A two-stage turbine drives the 10 stage all-axial
compressor, whilst a single-stage free power
turbine drives the load. The combustor is
annular. The Gnome differed from the T-58 in having a British developed fuel control system (
Lucas). Because an all-axial design is employed, the final stage compressor rotor blades are amongst the smallest ever manufactured. Normally, a small engine such as this would feature an axial/centrifugal or even a double
centrifugal compressor. The engine was the first developed with a full authority analogue computer,
de Havilland Propellers' own, as part of the fuel control system, specifically to anticipate helicopter power demand from pilot control inputs and to limit fuel flow during acceleration to prevent engine surge from occurring. The system developed relieved the helicopter pilot of the need to control rotor speed directly; it delivered constant rotor speed under varying rotor load. and in this way was the analogue forerunner of all subsequent
full authority digital engine control (FADEC) systems worldwide. ==Variants==