Co-ordination of hydraulic transmissions and aircraft A-C generators

IT HAS BEEN demonstrated in the past that hydraulic variable-input-speed constant-output-speed transmissions can fail under certain fault conditions. However, occurrences in flight with class A and class B systems have not been, to the authors´ knowledge, a major source of trouble. As shown in this paper, the possibility of drive failure is greatly increased in applications of class C systems. In fact, one such failure has reportedly occurred in flight. Hence it is essential to co-ordinate drive and electric system design to obtain the high electric system reliability required in modern aircraft. This paper presents a co-ordinated design on one system and introduces a general method for analysis which is sufficiently accurate to permit system design without extensive redesign of components after model testing has been completed.