23rd of August 1953
The Short SB.6 Seamew made its first flight on this day in 1953.
Design of the replacement for the Grumman Avenger AS 4 fleet of the Fleet Air Arm (Aviation component of the Royal Navy) started in 1951. After the design git accepted the order was given to built 2 prototypes, resulting in the first flight of aircraft XA209 in 1953. One of the requirements for the aircraft was that it would be able to operate on an aircraft carrier unassisted, another requirement was that the Royal Air Force would be able to operate the aircraft as a land-based aircraft.
The initial design had a Rolls Royce Merlin powerplant but for several reasons, the Nay wanted a turboprop, one of them being interference in the radar system by the ignition system of a piston engine. As the aircraft design specification called for a "simple" design, the aircraft was fitted with a non-retractable landing gear in a taildragger configuration. This configuration gave the radar a clear forward vision without interference. A nice feature of the landing gear system on the aircraft was that the landing gear could be jettisoned in case of ditching. The crew sat behind each other forward in the fuselage to provide good visibility in all phases of operation.
The handling characteristics of the aircraft were not the best, which led to extensive modifications of the prototype, some of them were;
Fixed leading edge slats were fitted
Trailing edge flaps modified with slots
This improved the handling characteristics of the aircraft, but the aircraft never became an "easy to fly" aircraft. Low-speed handling was an exception to the handling issues. Take-off, landing and crosswind handling were reported as simple and straightforward. The aircraft had a stall speed of 50 knots and lots of power reserve, as it only needed 50% power in level flight. Carrier trials were completed in December 1955 en 1956. After the Royal Air Force lost interest in the aircraft restructuring of the FLeet Air Arm let to a premature ending of the operational life of the Short Seamew. The final example was scrapped in 1967.
three versions of the Seamew were developed
SB.6 Seamew, 3 built Prototype
SB.6 Seamew, AS.1, 60 ordered initially, 24 completed Royal Navy version
SC.2 Seamew MR.2, 30 ordered, 4 built Royal Air Force version, modified to AS.1 standard
Specifications for a Shorts SB.6 Seamew AS.1; General characteristics
Length: 41 ft 0 in (12.50 m)
Wingspan: 55 ft 0 in (16.76 m) (23 ft 0 in (7.01 m) folded)
Height: 13 ft 5 in (4.09 m) (15 ft 7.5 in (4.76 m) with wings folded)
Wing area: 550 sq ft (51 m2)
Empty weight: 9,795 lb (4,443 kg)
Gross weight: 14,400 lb (6,532 kg)
Max takeoff weight: 15,000 lb (6,804 kg)
Powerplant: 1 × Armstrong Siddeley Mamba turboprop, 1,590 shp (1,190 kW)
Propellers: 4-bladed Rotol, 10 ft 0 in (3.05 m) diameter
Maximum speed: 236 mph (380 km/h, 205 kn)
Range: 750 mi (1,210 km, 650 nmi)
Endurance: 4 hr at 140 mph (120 kn; 230 km/h) and 5,000 ft (1,500 m)
Rate of climb: 1,600 ft/min (8.1 m/s) initial
Take off: 500 ft (150 m) at 69.9 kn (80.4 mph; 129.5 km/h) tas into 12 kn (14 mph; 22 km/h) wind
Hardpoints: 1,844 lb (836 kg) of weapons
Rockets: Several rockets carried underwing
4× depth charges
275-lb A/S bombs
20 28-lb Sonobuoys
ASV Mk. 19B radar (ARI 5838)