For the best handicam quality images, get a miniDV cam over hi8/digital 8. Resolution on hi8 isn't so hot versus miniDVs capture... but the size of the CCDs and lens quality are what you should look for.

Image stabilization is a good feature, but you'll need tons of zoom power to capture great airplane video... so you'll absolutely need a 2x extender for your lens. This will double your optical zoom length. Without the extender, framing RC planes nicely in frame will be very difficult.

A good fluid head tripod will allow you to get smooth shots. Armed with the 2x extender, the zoom will be great and camera movement (generated by hand-held) will translate into the frame... using a tripod will greatly influence the framing.

-Juhan