No combustion-engine powered vehicles are permitted. Sorry.
No human intervention is permitted once the competitor is on the course. Control from any ground-station equipment via wireless link is permitted.
Any wireless communications methods are permitted (e.g. Wifi, Bluetooth, XBee, 2.4GHz). However, we do expect all the competitors to co-operate with the judges to ensure EM compatibility between everybody.
Unlimited attempts are permitted, at any time during the competition. Competitors may fly whenever a flying slot becomes available. A slot is defined as no less than 2 meters from the nearest competitor on entering the course.
There is no limit on the vehicle configuration: fixed-wing, rotary, or hybrids are all permitted.
Deliberate or excessive bumping and ramming is discouraged. What is deliberate or excessive? You will know it, the judges will know it, and then they will red-flag you.