METHOD OF ESTIMATION OF HELICOPTER TECHNICAL STATE Russian patent published in 2004 - IPC

FIELD: operation of helicopter equipment. SUBSTANCE: proposed method consists in noting duration of flights according to level of loading of structure, determination of relationship of individual loading of units and loading corresponding to standard combination of modes of flights, noting operating conditions and their effect on level of loading of units and determination of relationship of equivalent individual loading of units and loading corresponding to standard combination of flight modes. Proposed method includes also estimation of technical state of primary gearbox mechanisms for joint operation with two engines, flight with one engine and use of auto-rotation modes of main rotor by means of one overrunning clutches by 250-hour stages till accumulation of at least 3500 operating hours. Total operating hours at limited takeoff and nominal modes does not exceed 5% of total operating hours of primary gearbox and equivalent operating hours at limited and nominal modes does not exceed at least 3500 operating hours. Revolutions of main rotor shaft range from 92 to 94% at limited takeoff mode and from 93 to 97% at nominal mode. EFFECT: possibility of optimization; enhanced reliability. 3 dwg