got a tip, for those without a sophisticated SLR, to get pics as well exposed as this! it assumes your camera has a infinity focus setting, but thats about all you need. set the camera to infinity, point the camera at something like the grass and half press your shutter, this should lock the exposure setting on the camera. now follow the aircraft, through the view finder, but when pressing the shutter, continue the movement, sort of like panning. this should help avoid the dreaded shutter lag.
the explanation:
focus first, in truth most camera lenses don't need focused, just set to infinity, beyond 10 feet. so setting infinity should mean that you get sharp pictures, without the need to focus.
exposure, all cameras, old and new, assume that all light surfaces reflect 18% of the light that falls on them. so to get correct exposure, even in the trickiest conditions, all you need is something that reflects just about that, grass is the most common thing you find that does just that, make sure the grass is filling the metering zone/ viewfinder and wherever you point the camera, unless the light conditions are changing rapidly, you will get perfect exposure on your shots.