31 July 2011 C1 CIVIL AVIATION DEPARTMENT HONG KONG ...

epair, modification and partial or complete overhaul.5 When a new type of aircraft fitted with a UK manufactured turbine engine is firstintroduced into service the operator is responsible for determining a 'typical flightcycle', described in engine terms, applicable to its operation. This should be done bysufficient monitoring of service flights, and as necessary training flights, to provide anadequate knowledge of actual engine flight profiles. If these appear to be in any waymore severe than those assumed by the engine manufacturer, the operator shall informthe engine manufacturer and the Director-General. Amended approved lives will bepublished if necessary.NOTES: (1) As differences between winter and summer operation, and differences in the installedposition of engine in the aircraft may make significant difference to the usageexperienced, these factors should be taken into account in the monitoring programmes.Also because autothrottle and auto-land systems can affect the envelope of enginespeeds used, it is important that any changes to the characteristics of such systems areassessed.(2) HKAR-1 Sub-section 1.5-3 requires the engine manufacturer to publish, in the enginemanuals, information concerning the engine flight profile assumed for the establishmentof safe lives.6 Each operator of an aircraft type (fitted with a UK engine) which he has not previouslyoperated shall, during the first six months of operation, establish that his engines arebeing used within the flight profile published by the engine manufacturer. If there isany reason to believe that the flight cyclic fatigue usage may be more adverse thancurrently assumed, the operator shall inform the engine manufacturer and the Director-General with a view to revision of the approved lives.7 The Director-General will, from time to time, review with UK engine manufacturers thetotal experience applicable to any engine/aircraft type. When this reaches a level atwhich the engine operation can be regarded as well established, the need forcompliance with paragraph 6 will cease, and this will be stated in the enginemanufacturers' manual material dealing with this subject.8 Additionally, all operators of UK manufactured engines will be required at yearlyintervals to make a formal statement that:-(a)(b)in respect of engines having been assessed under paragraph 6, there has been nochange to their operation, engine handling, auto-throttle systems, thrust reversedrills, etc.in respect of engines covered by paragraph 7, they are permitting no procedureswhich would result in their engines operating outside the prescribed flightprofile to an extent which could significantly affect fatigue life usage, unless anassessment by the engine manufacturer has shown any effect to be unimportantor allowed for by appropriate adjustment of lives.9 Operators of engines manufactured outside the UK may find that the enginemanufacturers' manuals contain different information on this subject from that in31 January 2002 AN-44 P.2