Rolls-Royce Griffon

Rolls-Royce Griffon. The Griffon was a powerful 37-litre V-12 aero engine developed by Rolls-Royce Limited during the Second World War. It was conceived as a larger, more powerful successor to the famous Rolls-Royce Merlin, intended to power a new generation of naval fighters and bombers. Entering service later in the conflict, the Griffon became the powerplant for several notable British aircraft, including late-mark Spitfires, the Fairey Firefly, and the post-war Avro Shackleton.

Design and development

The engine's origins trace back to the late 1930s, when the Air Ministry sought a more powerful engine for naval aircraft, leading to a design influenced by the company's experience with the Rolls-Royce R racing engine. Key figures like Ernest Hives and Arthur Rowledge oversaw a project that prioritized robustness and low-altitude power for Fleet Air Arm operations. Unlike the Rolls-Royce Merlin, it initially featured a single-stage supercharger, but later variants incorporated advanced two-stage, two-speed supercharger systems developed at Rolls-Royce Hillington. This evolution was driven by the demands of the Royal Air Force for better high-altitude performance in fighters contesting air superiority over Europe.

Operational history

The Griffon entered operational service in 1943, powering the Fairey Firefly fleet fighter and reconnaissance aircraft aboard carriers like HMS Implacable. Its most famous application was in later marks of the Supermarine Spitfire, such as the Spitfire XIV, which proved formidable against German threats like the Focke-Wulf Fw 190 and Messerschmitt Me 262 during the Normandy landings and the Operation Crossbow campaign against V-1 flying bomb sites. Post-war, the engine saw extensive service in the Avro Shackleton maritime patrol aircraft during the Cold War, and it powered racing aircraft like the Supermarine Spiteful and the Fairey Spearfish. The Griffon remained in Royal Air Force service with the Shackleton until the 1990s.

Variants

Numerous variants were produced to meet specific requirements. The early Griffon II and VI series powered the Fairey Firefly and Supermarine Seafang. The Griffon 61 series, with its two-stage supercharger, was crucial for high-altitude Spitfire variants like the Mk XIV. The Griffon 65, used in later Spitfires, featured a modified supercharger for improved medium-altitude performance. Other significant models included the Griffon 57 for the Fairey Barracuda, the Griffon 74 with a two-speed propeller for the Avro Shackleton MR.2, and the Griffon 58, which powered the Supermarine Spiteful. Each variant incorporated refinements from Rolls-Royce Barnoldswick and other production sites.

Applications

The primary application was the late-model Supermarine Spitfire, including the Mk XII, XIV, XVIII, and the naval Supermarine Seafire 45 and 46. The Fairey Firefly served as a dedicated carrier-based fighter and anti-submarine platform for the Fleet Air Arm. The Avro Shackleton was the engine's longest-serving platform, used for maritime patrol by the Royal Air Force, the South African Air Force, and briefly the Royal Australian Air Force. Other aircraft included the Fairey Barracuda torpedo bomber, the Boulton Paul Balliol trainer, the Supermarine Seagull, and the Fairey Spearfish prototype.

Specifications (Griffon 65)

* Type: 12-cylinder, 60-degree "V", liquid-cooled piston engine * Bore: 6.0 in (152 mm) * Stroke: 6.6 in (168 mm) * Displacement: 2,239 cu in (36.7 L) * Length: 82.2 in (2,088 mm) * Width: 30.8 in (782 mm) * Height: 44.8 in (1,138 mm) * Dry weight: 2,078 lb (943 kg) * Supercharger: Two-speed, two-stage centrifugal * Fuel system: Rolls-Royce Limited injection carburettor * Cooling system: Liquid-cooled, with ethylene glycol * Power output: 2,035 hp (1,517 kW) at 2,500 ft (760 m) with +18 psi boost * Specific power: 0.91 hp/cu in (41.3 kW/L)

Category:Aircraft engines Category:Rolls-Royce aircraft engines