As the age of the jet fighter was getting its feet underneath, longtime fighter supplier Grumman approached the United States Navy (USN) with a concept for a new carrier-based solution which came to be known as the "Sapphire Cougar" for its lineage related to the earlier F9F "Cougar" and its choice of engine, the British Armstrong-Siddeley "Sapphire" turbojet. The engine was a local-license model from Curtiss-Wright which tagged it the "J65". The fighter was intended as a compact product to serve from the decks of the space-strapped Essex-class aircraft carriers then in USN service. As such it would have featured carrier-operation qualities like wing-folding, a reinforced under-structure, and arrestor hook equipment.
The aircraft certainly mimicked aspects of the F9F and the subsequent F11F "Tiger" developments put forth by the same company. A swept-back, high-mounted mainplane form was used as were side-mounted intakes. The pilot's position was well-forward in the design, positioned just over the nose. The tail section featured a single fin with a pair of horizontal planes - all featuring sweepback. A tricycle undercarriage rounded out the list of modern features.
It is assumed that the Sapphire Cougar would be outfitted with 4 x 20mm cannons to fulfill the fighter requirement. This would be consistent with carrier fighters of the late 1940s and early 1950s. The high-mounted wing mainplanes also opened the design to carrying underwing stores such as early-form Air-to-Air Missiles (AAMs), conventional drop bombs and rocket pods - the latter two offering an inherent strike capability and doubling the design's tactical usefulness.
The USN eventually showed little interest in the Sapphire Cougar concept and the design fell away to military aviation history in time. At least a wind tunnel model was completed for testing to go along with design drawings and this marked the Sapphire Cougar as a stepping point towards the upcoming F11F Tiger - which was adopted by the USN in useful numbers (200).
As the Sapphire Cougar was never built and flown, performance figures remained estimated by Grumman engineers as part of the USN proposal. This included a maximum speed of 725 miles per hour, a service ceiling up to 51,000 feet and a combat radius reaching 320 miles.
- X-Plane / Developmental
41.24 ft (12.57 m)
31.66 ft (9.65 m)
13.12 ft (4 m)
12,787 lb (5,800 kg)
15,807 lb (7,170 kg)
637 mph (1,025 kph; 553 kts)
51,001 feet (15,545 m; 9.66 miles)
652 miles (1,050 km; 567 nm)
13,400 ft/min (4,084 m/min)
4 x 20mm Colt Mk 12 cannons under the nose section.
4 x AIM-9 "Sidewinder" short-ranged Air-to-Air Missiles (AAMs) OR Aerial rocket packs OR 2 x Jettisonable fuel stores.
"Sapphire Cougar" - Named Proposal; not selected by the United States Navy for development.