• The Percival "Gull" G-ACGR of the Air & Space museum of Brussels
• The oldest flying Percival aeroplane and the world's last flyable example of its type.

Type history

The Percival Gull was an all-wood, low-wing cabin monoplane entered via a hinged roof and folding side. A Henderson patent cantilever mainplane was used, made to fold about the rear spar and provided with a small flap type air brake under the centre section.

The prototype, G-ABUR, powered by a Cirrus Hermes IV, was built at Yate by George Parnall and Company and flown round Britain by E. W. Percival in the King's Cup Race of July 8-9, 1932, at an average speed of 142-73 m.p.h.

In the following year, re-engined with a Napier javelin III, it had a top speed superior to many contemporary fighters, becoming well known at civil aerodromes until written off in Northern Rhodesia during Man Mohan Singh's 1935 Cape record attempt.

By virtue of its four cylinder Hermes IV, the prototype became the Percival Gull Four P.1. Mk. I, while production aircraft with improved windscreens and cabin glazing became known as the Gull Four P.1.A Mk. II.

Private owners, such as Sir Phillip Sassoon and W. Lindsay Everard, favoured the Percival Gull Four P.1.B Mk. IIa equipped with a Napier Javelin engine, like their respective G-ACGR and 'AL 'Leicestershire Fox' 182.

A Gipsy Major powered P.1.C Gull Four Mk. IIb as well as a Blackburn Cirrus major powered P.1.E Gull Four Mk. III were developed later.

Gull Fours satisfied a lively market and were sold as far as Brazil and Japan, and on December 10, 1933, Sir Charles Kingsford Smith arrived at Darwin, Australia in G-ACJV 'Miss Southern Cross' after a record-breaking flight from Heston in 7 days 4 hours and 44 minutes.

Three unsold Gulls, G-ACHA, 'PA' and 'XY', similarly modified and fitted with Gipsy Six engines, were in later years allotted the type number P.3.

G-ACGR history

G-ACGR was originally ordered by Sir Philip Sassoon, at the time Under-Secretary of State for Air of the United Kingdom.

Sir Philip had selected a Napier "Javelin 111" engine, air-cooled 6 cylinders in line, delivering a power of 160 bhp at 2.100 rpm and pulling the "Gull" to a maximum speed of 160 mph.

The interior furnishing of that particular aircraft was indeed fitting to its illustrious owner. Sir Philip had called for a 2 seater arrangement instead of the standard 3 seater and the gain of space allowed the installation of a comfortable club armchair. The pilot seat, the passenger's armchair and the side panels were covered with deep red leather, embossed with the trademark of Percival aircraft, a silhouette of a gull.

It competed in a number races in the colours of Sassoon: the King's Cup air race of 1933, at Hatfield, with Flying Officer G.R.A. Elsmie as pilot (racing number 17) and at the end of August 1933 in the Folkestone Aero Trophy Race (racing number 8) flew by F/Lt S. Hawtrey.

On 8 May 1934, G-ACGR's ownership was passed to Sir John Kirwan via Aircraft Exchange and Mart Ltd. of London. In the hands of Sir Kirwin, G-ACGR participated in the 1934 King's Cup (racing number 26, Pilot-Officer J.D. Kirwan) and in the London to Newcastle-upon- Tyne race.

On 12 October 1934, G-ACCR took-off for its last trip. Over Belgium, around 17.30 hours, near the village of Kerkhove the engine lost some power and the pilot elected to make a precautionary landing. It overshot on the attempted emergency landing and finished with its nose in a tributary of the Escaut river.

The day after, the aircraft was retrieved and left by road to England, via Ostend.

What happened next remains a mystery to this day. On 7 December 1934, G-ACGR was written off the official British register.

Since the damaged airframe was found in Belgium, it can be assumed the owners or the insurers elected not to ship it back to England, only recuperating the engine, propeller and instruments. The airframe must have been disposed off in some way, either selling it or giving it away to some interested party.

In any case the "Gull' disappeared for more than 35 years until 1973 when Mr. E. De Deurwaerder retrieved the aircraft wreck that was stored in a barn near Nieuport.

The "Gull" remains arrived in the museum in 1975 after being donated by Mr E. de Deurwaerder.

Sources

• Flight: July 8, 15, 29 1932, March 2, 30 1933, July 6 1933, October 19 1933, April 26 1934, November 21 1935
• The aeroplane: July 27 1932, March 1 1933, May 24 1933, July 5, 12 1933, July 11, 18 1934
• Correspondence with Edgar W. Percival, John Stroud and Roy Humphreys (Kent aviation historical & research society).
• De Standaard, maandag 15 oktober 1934.
• La Libre Belgique, 13 octobre 1934.
• Aeroplane monthly, January 1983, June 1994, July 1994
• Flying, August 1933

G-ACGR reborn

Once recovered, the overall condition of the aircraft was found to be pretty poor.

For a start, the Napier Javelin engine and the Fairey-Reed propeller were missing, and still are, as well as two thirds of the undercarriage. One of the main beam had been sawn, yet the cockpit, upholstered with leather survived in a fairly good state. The ribs of the centre section's leading and trailing edges were almost non-existent and, to crown it all, the tail surfaces had simply been sawn off.

Part of the cowling was also missing except the frontal and bottom elements. Also both wing and tail strearnlining fairings were gone.

The wings were still in a fairly good state but were deprived of all leading edge ribs, all the wing fairings were missing as well as the upper engine cowlings. The aircraft remained untouched for a while till 1978 when a small team led by Jean-François Neefs decided to proceed with its restoration.

Fuselage

As far as the woodwork is concerned we first rebuild the centre section, then repaired the lower left beam of the fuselage. After this we had to stick together the cockpit floor, which had come loose and clean the all structure. Reassembling the tailplane which had been sawn off on both sides of the fuselage was another tedious task.

Undercarriage

The left U/C leg was missing, whereas the right one was buckled and incomplete. We first straightened and completed the left U/C leg then redrew and tooled the 136 elements composing the right leg. A jig was manufactured and a professional welder spent about 50 hours welding the various components of the right U/C leg.

It is worth nothing that this type of undercarriage is very fragile and required a lot of skill of the pilot during landings. It was replaced by a much sturdier model on later Gulls.

Firewall

As the original bulkhead had been seriously damaged, we had to build a new one using the original as a template. The asbestos, which was still in a very good state, has been reused and placed between the two new bulkheads.

Engine & airscrew

The Napier engine, with which this aircraft was originally equipped, was missing and as far as we know there are no more of this type available in the world.

After we had checked the inventory of the Museum's engines we discovered a Gipsy Major 1, serial number 523, contemporary to the Gull. In 1933, Percival had been selling its "Gull" with a choice of engine, including, beside the "Javelin", the Gipsy Major». That led to the decision to install this engine but new bearers were required as the original where for the Napier Javelin.

Using the available documentation, we redrew and manufactured new bearers for the Gipsy.

The propeller, after much searching, had been found in England and its owner, Mr. Norman Torquill, informed of the restoration project had kindly donated it. Another missing item was the propeller spinner that had to be manufactured using the forward cone of a "Mirage V" underwing container as a base

Wings & tail unit

The wing structure, as a tribute to Basil Henderson original design, was basically intact and free of any distortion. However the leading edges were damaged, the plywood covering had been ripped off and many ribs were broken or had rotten away, more especially those of the mobile flaps giving access to the wing folding mechanism.

What was left of a few heads, of ribs and accurate measurements allowed the construction of templates from which new ribs were built. Once the outer wings were reconstituted, their wooden structure was lacquered and subsequently varnished. The ailerons were intact and only needed cleaning, varnishing and were recovered.

The two lifting flaps of the wing folding system had to be built on the basis of the few remaining struts and ribs. The woodwork terminated, the control cables were reinstalled and a new pitot tube was built.

The steel parts of the wing folding mechanism were missing and pieces from a Percival "Proctor" wreck were used after being be modified to fit the "Gull'. The fuel tanks, badly corroded, had to be treated and welded.

The tail unit, the fin and rudder needed very little work but the tailplane and elevators demanded major reconstruction. The missing ribs were replaced by new ones after reconstituting the original profile and making aluminium templates.

Fairing, wheel covers, hood, cowling

The missing fairing strips at the wings and tailplane roots were replaced by fairings from a "Proctor" wreck: although of slightly different measurements they could be adapted without modification.

Surprisingly the two wheel spats had survived with the wreck except for the rear part of one, the hind cone. The metal workshop of the Belgian Air Force's Technical School at Saffraenberg soon turned an exact duplicate.

The frame of the hood was severely corroded and the Plexiglas had twisted and blackened under the effects of heat and years of neglect. Made of a welded steel frame on which are screwed dozens of small aluminium gutters and profiles.

After months of stripping-off and polishing, we succeeded in saving a majority of the components.

Of the two saved cowling elements, front and ventral cowls, only the first could be saved from corrosion and re-used. Top and side cowls were made in-house from aluminium sheets.

The lower or ventral cowl, with intricate forms, was manufactured by the Establishments Alverez of Brussels using the existing but corroded one as a template.

Instrument Panel

Although the instrument panel was still in place, all dials and instruments had been taken away and replacements had to be found.

Half of them were found in the museum store and Cdr Desmond St-Cyrien gave the rest, the well know British collector who also procured a copy of the registration certificate.

Painting

Finished, the aircraft wears the colours scheme G-ACGR had during the 1933 King's Cup. The top part of the fuselage and the wings were painted pale blue while night blue was retained for the lower part of the fuselage and the wheel fairings. The registration markings were in reverse colours.

Many people have raised questions on the exact tones of colours since only black and white photos are available.

The decision has been made mainly because of the quote published in "Flight" of 31 August 1933 p. 872: " ... the Percival "Gull" owned and entered by Sir Philip Sassoon ... this is the same machine, with a magnificent pale blue finish, which was raced in this year's King's Cup race". Moreover the cover of the same issue, a Cellon advertisement, illustrates a colour drawing of G-ACGR . Also, a witness of that era, Mr. John Stroud, did approve the scheme of the restored aircraft and some sample colours, retrieved when working on the aircraft, tends to confirm the choice.

Epilogue

The lengthy restoration came finally to an end in 1992.

To celebrate the event, and the Gull was the first of the aircraft restored by the BAMRS to be so celebrated, we displayed the aircraft in the park surrounding the museum.

Without the goodwill, ingenuity and dedication of the members of the team, all volunteers, this aircraft would still be a pile of wrecks rooting away.

Sources

• Vintage aircraft number 25 and 36
• Air Britain digest, autumn 1990, summer 1991, autumn 1998
• Air Britain archive 1/91, 2/91, 9/91
• ASA newsletter, 1994
• Flypast, Aeroplane monthly, le fana de l'aviation, Aeronews of Belgium

The following article is just an extract (reproduced here with the permission of the Editor ) from the article "Percival Gull Four" by Graham Orphan, published in the November/December 1999 issue of the Classic Wings Downunder magazine.

All restoration pictures are from Dave McDonald, the in-flight one is credit to Craig Justo - Aero Aspects.

In 1979 the Queensland Vintage Aeroplane News announced that the Percival Gull Four VH-UTP had been recovered from New South Wales in derelict condition. A full restoration to flying condition was planned.

Twenty years later, a magnificent Gull Four, the world's last flyable example of its type, is airborne at last!

Our subject aeroplane, Percival Gull Four C/N D.30, was the 10th Gull built, joining the British Civil Aircraft register as G-ACHA on 17th June 1933 in the name of Edgar Percival who flew it in the Kings Cup race on the 8th of July.

Fitted with a Napier Javelin engine, the Gull was sold to Airwork Ltd. of Barton in August of that year, and after a short period in service, a de Havilland Gipsy Major was fitted in place of the original power plant. In this configuration the Gull was sold to Australia where it was registered VH-UTP on 9th June, 1935 to P.G. Taylor (later Sir Gordon Taylor) of Sydney, who's exploits as a pilot, navigator and writer are well known.

Ownership changed several time till 19th May 1956 when a ground loop at Bourke ended the flying career of VH-UTP the registration being cancelled on 30 June 1956 in the ownership of Rain Air Taxis.

Although damage was not extensive the old aircraft was obviously thought to be not worth repairing and came to be stored in a shed at Bargo, outside Sydney. There followed two decades of storage in other than ideal conditions before the beleaguered Gull was at last rescued and taken to Queensland for a planned restoration to flying condition.

The tide turns for the Gull

Don had originally envisioned carrying out much of the restoration work himself, but the opportunity to take a position with an overseas airline put raid to that idea a and the Gull remained stored for some time.

Eventually, it was decided that to get the restoration underway, it would be put in the care of Nick and Greg Challinor's Mothcair Aviation.

The project would necessarily progress on an 'on again-off again' basis subject to the variables of funds available, materials supply, other projects within Mothcair's hangars and so forth. Fortunately, at about the time the Gull entered Mothcair's workshops, Nick and Greg's father Peter had joined the company on a part time basis.

After 50 years, the thin plywood skins of the fuselage would naturally have to be replaced, but removing these then required the remaining structure to be closely scrutinised to determine what would be reusable in an aircraft that would hopefully last many more years as an active flying aircraft. The folks at Mothcair will always retain as much of the original materials useable, but not at the expense of safety, so common sense plays a large part in the decision made.

Peter proved more than equal to the task of blending the necessary new materials in with the original structure.

This process necessarily was spread avec many years such is the complex nature of the structure, particularly the wings, and Thankfully, almost ail of the original metal components, of which there is a surprising number, proved to be in quite good condition and these were carefully stripped, inspected, repaired where necessary and repainted ready for reinstallation.

The Gipsy major engine was overhauled to zero-time specs. In Mothcair's engine shop, and fitted with a new Invincible propeller. The hugely time consuming tasks of fabric covering, fitting interior systems, glazing, upholstery installation, cowling fabrication, painting etc. progressively occurred over several years.

The very last job completed on the aircraft was the construction of a new pair of the distinctive Gull Four spats. The originals had been removed from the aircraft long ago, probably when it was still flying actively.

Eventually Johnston gave the instruction to finish the aircraft which progressed steadily towards completion until, on 21st October, test pilot Steve Marchesi eased open the Gull's throttle for its first take off in 43 years. The flight went well, the engine fan smoothly, and all systems functioned, as they should.

Coincidentally, this momentous occasion took place precisely 10 years and one day after Don delivered the Gull to Mothcair. After a four-decade hiatus, Percival Gull Four VH-UTP has begun its second flying career.