4-6: Aircraft 
Skydivers play a more integral role in aircraft operations than ordinary passengers, because their procedures can dramatically affect the controllability of the aircraft, particularly during exit.
Parasitic drag reduces airspeed necessary for flight and reduces the effectiveness of control surfaces. Excess weight in the rear of the aircraft can cause the pilot to lose control of the aircraft and cause it to stall. A jump pilot should brief all jumpers on the topics outlined in Aircraft Briefing from Category E of the USPA Integrated Student Program. The smallest aircraft used for student jumping should be able to carry the pilot and at least three jumpers.
Those planning to open their parachute above the normal opening altitude (generally 5,000 feet AGL and lower) should inform the pilot and all jumpers on board, as well as any other jump in flight at the time.
Aircraft fueling operations should occur away from skydiver landing and loading areas, and no person, except the pilot and necessary fueling crew, should be aboard the aircraft during fueling. USPA accepts the practice of rapid refueling (fueling an aircraft while an engine is running) for certain turbine-powered aircraft when performed in accordance with the guidelines of Parachute Industry Association Technical Standard TS-122. Piston-powered aircraft should never be rapid-refueled.
Students should never approach an aircraft, whether the engine is running or not, unless they are under the direct supervision of a USPA instructional rating holder. Everyone should always approach a fixed-wing aircraft from behind the wing and always approach a helicopter from the front or the side, only after making eye contact with the pilot. Everyone should always protect their handles while entering the aircraft and follow procedures to avoid the accidental activation of any equipment.
On the ride to altitude, everyone on board the aircraft is subject to the seating requirements found in FAR 91.107 and the parachute requirements found in FAR 91.307. Everyone should have a thorough understanding and be prepared to take the appropriate actions in the event of an accidental activation of parachute equipment in the aircraft. Seatbelts should remain fastened and all hard helmets and other potential projectiles secured until the pilot notifies the jumpers that they may unfasten them. Students should sit still and move only when their instructor(s) or coach specifically directs them to do so. Jumpers should determine seating arrangements—which will vary according to the particular aircraft and the size and type of the load—in advance.
Failure to maintain proper weight and balance throughout the flight may result in loss of control of the aircraft. This means the load must be properly distributed in the aircraft to maintain balance in relation to the center of gravity, which is necessary for the aircraft to fly safely. The jumpers must cooperate fully with the pilot to keep the aircraft within its safe performance envelope throughout the entire flight. The aircraft must not carry more weight than the maximum allowed in the manufacturer’s operating manual.
Seatbelts/restraints should be stowed out of the way but never fastened together unless being worn. All pilots and other occupants of a jump aircraft must wear parachutes when required by the FAA.