Supermarine
Southampton

A world-class flying boat of its day with excellent reliability and good sea-keeping qualities.
Supermarine Southampton I prototype  N9896 The first Supermarine Southampton I N9896 on the slipway at Woolston.
 
The Vickers Supermarine Southampton reconnaissance flying boat was one of the most successful of such aircraft operated by the Royal Air Force (RAF). In addition to its intended duties, the type took part in many long-distance overseas flights leading to the development of overseas airways routes.
 
By the mid-twenties the RAF needed to replace their First World War vintage Felixstowe F3 flying boats and the civil Supermarine Swan was well received in its certification trials.  As a result, Vickers Supermarine received an order off the drawing board for six Vickers Supermarine Southampton flying boats (a military derivative of the Vickers Supermarine Swan) against Specification R.18/24. The first of these (N9896) was flown for the first time on 10th March 1925.
 
The Vickers Supermarine Southampton was a twin engine tractor biplane flying boat with diagonal (Warren truss) bracing of the wing centre section. The distinctive empennage featured three shapely fins and rudders. Power was provided by Napier Lion engines and in the first version, the Vickers Supermarine Southampton I, the hull and wings were of wooden construction. The crew comprised pilot and navigator / wireless operator and two gunners.
 
The type was an immediate success and a series of production orders followed, the final production figures being 83 production aircraft, plus a single example of the three-engine Vickers Supermarine Southampton X. A series of notable flights were undertaken by the RAF, including a 10,000 mile flight around the British Isles (a 7,000 mile flight to Egypt and back) and the flight to the Far East of four Vickers Supermarine Southampton IIs covering nearly 27,000 miles, including a circumnavigation of Australia.
 
Supermarine Southampton II N218 metal hull The Supermarine Southampton II with a metal hull was the main production version.
 
The first eighteen Vickers Supermarine Southampton aircraft delivered were Mk.Is, with wooden hulls. However, a research programme had convinced the Royal Air Force of the superior qualities of 'metal over wood' and so the final forty-eight were delivered as Vickers Supermarine Southampton Mk.IIs, with metal hulls. In a programme begun in 1929, all surviving wooden-hulled Vickers Supermarine Southamptons were re-built with metal hulls.
 
The metal hull is stated to have resulted in a direct weight saving of 540lb, with an additional benefit of avoiding water soakage, which could account for up to aa 400 lb weight growth of the wooden-hulled machines. The combination of this direct weight saving, with the resultant ability to carry additional fuel, allowed a maximum range of 900 miles for the vickers Supermarine Southampton II, compared with 600 miles for the Vickers Supermarine Southampton I.
 
Supermarine Southampton II N218 with Jupiter engines The first Southampton II N218 was also flown with Bristol Jupiter radial engines.
 
The first Vickers Supermarine Southampton II (N218) flew with Napier Lion engines, and later experimentally fitted with Bristol Jupiter engines. 24 new metal hulls were also built to be retro-fitted to the wooden-hulled Southampton I, and to act as spares.
 
Metal wings were also developed, offering a further 200 lb benefit in terms of weight saving. The metal winged aircraft were known as Vickers Supermarine Southampton Mk.IIIs.
 
The vickers Supermarine Southampton remained in RAF service until December 1936.
 
Supermarine Southampton I Argentine HB-1 HB-1 was the first of eight Southamptons purchased for use by the Argentine Navy.
 
The type was exported to Argentina, Japan, Turkey and Australia whilst 8 aircraft were sold also to Argentina, for use by their naval air arm. These aircraft were powered by two 450 hp Lorraine 12E engines, whilst of the 5 Argentine aircraft, 2 had wooden hulls and three were metal-hulled.
 
Two Ex-RAF Singapore I aircraft were sold to Australia (S1158, S1159 becoming A11-1 and A11-2, respectively) and these aircraft were intended to take part in the RAF Far East Flight’s circumnavigation of Australia. One aircraft (A11-1) was pre-positioned to greet the RAF Far East Flight at Adelaide SA in June 1928. Sadly however, a freak gust of wind overturned the aircraft as it was about to leave to meet up with the RAF flight.
 
Supermarine Southampton I RAAF A-11-2 The RAAF operated two ex-RAF Southamptons; A11-2 was previously S1159.
 
One Vickers Supermarine Southampton (A11-2) subsequently set off on a tour of the major cities of the eastern Australian States, an expedition which generated very positive publicity for the RAAF. Consequently, similar recruitment tours became a regular occurrence during 1929-33 period, with one of the aircraft undertaking such a task every six months or so.
 
In Australian service, the type proved to be very popular with aircrews due to the combination of a galley and sleeping area. It also found favour as a reliable, stable flying platform that earned high praise from those undertaking long range flights as well as those who maintained them.
 
The Vickers Supermarine Southampton main role was undertaking aerial surveys and long-range, search and rescue missions at sea. A secondary and almost unexpected usage was for aircrew parachute training.
 
Supermarine Southampton II for Japan The Supermarine Southampton sold to Japan was later converted for civil use as J-BAID.
 
The single Vicker Supermarine Southampton II sold to Japan in 1928 (J-BAID) was later converted to an 18-passenger civil configuration. 6 Vickers Supermarine Southampton II aircraft were also sold to Turkey, being deliveredas N3 to N8 under ‘Class B’ markings.
 
One Vickers Supermarine Southampton IV (S1648) was fitted with a 525 hp Rolls-Royce Kestrel III engine and this aircraft became the prototype for the Supermarine Scapa.
 
An aircraft known as the 'Southampton X' was created as a three engine sesquiplane (a biplane with one wing of less than half the area of the other). This all-metal flying boat had no connection to the original Vickers Supermarine Southampton other than the re-use of Southampton name. Whilst the hull was produced by Supermarine at Woolston, whilst the wings were the responsibility of Vickers Ltd at Weybridge. Both components markedly exceeded their planned structural weights (by some 30%).
 
Supermarine Southampton X N252 3 engine The one-off three-engine Supermarine Southampton X N252 was an unsuccessful development.
 
As a result, the sole example built (N252) proved to be underpowered when first tested in March 1930 and subsequently at the  Seaplane Experimental Station at Felixstowe. This led to a number of engine changes, with the initial Jaguar Vis being replaced by Bristol Jupiter XBFM / Bristol Jupiter XIF as well as Panther engines.

 

Specifications


                              
Southampton II
Southampton X
Powerplant
Two 500 hp Napier Lion VA
Three 570 hp Bristol Jupiter XFBM engines
Span
75 ft 0 in
79 ft 0 in
Maximum Weight
15,200 lb
23,000 lb
Capacity / armament
Five crew; provision to carry 1,100 lb bombs, three Lewis guns for self-defence. Provision for two externally-mounted 18-in torpedos.
Five crew and three 0.303 Lewis guns; 1,000 lb bomb load
Maximum Speed
95 mph
130 mph
Endurance / range
6.3 hr or 544 miles at 86 mph
1,000 miles at 100 mph

 

Variants and numbers built


Southampton I
Wooden hull and wings 18 for the RAF, two transferred to RAAF. Five built for Argentina.
Southampton II
Prototype N218, 48 for the RAF. Exported to Argentina (3), Japan (1), Turkey (6)
Southampton III
Southampton II with metal wing structure
Southampton IV
S1648 with Kestrel engines – became the prototype Supermarine Scapa
Southampton X
N252 Three-engine all-metal sesquiplane
Totals
25 Southampton I, 58 Southampton II, plus one Southampton X. Grand total 84 aircraft.

 

Survivors


Southampton I -
Hull only (N9899)
RAF Museum Hendon, London             
 

Other information