The standard fixed overhaul fee typically covers the routine workscope, labour, tooling, consumables and the landing gear shop’s routine overhead. Additional items are costed separately including NR tasks, service bulletin (SB) tasks as well as any other requirements including airworthiness directives (ADs)
The life of an average aircraft’s landing gear is a hard one. The force of the landing gear hitting the runway upon landing is significant and whilst this is the job the landing gear is designed to do it stresses the entire system.
The Landing Gear includes a pressurized oleo-pneumatic shock-absorber which exerts stresses on the housings. Additionally, horizontal forces are exerted on the gear whenever the aircraft brakes or accelerates.
Towing adds strain to the landing gear in addition the landing gear can be damaged by inappropriate jacking and other forms of maintenance event mishandling.
Landing Gear like every other critical system on an aircraft, has its own vulnerabilities that have to be monitored and cared for. In this way it will contribute to keeping overhaul costs down.
During maintenance periods it is expected that defects will be found and typical techniques to support heavy landing gear maintenance can be very expensive including engineering, plating and machining, NDT painting & assembling; and bush manufacturing.
Aircraft Landing Gear Maintenance Best Practice
a) Exercise care when washing the gears pressure washing may cause problems, because it can allow water at pressure to enter into the bushings and joints, causing corrosion.”
b) Care with the use of Solvents – Certain solvents such as paint stripper can cause ‘hydrogen embrittlement’. What happens is that hydrogen interacts chemically with the high tensile steel in the gear, causing the affected areas to transform chemically into a brittle alloy with a risk of fracturing.
Pay attention to forbidden substances to avoid during landing gear maintenance and servicing and ensure this information is documented and shared with all maintenance personal.
Note – The only way to counteract hydrogen embrittlement is to remove the affected component and bake it in a special oven at 375 degrees F for many hours
c) Ensure correct lubrication is carried out in accordance with AMM requirements – insufficient lubrication causes unnecessary wear-and-tear in many of the system’s components.
Correct lubrication ensures proper function of the gears, as well as less friction and wear. Lubrication is also a key ingredient to keeping out water, de-icing fluid, and other corrosion-causing substances.
d) The original equipment manufacturer (OEM) component maintenance manuals (CMMs) provide guidance regarding what repairs may be carried out during overhaul and what parts require mandatory replacement.
Sofema Aviation Services www.sassofia.com offers EASA compliant regulatory training to cover Aircraft Landing Gear Engineering and Maintenance Management Considerations. For details please see or email office@sassofia.com
