Some of the unusual factors influencing the choice of digital computer control systems for jet engines are discussed first. The conditions differ in various practical respects from conventional process control applications. Having several identical plants in a typical aircraft and the need for flexibility to keep pace with engine development are of particular importance. Approaching digital control with the traditional process control background may be restrictive in selecting potential applications for the technique.

Techniques which can be used with computers to simplify and speed up three aspects of the realisation of a practical system are described briefly. The first of these is the measurement of the actual plant characteristics needed in the analysis of the control system requirements. The second is a method of obtaining good response in the synthesis of a non-linear control function. The third is a technique for programme writing and for simulation used in the verification of the control system behaviour.

The techniques described are not in themselves necessarily confined to use with digital control systems and should have value in general use.