Jacks, Tow-Bars, GPU
Ground support equipment (GSE) is the support equipment found at an airport, usually on the apron, the servicing area by the terminal. This equipment is used to service the aircraft between flights. As the name suggests, ground support equipment is there to support the operations of aircraft whilst on the ground. The role of this equipment generally involves ground power operations, aircraft mobility, and cargo/passenger loading operations.
Many airlines subcontract ground handling to an airport or a handling agent, or even to another airline. Ground handling addresses the many service requirements of a passenger aircraft between the time it arrives at a terminal gate and the time it departs for its next flight. Speed, efficiency, and accuracy are important in ground handling services in order to minimize the turnaround time (the time during which the aircraft remains parked at the gate).
Small airlines sometimes subcontract maintenance to a larger carrier, as it may be a better alternative to setting up an independent maintenance base. Some airlines may enter into a Maintenance and Ground Support Agreement (MAGSA) with each other, which is used by airlines to assess costs for maintenance and support to aircraft.
Most ground services are not directly related to the actual flying of the aircraft, and instead involve other service tasks. Cabin services ensure passenger comfort and safety. They include such tasks as cleaning the passenger cabin and replenishment of on-board consumables or washable items such as soap, pillows, tissues, blankets, and magazines. Security checks are also made to make sure no threats have been left on the aircraft. Airport GSE comprises a diverse range of vehicles and equipment necessary to service aircraft during passenger and cargo loading and unloading, maintenance, and other ground-based operations. The wide range of activities associated with aircraft ground operations lead to an equally wide-ranging fleet of GSE. For example, activities undertaken during a typical aircraft gate period include: cargo loading and unloading, passenger loading and unloading, potable water storage, lavatory waste tank drainage, aircraft refueling, engine and fuselage examination and maintenance, and food and beverage catering. Airlines employ specially designed GSE to support all these operations. Moreover, electrical power and conditioned air are generally required throughout gate operational periods for both passenger and crew comfort and safety, and many times these services are also provided by GSE.
Chocks are used to prevent an aircraft from moving while parked at the gate or in a hangar. Chocks are placed in the front ('fore') and back ('aft') of the wheels of landing gear. They are made out of hard wood or hard rubber. Corporate safety guidelines in the US almost always specify that chocks must be used in a pair on the same wheel and they must be placed in physical contact with the wheel. Therefore, "chocks" are typically found in pairs connected by a segment of rope or cable. The word "chock" is also used as a verb, defined as the act of placing chocks in front and back of the wheel.
A ground power unit is a vehicle capable of supplying power to aircraft parked on the ground. Ground power units may also be built into the jetway, making it even easier to supply electrical power to aircraft. Many aircraft require 28 V of direct current and 115 V 400 Hz of alternating current. The electric energy is carried from a generator to a connection on the aircraft via 3 phase 4-wire insulated cable capable of handling 261 amps (90 kVA). These connectors are standard for all aircraft, as defined in ISO 6858.
A so-called "solid state unit" converts power from AC to DC along with current separation for aircraft power requirements. Solid state units can be supplied stationary, bridge-mounted or as a mobile unit.
They are used to support a parked aircraft to prevent their tail from drooping or even falling to the ground. When the passengers in the front get off an aircraft, the aircraft becomes tail heavy and the tail will droop. Using the jack is optional but not all aircraft need it. When needed, they are tugged to the tail and set up by manpower. Once set up, no supervision to the jack is needed until the aircraft is ready to leave.