AIRCRAFT MAINTENANCE

MAINTENANCE

Details of the operations necessary for the inspection and maintenance of pressurisation system components will be found in the relevant Aircraft Maintenance Manuals and Approved Maintenance Schedules, and reference must at all times be made to such documents. The information given in the following paragraphs is intended only as a general guide to the checks normally required on the principal components covered in this literature.

Pressure Controllers

Functioning tests of the pressure controller, should be made when defective operation of the pressurisation control system is suspected, and at all other times specified in the relevant Approved Maintenance Schedule. Further checks can be carried out where electronic pressure controllers are equipped with Built In Test Equipment (BITE). Adjustments and rectifications which may be made in situ are limited, and therefore the relevant Aircraft Maintenance Manuals appropriate to the type of aircraft and controller should be referred to before any adjustments or tests are carried out. If the results of the functioning tests are unsatisfactory and the pressure controller is found to be defective, it should be removed from the aircraft and tested according to the manufacturer's recommended test schedule and as appropriate, repaired, overhauled or replaced.

At certain specified intervals, some pneumatic pressure controllers are required to be lightly lubricated using only lubricants recommended by the manufacturers. Checks should also be made for security, corrosion or damage, and the associated electrical circuits should be tested as necessary for continuity and insulation resistance.