AUTOMATION OF HAWKER BEECHCRAFT B200/B300 (KING AIR) AIRCRAFT - CARGO DOOR

The Hawker Beechcraft B200/B300 King Air aircraft is a twin engine turbo-prop aircraft with a pressurized cabin, normally capable of carrying 9 to 11 passengers.The aircraft can have a standard air-stair style access door or an optional larger 'cargo door', with a smaller air-stair within this cargo door.In either option the door is located on the left aft side of the fuselage, just aft of the wing.The larger cargo door generally to allow greater access to the cabin for aeromedical, freight or specialty roles.The 'cargo door' measures an opening of 52 by 52 inches (1321mm by 1321mm) and is hinged from its top edge.Operation of the 'cargo door' is carried out manually, by a single person assisted by two gas struts (not unlike those found on the lift-back on the back of a station wagon car).The door is safetied in the open position by a mechanical stay rod.The door is closed by the removal of the safety rod and pulling the cargo door down and into the aircraft fuselage, against the resistance of the two gas struts.The operation of this large and heavy door can place the operator in is an unsafe positions and requires a level of physical fitness and effort to, especially close the door.For this reason the operation of the door is generally avoided by operators unless absolutely needed and it has also created a number of workplace injuries such as strains, falls and slips.The operation of the air-stair door within the cargo door is also mechanical, but due to the air-stair door size and weight -its operation does not pose the same safety hazards.The engineering degree project developed an automated method of operating the cargo door, in the pre-existing cargo door installation.The design made consideration of the following:1. cost of the installation 2. aircraft down time for the installation 3. simplicity of the retrofit installation 4. consideration of the aircraft pre-existing structure and aircraft systems 5. minimizing additional weight to the aircraft installation 6. minimizing the 'new' mechanism interfering or consuming critical cabin space 7. aircraft certification requirements, and 8. provides for the operators health and safety needs.The automation retrofit design, was accomplished by the installation of an electrical motor, which applies it power is through a reduction gearbox, to actuate a rotary actuator and (radius) arm assembly.This, 'radius' arm controls the doors position though a slide track, affixed to the cargo door, which: extends, safeties when the cargo door open and retracts the cargo door closed.The design incorporates a self braking and position monitoring system, along with a manual method of door actuation, if there is no electrical power is available or the electric motor has failed.All of the cargo doors' original design features, including locking system, remain unaffected, except for the removal of the two side gas assist struts which are replace by this modification and (radius) arm assembly.