Tag Archives: ADEN 30 mm revolver cannon

5 April 1968

Flt-Lt. Pollock flies his Hawker Hunter through the Tower Bridge, 5 April 1968. Illustration by Flight Artworks.

Friday, 5 April 1968: Flight Lieutenant Alan Richard Pollock, No. 1 Squadron, Royal Air Force, based at RAF West Raynham, southwest of Fakenham, Norfolk, was leading a flight of four Hawker Hunter FGA.9 close air support fighters. Pollock described the weather:

“Over London the weather was still one of those rare perfect 8/8 Gordon’s crystal, gin clear days when all the colours shout out brightly.”

Pollock broke away from the formation and flew toward London.

FLIGHT International reported:

Hunter to Tower—Under

     An RAF Hunter few through the Tower Bridge, London, in a down-river direction just after noon last Friday, April 5. The Hunter, carrying underwing tanks, was glimpsed momentarily from Flight‘s offices in a descending, mushing turn until lost to sight behind United Africa House. Previous flights through Tower Bridge—never in a jet, and never so fast—have invariably been made in an up-river direction.

     The MoD was investigating as we closed for press; the supposition was that the aircraft was an FGA.9 of 1 or 54 Squadrons, which comprise the close-support wing at RAF West Raynham. The station refused comment, but flying was taking place that day. Visibility was excellent. Some authorities attributed the incident to widespread resentment that the RAF had been deprived of a ceremonial fly-past on the 50th anniversary day, April 1. The Red Arrows were expecting to make this fly-past last month, but permission was presumably denied. A Ministry of Defence spokesman to whom we were referred at press time by the duty officer at RAF West Raynham, was not then able to reveal the name of the pilot.

FLIGHT International, Vol. 93, Number 3083, 11 April 1968, at Page 500, Column 3

Diagram of Tower Bridge, with dimensions. (Wikipedia)

. . . and the following week:

The Man Who Shot the Bridge

     The RAF pilot who flew a Hunter FGA.9 through Tower Bridge, London, on April 5 was no youthful prankster but a senior flight commander of 1 Sqn, RAF West Raynham, an Old Cranwellian, and the father of four children.

     He was Flt Lt Alan Richard Pollock, aged 32. He was named on Sunday, April 7, by MoD (Air) too late, owing to Easter press schedules, for mention in our last week’s story. Flt Lt Pollock was placed under close arrest on April 5 and released into open arrest on April 7. A board of inquiry was convened at West Raynham on April 8. An all-party motion signed by six MPs [Members of Parliament] was tabled in the Commons in his support but was ruled unacceptable.

     Whatever their views on the responsibility and possible consequences of flying a jet fighter through the 200ft-wide, 110ft-deep aperture framed by the towers, the bascules and the upper span of Tower Bridge, there is unanimity among pilots that it was a handsome piece of flying.

     Flt Lt Pollock was the first pilot to fly through the bridge in a downstream direction, following the gentle sinuousities of King’s Reach from the Waterloo Bend—and passing over Blackfriars’ two bridges (road and rail), Southwark Bridge, Cannon Street rail bridge, and London Bridge. After clearing the last he probably had little more than five seconds to align himself with the eye of the needle presented by Tower Bridge, retaining until the last fraction of a second the option of pulling up had he found the opening partly obstructed by abnormally high vehicles, by hanging cradles or by the bascules opening.

     It has been reported that Flt Lt Pollock peeled off from a formation returning from RAF Tangmere, where he had led four Hunters on display duties. This might have accounted for his choice of direction. The absence of pre-placed photographers, who always seem to have been around on previous Tower Bridge buzzings, seems to rule out premeditation. Another explanation of why he preferred the crane-lined Upper Pool downstream of Tower Bridge for his climb-out when all previous pilots have used it for the run in may have been to avoid climbing through the flight levels occupied by airliners on the approach to Heathrow had he made a westerly climb-out. He turned to port over the City.

     The RAF and civil authorities were tussling last week about whether Flt Lt Pollock should be court-martialled or tried in a civil court. His one-man fly-past was construed in and outside the RAF as an expression of resentment felt by many in the Service—including those now responsible for deciding his punishment—of the way the Royal Air Force is being treated by the Government. It may be that the last straw was the cancellation of the 50th anniversary fly-past over the capital on April 1. A fly-past planned in conjunction with the Lancaster House dinner with the Queen was cancelled at the last moment as “inappropriate.” A mid-day fly-past, seen by the maximum number of Londoners and visitors, would have been most “appropriate” on this occasion.

     Attitudes to the Tower Bridge exploit of past and present members of the RAF whom we have questioned vary from the very strongly censorious to the frankly admiring; but an unvarying theme was that some RAF protest was called for, without infringing flying discipline.

FLIGHT International, Volume 93, Number 3084, 18 April 1968 at Page 567, Columns 1 and 2

The Royal Air Force did not court-martial Flight Lieutenant Pollack. A medical board discharged him from the service. The Ministry of Defence announced that Pollack had been hospitalized with pneumonia, and that, “. . . if he were brought to trial it would probably have a damaging effect on his health, both immediately and in the long term.”

An oral history recording with Alan Pollack (32 minutes, 20 seconds) is available at the Imperial War Museum:


This was not the first time an airplane had flown through Tower Bridge. On 10 August 1912, Frank McLean (later, Lieutenant Colonel Sir Francis Kennedy McLean, A.F.C.) flew his modified Short S.33 float plane, and, according to his obituary in The Times, 12 August 1955, “. . . created a record by flying up the Thames in a seaplane, passing between the upper and lower parts of Tower Bridge and under London Bridge without touching the water.”

Frank McLean flying through the Tower Bridge, 10 August 1912. (Clan Maclean)

Alan Pollock was flying a Hawker Hunter FGA.9, XF442, c/n S4/U/3318. It had been converted from a Hunter F.6 interceptor. The Hunter was a single-seat, single-engine, swept-wing jet fighter, which first entered service with the Royal Air Force in 1954. The FGA.9 ground attack variant was based on the Hunter F.6 interceptor.

Hawker Hunter FGA.9 XF511, photographed in 1974. This is the same type aircraft as that flown by Flight Lieutenant Pollack, 5 April 1968. (Mike Freer/Wikipedia)

The FGA.9 was 33 feet, 8 inches (10.262 meters) long with a wingspan of 45 feet, 10½ inches (13.983 meters) and height of 13 feet, 2 inches (4.013 meters). The wing area was 340 square feet (31.6 square meters). The wings were swept back 40° at ¼-chord, and had an angle of incidence of 1½°. There is noticeable anhedral. The FGA.9 had and empty weight of 13,010 pounds (5,901 kilograms) and maximum takeoff weight of 18,000 pounds (8,165 kilograms).

The FGA.9 was powered by a single Rolls-Royce RA.28 Avon 207 engine. This was a single-shaft axial-flow turbojet with a 15-stage compressor and 2-stage turbine. The RA.28 was 10 feet, 3.0 inches (3.124 meters) long, 3 feet, 5.5 inches (1.054 meters) in diameter, and weighed 2,869 pounds (1,301 kilograms). It was rated at 10,050 pounds of thrust (44.7 Kilonewtons).

Hawker Hunter FGA.9 XF442 at RAF Lossiemouth, 1979. This is the airplane flown through Tower Bridge, 5 April 1968. (Peter Nicholson via Airport-Data.com)

The Hunter FGA.9 had a maximum speed of 702 miles per hour at 15,000 feet (4,572 meters)—0.97 Mach—and maximum range of 1,850 miles (2,977 kilometers) with external fuel tanks.

The basic armament of the Hunter were four 30 mm ADEN autocannon installed in a removable gun pack, along with 150 rounds of ammunition per gun. The ADEN was a gas-operated revolver cannon, capable of firing 1,200–1,400 rounds per minute. The FGA.9 could also carry a 1,000 pounds (454 kilograms) bomb under each wing, twenty-four 3-inch rockets, or two rocket pods with thirty-seven 2-inch rockets, each, for ground attack.

Hawker produced 144 of the Hunter FGA.9 ground attack variant, with 12 modified from F.6 interceptors. Most of Hawker’s foreign sales were based on the FGA.9.

Hawker Hunter FGA.9 XF442 was transferred to the Fuerza Aérea de Chile, 24 April 1982, and assigned identification number J-742. It crashed near Antofagasta, in northern Chile, 20 May 1982.

Alan Pollock was recently interviewed for the Daily Mail:


© 2018, Bryan R. Swopes

26 August 1963


“Housewife Diana Barnato Walker, 45, waves as she climbs into her RAF Lightning jet fighter at Middleton St. George, England, Monday, the day she became the world’s fasted woman aviator. Mrs. Walker, who has a 14-year-old son, flew the plane at 1,250 m.p.h., breaking the official record set by France’s Jacqueline Auriol. Mrs. Walker is a trainer-pilot in the Women’s Junior Air Corps. UPI Radiotelephoto” —The Palm Beach Post, 29 August 1963, Page 51

26 August 1963: Mrs. Diana Barnato Walker, a former pilot with the Air Transport Auxiliary during World War II, flew an English Electric Lightning T Mk.4, XM996, with Squadron Leader Kenneth Goodwin, from RAF Middleton St. George. Her request to make the flight had been approved by Secretary of State for Air Sir Hugh C. P. J. Fraser, MBE. This was the 27th anniversary of her very first flight, which was made in a de Havilland DH.82 Tiger Moth.

Barnato Walker took the controls of the Lightning soon after takeoff, and climbed to 56,000 feet, accelerating toward Mach 1.6. The duration of the flight was approximately 40 minutes.

The Daily Herald quoted her as saying, “Of all the aircraft I have ever flown this is a lady’s dream plane. It flies so quietly and smoothly and responds perfectly.”

The Chelsea News reported:


Flies 1,250 mph at 56,000 feet


Mrs. Diana Barnato Walker, of No. 3 Chelsea Embankment, has become the first woman pilot to be a member of the 350-strong Ten Ton Club, all of whose members are pilots who have flown over 1,000 m.p.h. — there are only two other women members in the world. She is the mother of a 14-year-old boy, Barney.

     Mrs. Barnato-Walker made her flight on Monday in a two-seater Lightning T.4 from the R.A.F. station at Middleton St. George, Yorkshire. Her co-pilot was Squadron-Leader Kenneth Goodwin.

     “It was absolutely wonderful,” said Mrs. Barnato-Walker on Wednesday. “It was terribly quiet in the Lightning when we were supersonic because we were going so fast that we left the noise of the plane behind.”

     Immediately after taking off, she took over the control and remained in charge for most of the 40-minute flight.

     The maximum speed was 1,250 mph (mach 1.6).

     The plane belonged to No. 2 Squadron, 226 Operational Conversion Unit, stationed at Middleton St. George.

Mrs. Barnato-Walker was allowed to do the flight because it was thought she would then be better qualified to inspect cadets in the Women’s Junior Air Corps.


     She was officially made a member of the Ten Ton Club when she landed, and was presented with the exclusive club tie.

     She was guest of honor at a party held for her in the mess.

     A few days before the flight, Mrs. Barnato-Walker had to go through the official R.A.F. decompression test because of the high altitude (56,000 ft.) at which the flight was made. She had to wear RAF safety gear during the flight. If she had not passed the decompression test she would not have been allowed to do he “ten ton.”

     Mrs. Barnato-Walker, who was featured in the NEWS on February 8, is corps pilot in the Women’s Junior Air Corps and spends most of her week-ends and spare time giving flights to young cadets of the various units in the British Isles, helping them become air-minded and perhaps take up a career in flying.


     She is the daughter of the late Wolf Barnato, the racing motorist, and the grand-daughter of Barney Barnato, the South African diamond millionaire.

     During the war she piloted nearly every British military bomber and fighter plane then in existence when she was in the ferry service.

     She became a pilot in 1936, at the earliest possible age.

Chelsea News, No. 5,369, Friday, 30 August 1963, Page 1, Columns 4 and 5

Although many sources state that Mrs. Barnato Walker established a world speed record, breaking one set by Jacqueline Auriol in a Mirage III R on 14 June 1963,¹ the Fédération Aéronautique Internationale online data base does not show any official FAI records credited to her. Other sources state that she was the first British woman to break the “sound barrier.” However,  Flight Officer Jean Oakes WRAF, accomplished this 13 September 1962, when along with Flight Lieutenant John Smith, when she also flew a Lightning T.4 from RAF Middleton St. George to Mach 1.6. (Flight Officer Oakes, a recruiting officer, may not have been a qualified pilot.)

Diana Maitland Barnato was born 15 January 1918, at Camden Town, London, England, during a Zeppelin raid. She was the daughter of Joel Woolf (“Babe”) Barnato and Dorothy Matland Falk Barnato; grand-daughter of Barney Barnato [Barnet Isaacs], the owner of the Barnato Diamond Mining Company, Kimberly Mine; Kimberley Central Diamond Mining Company; co-founder with Cecil Rhodes of the De Beers Consolidated Mines; and owner of the New primrose Gold Mining Company and the Johannesburg Estate Company.

She attended Queen’s College, Harley Street, London, until 1936.

As a debutante, Miss Barnato was presented to King Edward VIII at Buckingham Palace.

At the age of 18, she earned pilot license at  Brooklands Flying Club, while flying a de Havilland DH.82 Tiger Moth.

Nurse Barnato

With the onset of World War II, Miss Barnato joined the Red Cross as a nurse. She served in France until the evacuation of British forces at Dunkirk.

In order to join the Air Transport Auxiliary, an organization of civilian pilots which ferried military aircraft for the Royal Air Force, on 9 March 1941 Miss Barnato took a qualification flight with the ATA’s chief instructor, A.R.O. Macmillan. Having qualified, she was sent to the ATA elementary flying school at White Waltham Airfield, Berkshire, England, in November 1941. On completion of training, she was assigned to the Air Transport Auxiliary Ferry Pool No. 15, RAF Hamble, Hampshire, 9 May 1942.

First Officer Diana Barnato, Air Transport Auxiliary.

In May 1943, she First Officer Barnato was reprimanded for “appearing at Windsor Races wearing trousers and side cap.” She was again reprimanded the following month for “diversion of operational aircraft,” and demoted to 3rd Officer.

During the War, Barnato flew more than 80 aircraft types, and delivered more than 260 Supermarine Spitfires.

Diana Barnato, Air Transport Auxiliary, with a Supermarine Spifire durin World War II. (Ministry of Supply)
Diana Barnato, ATA

On 6 May 1944, Diana Barnato married Wing Commander Derek Ronald Walker, RAF, at St. Jude’s Church, Englefield Green, Runnymead, Surrey, England. A few months later, she and her new husband took a pair of Supermarine Spitfire IXs and flew to Brussels, Belgium. Because this was an unauthorized flight, both newlyweds were fined three months pay.

Wing Commander Walker was killed 14 November 1945, while flying a North American Mustang IV, KM232, in bad weather. His remains were buried at Englefield Green Cemetery.

Mrs. Barnato Walker never remarried. She did have a 30-year relationship with  Air Commodore Whitney Willard Straight, CBE, MC, DFC, FRSA, FRGS. (Some sources state that they had a son, Barney Barnato Walker, while others indicate that he had been adopted.)

Mrs. Barnato Walker received the Jean Lennox Bird Trophy from Lord Brabazon, 1963. (RAeC)

In 1963, she was presented the Jean Lennox Bird Trophy of the British Women Pilots Association, which is awarded to a British woman who has made a noteworthy contribution to aviation, by Lord Brabazon. The trophy is a pale celadon vase and cover, approximately 20 centimeters high.

On 12 June 1965  Mrs. Barnato Walker was made an Ordinary Member of the Civil Division of the Most Excellent Order of the British Empire (MBE) “for services to the Air Transport Auxiliary and the Girls Venture Corps.”

She was the Master of Foxhounds of the Old Surrey and Burstow Hounds, and Commodore ATA Association. She worked at sheep farming in Surrey.

She was the author of Spreading My Wings, an autobiography published in 1994.

Miss Diana Barnato with Ernest Ide, circa 1938. (Steven Iceton)

At the age of 88 years, Mrs. barnato Walker flew in a two-plane Supermarine Spitfire. She said “It would be impolite not to.”

Diana Barnato Walker, MBE, died of pneumonia, 28 April 2008, in a hospital in Surrey, at the age of 90 years. Her funeral was held at Horne Church, Surrey, on Thursday, 15 May 2008.

Diana Barnato-Walker flew this English Electric Lightning T.4, XM996, to Mach 1.6 at 30,000 feet, 26 August 1963. (Russ Smith)

The English Electric Lightning T Mk.4 is a two-place, twin-engined, mid-wing monoplane interceptor trainer. A crew of two sit side-by-side in the cockpit. It is 55 feet, 3 inches (16.840 meters) long, with a wing span of 34 feet, 10 inches (10.617 meters) and height of 19 feet, 7 inches (5.969 meters). The wings have an angle of incidence of 2°‚ and 3° anhedral. The leading edges are swept aft 60° and the trailing edges, 51°56′. At the root, the wing’s chord is 18 feet, 6 inches(5.638 meters) tapering to a theoretical 1 foot, 3.72 inches (0.399 meters) at the rounded tip. The variable incidence tail plane has a span of 14 feet, 6 inches (4.420 meters) with a 60° sweep. The Lightning T Mk.4 carries 966 Imperial gallons (4,392 liters or 1,160 U.S. gallons) of fuel in seven tanks throughout the fuselage and wings.

The Lightning is powered by two vertically-mounted axial-flow Rolls-Royce Avon Mk. 22001 afterburning turbojet engines. These are each rated 11,200 pounds (49.820 kilonewtons) static thrust at Sea Level, and 14,400 pounds (64.054 kilonewtons) with afterburner. One engine, No. 2, is mounted above and to the rear of engine No.1. The engines are limited to 100% +/- 0.5% r.p.m., for 15 minutes, and 97.5%, for 30 minutes. Maximum Continuous Power is restricted to 95% r.p.m.

The ventral fuel tank is clearly visible as the English Electric Lightning T Mk.4 rolls away from the camera.

The Lightning T Mk.4 has an empty weight of 24,815 pounds (11,256 kilograms), and all-up weight of 34,914 pounds (15,837 kilograms), with a ventral fuel tank installed. Maximum Takeoff Weight (MTOW) is 35,000 pounds (15,876 kilograms).

The Lightning’s maximum speed limitation is Mach 1.7. With no missiles carried, it is restricted to 650 knots (748 miles per hour/1,204 kilometers per hour) Indicated Air Speed; with two missiles, 600 knots (690 miles per hour/1,111 kilometers per hour) IAS below 25,000 feet; and 650 knots IAS above 25,000 feet (7,620 meters). The trainer’s approach speed is 175–180 knots (201– 207miles per hour/324 –333 kilometers per hour).

The T Mk.4’s maximum load factor is 6 g up to 0.9 Mach, or 5.5 g, above (empty or no ventral tank). The maximum negative acceleration is 3g.

The Lightning T Mk.4 is limited to a maximum altitude of 60,000 feet (18,288 meters).

The interceptor trainer can be armed with two ADEN 30mm guns or two de Havilland Firestreak heat-seeking missiles, and in addition to its primary training function, is fully operational as a fighter.

¹ FAI Record File Number 12392, 2,038.70 kilometers per hour (1,266.79 miles per hour)

© 2023, Bryan R. Swopes