Aircraft jacks are important tools in the performance of inspections and routine maintenance on all types of aircraft. Aircraft jacks are required whenever the aircraft needs to be fully or partially lifted off of the ground, such as performing maintenance on the tires or wheel housings, landing gear tests and when weighing an aircraft.
It is critical that the aircraft jacks are properly inspected and maintained and used according to established procedures. Extensive and costly damage could be done to the aircraft and serious injuries to maintenance personnel could result if the jacks are not handled properly and the aircraft slips off the jacks.
The maintenance organization should always have safety policies and procedures in place when using aircraft jacks and all maintenance technicians should be fully trained on those procedures before operating the aircraft jacks. Below are some of the common guidelines that need to be followed when using aircraft jacks.
First, the maintenance technicians must be trained in the general operation of the aircraft jacks and they must always be used within their design specifications and load limits. Each different jack and aircraft manufacturer will have detailed information on the proper use of their equipment so the appropriate manufacturer manuals should be read before the jack setup begins and they should be available at the site to reference if needed. Technicians should wear all required safety devices, such as safety glasses and gloves while operating the jacks.
It should be verified that all 90-day and 12-month maintenance inspections on the jacks have been performed along with the appropriate annual load test and that the proper documentation is available. An inspection should also be performed just prior to using the jacks to ensure that they are fit for use. If the jack does not pass this inspection, it should not be used until the proper repairs can be made, or significant damage could occur. That inspection consists of:
The aircraft jacks should only be used on a solid, level surface. The jacks and aircraft should be protected from any adverse weather and wind conditions during the jacking procedure. When possible, an aircraft hangar provides the best environment for jacking an aircraft.
Before jacking up the aircraft, the areas under and around the aircraft should be examined to determine if any safety risks to the aircraft or personnel are present. The immediate area around the aircraft should be secured and identified with safety barriers or warning notices. During the jacking procedure, no additional work should be performed or personnel be allowed on the aircraft.
The proper location of the jack points for the aircraft should be located. The manufacturer’s maintenance manual will provide the location information for each type of aircraft. The jacking points are usually placed equally around the aircraft’s center of gravity so the aircraft will be balanced when lifted on the jacks Three jacking points are usually used, one on each wing and one on the fuselage near either the tail or the nose of the aircraft. The correct jack pad for the aircraft type should be used to ensure that the aircraft load is properly distributed and to assist in the centering of the aircraft jacks underneath the jack point.
When the aircraft is finally ready to be raised, the jacks need to be operated simultaneously to keep the aircraft as level as possible and to avoid any tilting of the aircraft which could overload one of the jacks. A crew leader can be positioned at the front of the aircraft to give instructions to each of the technicians manning the jacks. The aircraft should not be raised any higher than is necessary to accomplish the job required so that the jacks remain below their safety lift range.
By following the established safety procedures and performing the proper maintenance on the aircraft jacks, serious accidents and damage can be avoided and all aircraft maintenance can be performed in a safe manner.
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