Curtiss 82 / SO3C Seamew
Curtiss SO3C Seamew
In 1937 the United States Navy was looking for a replacement aircraft for its Curtiss SOC Seagull series of biplane floatplane aircraft. The USN wanted a more modern, monoplane that could fulfill the same floatplane reconnaissance role but also include better performance and could operate from both land and water bases as needed. The undercarriage wasmrequired to be interchangeable. Curtiss and Vought were invited to produce prototypes through a May 1938 contract. The Curtiss prototype designated XSO3C-1 and the Vought XSO2U-1. The XSO3C-1 first flew on October 6th, 1939 and Curtiss receiced an order for production after some design revisions were ordered by the USN (including larger tail surfaces and upturned wingtips to aid in stability). The revised Curtiss Model 82A became the USN SO3C-1 for production under the early nickname of "Seagull". The chosen powerplant became the 388kW Ranger V-770-6 series engine.
The SO3C fuselage sat atop a large centralized float running nearly the length of the aircraft while each wing underside was supported by smaller stabilizing floats fitted to struts. The pilot sat immediately behind the engine and the second crewmember, the designated observer (seated facing forward), was in a separate cockpit towards the rear of the aircraft, his position at the base of the vertical tail fin. Wings were mid-mounted and straight along the leading edge and tapered at the trailing edge, clipped at their tips (with a noticeable upturn to each tip end, needed to counter some initial instability problems in the prototype design). The empennage was dominated by a large vertical tail fin curved to provide the SO3C a most identifiable appearance. Horizontal stabilizers were fitted to either side of the vertical tail fin base. Construction was of all-metal, with the exception being the fabric-covered control surfaces.
Power was a Ranger XV-770-8 inverted V12 engine of 600 horsepower. The engine provided a listed top speed of 172 miles per hour though cruising was limited to around 123 miles per hour. Range was roughly 1,150 miles (or about eight hours of flight time) and the service ceiling was limited to 15,800 feet. The SO3C held an empty weight of 4,284lbs with a maximum take-off weight equal to 5,729lbs.
The SO3C carried a single 0.30 caliber fixed, forward-firing M1919 Browning machine gun (operated by the
pilot) and a 0.50 caliber Browning M2 heavy machine gun in the rear cockpit (operated by the observer). The SO3C could make use of a pair of 100lb general purpose bombs or 325lb depth charges, held externally underwing or on a central bomb rack. If fitted, the central bomb rack could field a single 500lb general purpose bomb.
The SO3C first flew in 1939 and was officially introduced for service in 1942. Users were limited to the United States Navy and the British Royal Navy (RN) Fleet Air Arm (FAA).
The first SO3C-1 "Seagull" production models were received by the USN in July of 1942 and served aboard the USS Cleveland with their V-770-6 series engines. The performance of these was never truly up to the expected USN performance standards and the type was subsequently generally converted to radio-controlled target drones under the designation SO3C-1K. All SO3C-1s were removed as front-line service, by the USN, by the time the SO3C-2C production models became available.
The SO3C-2 was based on the Curtiss Model 82B and was perceived as a more "navalized" form complete with arrestor gear and an under fuselage bomb rack on the landplane version to mount a 227kg bomb. 456 SO3C-2s were ultimately produced though 250 of these were sent to the UK under Lend-Lease under the designation of SO3C-1B (Curtiss Model 82C), although British records would seem to suggest that only 100 were received. However, these were ultimately delivered as SO3C-2C models featuring an uprated powerplant, hydraulic brakes for aircraft with wheeled landing gear and other improvements.
The Royal Navy Fleet Air Arm utilized the SO3C as the Seamew Mk.I. When the newer SO3C-2C versions came online with the Royal Navy, these were simply designated as the "Seamew 1". All of the British Seamews were relegated to general training elements and specific air gunnery/radio training groups.
First Seamews were delivered to the Royal Navy in March of 1943. The first squadron fielding the Seamew became training 755 Squadron at Worthy Down (FN459), Hampshire, UK, in August of 1943. This squadron operated up until 1945. Two other training squadrons existed as the 744 and the 745 Squadrons based out of Nova Scotia, Canada.
In all, 250 Seamew aircraft were received by the British. Later deliveries were cancelled after the availability of the American Vought OS2U "Kingfisher" floatplanes increased by January of 1944. Once the Kingfisher gained more ground, the Seamew quickly disappeared from the Royal Navy by the beginning of 1945.
The "Queen Seamew" was the FAA designation for the SO3C-1K target drone production variant of the SO3C series. Thirty such examples were ordered under Lend-Lease but the order was cancelled before delivery.
Curtiss attempted to revive the aircraft by introducing the SO3C-3 (Curtiss Model 82C). The SO3C-3 boasted a lighter operating weight with a more powerful engine in the form of the SGV-770-8 series. While promising, only 39 examples were completed before production ended in January 1944. Any existing orders were cancelled outright.
Plans to introduce an SO3C-3 variant with arrester gear, and production by the Ryan Aeronautical Corporation of SO3C-1s under the designation SOR-1, were cancelled. Some 795 SO3C were ultimately produced. The SO3C was deemed more-or-less obsolete by 1944 and retired completely from service by 1945.
Curtiss SO3C-2 Seamew
Engine: 1 x Ranger VX-770-8 inverted V12, 600 hp
Length: 36.84ft (11.23m)
Wingspan: 37.99ft (11.58m)
Wing area: 289.982 sq.ft / 26.94 sq.m
Wing loading: 19.68 lb/sq.ft / 96.0 kg/sq.m
Height: 14.99ft (4.57m)
Maximum Speed: 172mph (277kmh; 150kts)
Cruising speed : 109 kt / 201 km/h
Maximum Range: 1,150miles (1,851km)
Service Ceiling: 15,797ft (4,815m)
1 x 0.30 (7.62mm) caliber M1919 Browning machine gun in fixed, forward-firing position.
1 x 0.50 (12.7mm) caliber M2 Browning heavy machine gun in rear cockpit position.
2 x 100lb bombs OR 2 x 325lb depth charges underwing.
1 x 500lb on centerline bomb rack (land-based Seamews).
Empty Weight: 4,284lbs (1,943kg)
Maximum Take-Off Weight: 5,730lbs (2,599kg)
Engine: 1 x 447kW Ranger SGV-770-8 inline
Take-off weight: 2599 kg / 5730 lb
Empty weight: 1943 kg / 4284 lb
Wingspan: 11.58 m / 37 ft 12 in
Length: 11.23 m / 36 ft 10 in
Height: 4.57 m / 14 ft 12 in
Wing area: 26.94 sq.m / 289.98 sq ft
Max. speed: 277 km/h / 172 mph
Cruise speed: 201 km/h / 125 mph
Ceiling: 4815 m / 15800 ft
Range: 1851 km / 1150 miles
Armament: 1 x 7.62mm + 1 x 12.7mm machine-guns, 2 x 45kg bombs