When given the opportunity to do something rare and extraordinary, seize it!
The photo above was taken in a friend's Nanchang CJ-6A aircraft while doing aerobatics over the Los Angeles coastline. How did I get this shot? First, I was lucky enough to have a friend who does this sort of thing as a hobby, and who kindly offered to take me up for a flight. Second, I planned very carefully for it. I visualized the sort of photos that I wanted to capture, and planned out the equipment and techniques that I'd need to capture each shot.
In a situation like this, my preference is to shoot wide - very wide. There's a lot going on up-close which gives context to the situation further away; it's important to capture both in order to get the feeling of adventure and excitement that you typically want in a photo like this. This applies equally to rain-forest zip-lining and racecars as it does to the cockpit of an aerobatic airplane. When you want the viewer to feel like they're part of the excitement in the photo, shoot wide!
In this case I used an Olympus E-PL2 m4/3 camera with a 9-18mm wide-angle lens. The pilot was more comfortable with the smaller and lighter Micro Four Thirds camera than he was with my large and heavy DSLR. If I were to lose hold of the camera while maneuvering, the DSLR could do much more damage to the canopy than the little Olympus. Since the light was good, there wasn't too much compromise in image quality due to the little camera's smaller sensor. In fact, the smaller sensor also gave me a bit more depth-of-field, which was important to get both the cockpit interior and the exterior ground in-focus. That 9-18mm lens offered a 90-degree horizontal field-of-view (equivalent to an 18mm lens on a 35mm full-frame sensor) - a rather wide lens indeed. The 18mm long-end of the lens was plenty enough to be able to zoom-in on the other Nanchang on our wing.
I set the camera up with a fairly narrow aperture to give good depth-of-field (f/8) and ensured fast shutter speeds by setting auto-ISO to adjust exposure for nothing less than 1/320. I set the AF system to use the center point, and used continuous shooting mode. It's difficult to carefully compose photos when pulling Gs in the back of an aerobatic aircraft, so I just did the best I could and clicked away several shots in burst mode during each maneuver. I think the results came out rather well.
Here's video footage from the flight, taken using several Go Pro HD Hero cameras: