Abstract: A data processing method and a computer based data processing system for use in providing, or optimising, an industrial procedure for generating a product. The system comprising digital processing means, and digital storage means. The storage means having a database stored therein comprising (a) data defining generic product descriptions in terms of physical and/or functional elements and associated properties; b) data defined a plurality of generic process descriptions in terms of process activities, activity sequence, and associated process capabilities, at least one of said generic process descriptions including an iterative set of process activities, and; c) data defining rules relating to a) and b). The method comprising providing the system with specific product information for the product.

Abstract: A control system for a gas turbine engine guards the engine against destructive overspeed resulting from failure of electronic components in the system due to overheating. A main electronic (preferably digital) controller is normally in control of fuel flow to the engine by means of a flow metering unit. In addition, an electronic overspeed limiter guards against overspeed at normal system temperatures, should the main controller fail, by overriding the action of the main controller on the flow metering unit. A failsafe unit is responsive to the temperature of the control system, and comprises components rated at a substantially higher peak operating temperature than the components used in the other units. The failsafe unit acts as an ultra-reliable switch operative to depower the main controller, and, optionally, the overspeed limiter, when the temperature of the control system exceeds a predetermined value above which components in the two latter units are likely to fail.

Abstract: For flight safety reasons in gas turbine aeroengines it is desireable that in the event of malfunction of an electronic control system--such as a fuel control system--caused, for example, by overheating due to fire, the control system should protect the engine and the aircraft against the consequences of such a malfunction. In the present invention this is achieved by arranging that the control system is provided with a failsafe unit which monitors the condition of the control system and puts the engine into a failsafe control mode if a control system condition signal generated by the failsafe unit varies beyond a predetermined limit. Thus, to ensure safety under overheating conditions, the control system condition signal is representative of the temperature experienced by the fuel control system and the failsafe control mode is a speed-limiting control mode.