No, not a composite. I'm not that good with PS. Wait 'til you see my Red Arrows shot I'm hoping to put up by tomorrow. A large slice of luck came my way.
As for prop blur it was challenging figuring out how slow I needed to go for all the different types of aircraft. The light was changable but mostly dull, so I'm not sure how much was down to light and how much was down to different prop speeds but it really varied.
If this is not a composite of two separate passes, then this is indeed pretty crazy! Your angle was excellent and (as you commented to me) it is so refreshing to see aircraft in-flight pictures where the photographer didn't simply dial up the shutter speed to 1/2000 a fire away, knowing the image thus produced would be sharp. You used a shutter speed that would result in a nice propellor blur, making the panning of the subject more critical, but worth it in the overall great results you achieved!
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