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 The Slingsby Gull

 

In 1938 there appeared in British skies a small strutted sailplane which was known as the Slingsby Type 12 and named the Gull. It was only the third high performance sailplane that the firm had built, and the first to come out in any number. The Hjordis and King Kite, which were built respectively in 1935 and 1936, had been built for limited ownership, as very few pilots in Britain at that time were capable of flying them. The Gull represented a first attempt to build a sailplane with a good performance for that time which would allow the majority of pilots to break free from their training machines and their sites and make first attempts at cross-country flights. One should remember that gliding had only existed as a sport in Britain for about eight years. 

Prior to the arrival of the Gull, British pilots had had to rely on imported German sailplanes for high performance aircraft, and the fleet of these machines was quite limited: one Rhönadler, 4 Rhönbussard, one Rhönsperber, one Condor 2 and a Minimoa. As nine Gulls were built, it will be seen that the type became as numerous in Britain as all the foreign high performance sailplanes put together. One of the Gulls was exported to Australia before the war. Registered as VH-GHL, it carried out many pioneering flights over there and included among its pilots the famous Doctor Hayden. The aircraft still exists - on display in a small museum in Western Australia. 

Herman Kursawe of New York built A tenth Gull from Slingsby drawings in America during the war. It is still flying today under the registration N-41829 and is one of the jewels of the Vintage Soaring Association of America. Some of the Gulls in Britain became club high performance gliders, others were in private hands. The most famous among the latter was the "Blue Gull" which belonged to Geoffrey Stephenson and Donald Grieg at the London Gliding Club. Geoffrey is still with us, but Donald was killed during the World Gliding Championships in Switzerland when a cable cut a wing off his EoN Olympia.

 

 

The "Blue Gull" derived its name from the light blue paint scheme of its fuselage. Its wings were covered in transparent fabric. On 22nd April 1939, this glider became the first to cross the Channel from a height gained by natural lift. Before this, Kronfeld and Beardmore had crossed the Channel (in 1930) starting from great heights gained from aerotows. Geoffrey Stephenson started his flight with a 30Oft winch launch at Dunstable just before 3pm and ended in France at 5.35pm. The 210 km had been covered at an average speed of 80kph which was made possible by good thermal conditions and a tailwind of 45kph, gusting to 65kph on the ground. From this 30Oft launch, Geoffrey Stephenson rose rapidly to cloudbase at 400Oft (for those who do not know, combined hill lift and thermal lift at LGC can on some days be almost volcanic). From this height he set course east of London. After hesitating a moment before crossing the Thames because of the retrieve difficulties that would arise, he crossed the Medway at its widest point at 300Oft. After a cautious journey across Kent, he arrived at the coast near Hawkinge with only 100Oft in hand. Unexpectedly he encountered a strong thermal, which carried him up into cloud. When he left the cloud at 600Oft he was well out over the Channel. So far out that he decided he was more likely to teach France than England, given the tailwind that was pushing him on. Although only some fifteen miles away France must have seemed to him fifty miles away. It had previously been estimated that 800Oft was a safe height from which to cross the Channel. He thus set course for France via another cloud. This failed to give lift and in fact offered nothing but severe sink. Luckily, this sink decreased as he approached the coast and he was able to pass over the beach between Calais and Boulogne at 260Oft. He then headed inland to find a field large enough from which to be aerotowed home. He didn't quite make it and landed some ten miles inland near St.Omer. Ann Welch, then Ann Edmund, and Brian Powell came over with a trailer by Channel steamer. 


Fred Slingsby prepares for the Maiden Flight of the Gull

The "Blue Gull" thus found a secure place in Gliding History. Two small crossed British and French flags were painted on the side of its nose.

It is interesting to trace the "Blue Gull's" subsequent history. Registered as BGA 380, it spent the war in storage at Lever's Farm near Woburn, and thereby escaped the fate of most other gliders which were impressed for military service, or, when they were found to be unsuitable for this, were delivered to Training Corps units which had little use for high performance sailplanes. 

On 22nd May 1945, Geoffrey Stephenson got the "Blue Gull" out and flew it illegally at Fairoaks Airfield. This action led to his being reprimanded. Civilian gliding was made illegal well after the war started, and it remained so long after the war ended. The "Blue Gull" returned to Dunstable on 6th January 1946 and was sold to Geoff Arnold on 15th May 1947. Its subsequent history is unknown to us, except that it was acquired by a RAFGSA club in the East of England, where it was painted silver with RAF roundels on the side of the fuselage. The "Blue Gull's11 civilian C of A expired in 1953. We have reason to believe that it was destroyed by "spinning in" whist flying at the RAF Fenlands Gliding Club during 1957. We are virtually certain that it was flown by F1t.Lt Allen as competitor No. 30 in league 2 at the 1957 National Championships at Lasham, and this would confirm that the glider existed in that year. 

Update from Peter Purdie:

"The Blue Gull, (by then orange fuselage, white wings), was spun in by Terry Slack at the Fenland RAFGSA club at Feltwell on 10th August 1965. I watched him do it (and visited him in RAF Hospital Ely shortly after, once they had plastered his broken legs). Its C. of G was somewhat suspect, and its handling very odd. Stew Mead (then CFI of Fenland GSA) flew it on air display days at the 1965 World Campionships at Suoth Cerney.

The wreckage was acquired and rebuilt"

We now come to another Gull, BGA 378, which is the property of our member Tony Smallwood. This glider has made two 30Okm flights in its life, the last one earning Tony a first place at the 1980 Competition Enterprise. Tony, who is an airline pilot, had almost won the previous Competition Enterprise flying BGA 378. 

After the war, this aircraft had been owned by the Derby and Lancs Gliding Club and was at that time in its original form, with the exception of a built-in landing wheel. Between 1960 and 1966, BGA 378 underwent a major rebuild in the hands of Dick Green. It had already gone through some major reconstruction in 1954 by Peter Fletcher. During the second rebuild, BGA 378 received some of the components of the legendary "Blue Gull". (What these were for sure we do not know, but they may have been the tailplane and the wing struts.) Tony maintains that the wings of BGA 378 are not matched. Could one of them therefore have come from the "Blue Gull"? It was probably during the 1954 rebuild that the nose was modified from the original clean contour to a stepped canopy which was then in vogue.

Something of the "Blue Gull" lives on in BGA 378, the last airworthy Gull 1 in Britain. However, we know that another one is to be found, at the Royal Scottish Museum in Edinburgh. This museum deserves to be congratulated for being the only one in Britain to exhibit a high performance sailplane. Its exhibit has military registration VW 912. The Merseyside Publication "British Gliders" indicates that this aircraft was BGA 379 and that it had received its first C of A in October 1938. After the war it had been registered as G~ALPA and went to the RAFGSA in 1953. We believe that members of the Scottish Gliding Union who were flying from a site near Edinburgh had originally owned it.

 

"British Gliders" traces the history of all the Gull 1's:

  • BGA 334          Wks No. 293A  First C of A 4/38. Went to Australia, later registered VH-GHL. In a Perth museum.This was the prototype, first owner Dudley Hiscox.
  • BGA 348          Wks No. 301A  First C of A 6/38. Fate unknown.
  • BGA 349          Wks No. 302A  First C of A 6/38. Crashed 30/05/39 in an aerotowing accident at Welmburn.
  • BGA 350          Wks No. 303A  First C of A 6,/38. Crashed 5/04/39 at Walsall.
  • BCA 353          Wks No. 304A First C of A 6/38. Crashed 4/10/62 at Ballykelly, Northern Ireland. Registered post-war as G-ALMI in England.
  • BGA 377          Wks No. 311A2            First C of A 10/38. Fate unknown.
  • BGA 378          Wks No. 311A  First C of A 9/38. Registered post-war as G-ALPJ. Currently airworthy and. owned by Tony Smallwood.
  • BGA 379          Wks No. 316A  First C of A 10/3C. Registered post-war as G-ALPA. Went to RAFGSA 1953. Displayed at the Royal Scottish Museum.
  • BGA 380          Wks No. 320    First C of A 12/38. This was Stephenson's "Blue Gull". It was registered G-ALLC after the war. Its C of A expired in September 1953. It   was probably crashed by the RAFGSA in 1957.

 

The Design.
  • It has been said that Slingsby Sailplanes before the war were nearly all copies of German types, or at least bore a strong German influence. The first designs dating from 1931 were indeed German types. It is far safer to build and fly proven types than to design and build something new that would almost certainly entail development costs. What designer is not influenced by previous successful designs? However, young designers eventually came to Slingsby Sailplanes. With much individual encouragement and moral support from the BGA they were given a chance to try something new in order to put British pilots to the fore. 

Unfortunately, the Hjordis of 1935 and the King Kite of 1936 were not successful designs, and were hardly the machines needed for teaching British pilots to fly cross-country and compete successfully in international contests. Both machines were original designs embodying too many new ideas. However, it was already an achievement that they were almost good. 

In 1937, Fred Slingsby began to design a high performance glider himself, using many ideas from proven designs of the past, but also using one or two exciting ideas belonging to the future. The wings were to be kept light as well as their fittings. This required the use of wing-fuselage struts. The wing was going to be more economical than the Rhönadler's because the ribs inboard of the aileron were to be of equal chord, thus enabling their construction on the same jig. In late 1937, the original Type 12 was called the "Superkite" and had a King Kite tailplane. That same year Fred Slingsby visited the Wasserkuppe International Contest and admired the first Reiher. The Gull's nose thus adopted a profile like the Reiher's. Although we are guessing here, it is probable that he also noticed the Reiher's G6ttingen 549 wing profile. This had never been used on sailplanes before and no details had been published then. Fred could well have decided to use what he took to be a similar profile in his new design. Details of the NACA 4416 had been released. This was not nearly as fast as the profile used on the King Kite, but it would be much safer to use. Something similar to what was being used on the fantastic Reiher was deemed to be good enough for Slingsby's Gull. 

The prototype Gull 1 first flew in April 1938. Its price was quoted at an incredibly low £188 when all other high performance gliders were selling at well over £250. 

Dudley Hiscox owned this first Gull. Subsequent Gull 1s had an extended cockpit clear vision panel. Despite the probable influence of German sailplane designs, we believe that the Gull was one of the more original Slingsby designs of the 1930s.

Gull 1 - N41829 information

The images above can be downloaded in this zip file This excellent pdf was produced by RcSoaring Digest and conatains much information on N41829. Download here

 

The Gull 3

 

The Gull 3 deserves to be mentioned in connection with the Gull 1 as it is similar in almost every respect with the exception of an absence of struts and a longer and deeper nose. The cantilever wing meant that, to ensure sufficient strength, it had to be heavier than the wings of the Gull 1. But the end result was a slightly lighter and more efficient sailplane. The original Gull 1 was not fitted with airbrakes or spoilers, but the Gull 3 had upper surface wing spoilers. The Gull l's shortcomings were rectified with a resulting aircraft that handled extremely well and whose performance was at least as good as an Olympia. The only Gull 3 to be built by Slingsby had its first flight in 1940. Because of the war, its C of A was not issued until January 1941 although it had been built during 1939/40. The aircraft was so good that Fred Slingsby originally intended to put it into production after the war. However, the tight economic situation prevailing at that time did not allow the economic production of a pre-war design. The Gull 3 was therefore replaced by the Gull 4, a machine that was popular at the time when the Weihe and the Meise were becoming known by the British gliding community. Prince Bira of Siam, who was at the time the World Motor racing Champion, bought the Gull 3 in 1944 and flew it in the company of his dog, a small white West Highland Terrier called "Titch", on many epic flights, including one to 1200Oft, before he purchased Philip Wills' Minimoa in early 1946. The Gull 3 was later bought by a syndicate at the Oxford Gliding Club operating out of Weston on the Green. 

After a long rebuild, it was finally flown again in 1973. Its C of A expired again in July 1974 because its wing had been damaged by damp (casein glue failure) during the previous winter when it had been left out in its closed trailer at St. Mary's Farm, Clifton, near Deddington, Oxon. This glider with BGA No.643 was almost certainly the best high performance glider to be built in Britain before the war. It was superbly restored by the late Mike Beach, and is currently airworthy. Forty years after the first flight of the only prototype, Mike Garnett began to build one in his garden shed. Sadly he was not to complete the work, but a group of dedicated restorers based at the Blackpool and Fylde Club succeeded in bringing the project to fruition. There are now two airworthy examples of the type.                       

Price Bira's Gull 3 at the Brooklands Museum

You can download a zip archive of early photos of this Gull 3 shown below in thumbnail size

In the early 1980’sit a replica Gull 3was built with the cooperation of some of the Slingsby workers and finally finished off in the late 1990’s after Mike Garnett died during the construction of the glider. This glider is under further restoration and it is hoped that next year (2014) she will be back in the workshop for a recover with clear dope, and a new canopy and instrument panel. It will also include some cockpit modifications to give her a more vintage feel. (Pictures below).

DATA

 Empty Weight

Loaded WeightWing LoadingWing AreaMax L/D

Gull 1

172.5kg

283.5kg 

19.1kg/m 2

14.86 m 2

1:24

Gull 3

170.5kg

261.3kg 

17.57kg/m2

14.86 m 2

1:25

 

Both aircraft have the same 15.33m wingspan and the same NACA 4416 wing profile at root, RAF 34 modified at tip.

 (Click the 3 view for larger picture)