Two similar tapered sweptback plan forms with the same two spanwise variations of twist have been tested in the Mach number range from 0.8 to 2.0. The test results showed, in general, rather good agreement with theoretical predictions of the incremental span loadings due to twist for zero angle of attack. The measured incremental span loadings due to twist generally diminished with increasing angle of attack through the Mach number range. At a Mach number of 0.9, the incremental loadings progressively vanished from the tip inboard with increasing angle of attack. For the highest angles of attack (about 20 degrees) at Mach number 0.9, there was no difference in the span loadings of the flat and twisted wings. At a higher supersonic speeds, a similar vanishing at the tips of the incremental loading due to twist was starting at the highest angles of attack (near 20 degrees).