The Oxford was normally powered by a pair of Armstrong Siddeley Cheetah X air-cooled radial engines, capable of generating 340 hp. These were initially outfitted with wooden fixed-position de Havilland-built propellers, but had been designed from the onset to accommodate variable-pitch propellers when these became available. The starboard engine drives a hydraulic pump and air compressor, the former being used to actuate the undercarriage and flaps while the latter is used for the braking system; a vacuum pump is also present for the gyroscopic instrumentations. The port engine drives a 500-watt electrical generator. The engine cowling features an inlet that draws cooling air into a tank; a pair of tinned steel oil tanks are also contained within the cowling. Welded steel construction was used for the nacelles, which attach to the centre section of the wing at four separate rubber-insulated joints.