The Case for Pneumatics An Examination of the Possibilities of High and Low Pressure Systems

Abstract

THE outstanding difference in using a gas as compared with a liquid as a means of transmitting power is the high degree of compressibility which can be achieved in the one and its virtual absence in the other. As might be expected there are instances in both cases where the peculiar characteristic is of value and others in which it is a drawback. In some cases a soft damping action is required for which compressed air provides a suitable medium, while in others a high degree of damping at a controlled rate can best be performed by the use of hydraulic fluid. In applications where complete irreversibility is required by means of the locking of the medium in some restricted space air is virtually useless and in such cases recourse has to be made to some form of damping, either hydraulic or mechanical, which generally adds considerably to the complexity when compared with a straight hydraulic system. Also, in systems which call for small dead beat movements the consumption of compressed air is often unacceptable. On the other hand the medium itself does not constitute a fire risk, is readily replaced in flight in the case of small leakages and is responsible for quite a small expenditure in terms of engine power.

Citation

Wotton, J. (1958), "The Case for Pneumatics An Examination of the Possibilities of High and Low Pressure Systems", Aircraft Engineering and Aerospace Technology, Vol. 30 No. 7, pp. 190-198. https://doi.org/10.1108/eb032988