with 63.5 mm, which translates to

- the model's tip chord is 12.9 mm average, translating to 3.05 feet

That agrees reasonably well with the quoted 14.91 ft and 2.98 ft. It doesn't confirm yet that the trailing edge sweep is correct, but at least some basic dimensions are correct.

Rob

My models:

I googled some more and found the source of the data: NACA TN-D3343 'Summary of full-scale lift and drag characteristics of the X-15 airplane', available as a PDF. It confirms the 14.91 and 2.98 ft chords, and a quarter chord sweep of 25.64 degrees. Using this data and the span, I calculated a leading edge sweep of 36.76 degrees and a trailing edge sweep of 17.76 degrees. The Monogram X-15's angles agree within half a degree, more than good enough for me. Case closed. Thanks for the help!

Rob

My models:

Amazing what you can find with Google! I simply Googled for 'north american x-15 wingtip chord'.