Tag Archives: Gerry Sayer

12 September 1934

Gloster SS.37 G7, prototype Gloster Gladiator
The Gloster G.37, prototype of the Gloster Gladiator Mk.I (Gloster Aircraft Co., Ltd.)

12 September 1934: Hawker Aircraft Company test pilot Flying Officer Phillip Edward Gerald Sayer made the first flight of the Gloster G.37, a prototype fighter for the Royal Air Force, designed to reach a speed of 250 miles per hour (402 kilometers per hour) while armed with four machine guns. The flight took place at Gloster’s private airfield at Brockworth, Gloucestershire.

The Gladiator was a single-place, single-engine, single-bay biplane, with fixed landing gear. The airplane was primarily of metal construction, though the aft fuselage, wings and control surfaces were fabric covered.

The production Gladiator Mk.I was 27 feet, 5 inches (8.357 meters) long with a wingspan of 32 feet, 3 inches (9.830 meters) and overall height of 11 feet, 9 inches (3.581 meters). It had an empty weight of 3,217 pounds (1,459 kilograms) and gross weight of 4,594 pounds (2,084 kilograms).

Gloster SS.37 prototype, right profile
Gloster G.37 prototype, right profile

The G.37 was equipped with a left-hand tractor, air-cooled, supercharged, 1,519.083 cubic-inch-displacement (24.893 liters) Bristol Mercury IV-S2 nine cylinder radial engine. With a compression ratio of 5.3:1, the IV-S2 was rated at  505 horsepower at 2,250 r.p.m., and 540 h.p. at 2,600 r.p.m., both at 13,000 feet (3,962 meters). It developed a maximum 560 horsepower at 2,600 r.p.m. at 16,000 feet (4,877 meters). The engine had a take-off power rating of 530 horsepower at 2,250 r.p.m., at Sea Level (3-minute limit). The IV-S2 drove a two-bladed fixed-pitch propeller through a 0.655:1 gear reduction. This engine weighed 920 pounds (417 kilograms).

The G.37 was repowered with a Bristol Mercury VI-S engine, which had a 6:0:1 compression ratio and a 0.5:1 gear reduction ratio. This engine produced a maximum of 636 horsepower at 2,750 r.p.m. at 15,500 feet.

The prototype was armed with two synchronized, air-cooled Vickers .303-caliber machine guns, firing forward through the propeller arc, and two .303-caliber Lewis guns mounted under the bottom wing.

With the upgraded engine and armament, the G.37 reached 242 miles per hour (389 kilometers per hour).

The Gloster Gladiator Mk.I with an enclosed cockpit and a Bristol Mercury IX engine had a maximum speed of 257 miles per hour (414 kilometers) per hour) at 14,600 feet (4,450 meters).

This production Gloster Gladiator Mk.I, K6131, shows the cockpit enclosure. (This airplane, the second production Gladiator Mk.I, was damaged beyond repair when it ran out of fuel near RAF Church Fenton, 26 March 1938.) (Royal Air Force)
Gloster Gladiator Mk.I L8032. (SDASM)

The Gladiator Mk.I entered service with the Royal Air Force in February 1937. It was the last biplane fighter to do so, and was the first fighter with an enclosed cockpit. Beginning with No. 72 Squadron, eight fighter squadrons were equipped with the type, though by the beginning of World War II, these were being phased out by more modern airplanes like the Hawker Hurricane and Supermarine Spitfire.

A total of 737 Gloster Gladiators, Mk.I and Mk.II, were built. In addition to the Royal Air Force, there were operated by several other countries in Europe, the Mediterranean and the Middle East.

Prototype Gloster Gladiator in flight, now marked K5200.
Prototype Gloster Gladiator G.37 in flight, now marked K5200. A .303-caliber Lewis machine gun is visible under the right wing. (Royal Air Force)
Phillip E.G. Sayer, O.B.E. (Flight)

Phillip Edward Gerald Sayer was born at Colchester, England, 2 February 1905. He was the second of three children of Edward James Sayer, a retired British Army officer and Ethel Jane Hellyar Sayer.

Sayer was granted a short service commission in the Royal Air Force as a Pilot Officer on probation, 30 June 1924. His rank was confirmed 23 May 1925. He was promoted to Flying Officer 30 March 1926. Flying Officer Sayer was transferred to the R.A.F. Reserve, 2 March 1929.

In 1930, Gerry Sayer joined Hawker Aircraft Company as a test pilot. When Hawker took over Gloster Aircraft Co., Ltd. in November 1934, he was appointed Chief Test Pilot of Gloster.

Flight Lieutenant Sayer completed his service and relinquished his commission, 2 March 1937. He was permitted to retain his rank.

On 15 May 1941, Sayer made the first flight of the Gloster-Whittle E.28/39, a prototype jet fighter.

Chief Test Pilot Phillip Edward Gerald Sayer, Esq., was appointed an Officer of the Most Excellent Order of the British Empire (OBE) in the New Years Honours list, 30 December 1941.

Gerry Sayer was flying a Hawker Typhoon from RAF Acklington, 22 October 1942, to the Druridge Bay gunnery range. He never returned.

© 2018, Bryan R. Swopes

15 May 1941

Gloster-Whittle E.28/39 W4041/G in its original configuration. The horizontal paint stripe was used as an indication of heating by the turbojet engine. (BAE Systems)
Phillip E.G. Sayer (Flight)
Phillip E.G. Sayer (Flight)

15 May 1941: Having been delayed by weather until 7:40 p.m., Gloster Aircraft Co., Ltd., Chief Test Pilot Phillip Edward Gerald Sayer taxied into position on the long, hard-surfaced runway at RAF Cranwell, stood on the brakes and advanced the throttle. When the engine reached 16,000 r.p.m., Sayer released the brakes and the little airplane began to roll forward.

Acceleration was slow. Relying on the feel of the flight controls rather than a pre-calculated airspeed, Sayer lifted off after 600–700 yards (550–640 meters), at about 80 miles per hour (129 kilometers per hour). At 1,000 feet (305 meters), he retracted the landing gear and continued to climb at reduced r.p.m. He reached a maximum 240 miles per hour (386 kilometers per hour) Indicated Air Speed at 4,000 feet (1,219 meters).

Sayer landed after a 17-minute first flight.

Gerry Sayer's knee board notations from the Gloster E.28/39 first flight, 15 May 1941. (Hartley Moyes, courtesy of Neil Corbett, Test and Research Pilots, Flight Test Engineers)
Gerry Sayer’s knee board notations from the Gloster E.28/39 first flight, 15 May 1941. (Hartley Moyes, courtesy of Neil Corbett, Test and Research Pilots, Flight Test Engineers)

The airplane was the Gloster-Whittle E.28/39, registration W4041/G, the first of two prototype fighters powered by a turbojet engine. (The “/G” in the registration indicates that, for security reasons, the airplane is at all times to be under guard when on the ground.) It was a single-seat, single-engine, low-wing monoplane of all-metal construction. The E.28/39 had retractable tricycle landing gear, one of the first fighter-type aircraft with that configuration.

The Gloster E.28/39 was 25 feet, 3 inches (6.696 meters) long with a wingspan of 29 feet, 0 inches (8.839 meters) and overall height of 9 feet, 3 inches (2.819 meters). It had a fuel tank of just 81 gallons (368 liters) capacity. The prototype’s takeoff weight was 3,341 pounds (1,515 kilograms).

Power Jets, Ltd. Whittle Supercharger Type 1 turbojet engine, as seen from the front. (Science Museum Group)
Power Jets, Ltd., Whittle Supercharger Type W.1 turbojet engine, as seen from the front. Air enters the compressor through barely visible intakes in the sides of the cast aluminum alloy compressor case. (Science Museum Group)
Whittle W.1 combustion chambers and exhaust as seen from the rear. The turbine section was water-cooled. (Getty Images/Science & Society Picture Library)
Whittle W.1 combustion chambers and exhaust as seen from the rear. The turbine section was water-cooled. (Getty Images/Science & Society Picture Library)

W4041/G was powered by a single Power Jets, Ltd., Whittle Supercharger Type W.1. The turbojet used a single-stage, centrifugal-flow compressor, ten reverse-flow combustion chambers, and a single-stage axial-flow turbine. The turbine had 72 blades. The W.1 produced 860 pounds of thrust (3,825.47 Newtons) at 16,500 r.p.m., burning paraffin (kerosene).

Gloster-Whittle E.28/39 W4041/G, front. (Gloster)
Gloster-Whittle E.28/39 W4041/G, front. (Gloster)

The E.28/39 had a single large air intake at the nose. This split into two ducts which passed around each side of the the cockpit, following the inner contours of the fuselage, and then entered a plenum chamber. Intake air was compressed approximately 4:1 and passed to the combustion chambers. Fuel was mixed with this heated, compressed air, then ignited. Flame temperatures approached 600 °C. (1,112 °F.) This very hot, expanding gas flowed through spiral ducts to the turbine blades, causing the turbine disc to spin to a maximum 17,750 r.p.m., above 4,000 feet (1,219 meters).

Diagram of fuselage arrangement of E.28/39. (Air Cdre Sir Frank Whittle)

The turbine drove the compressor at the front of the engine through a central drive shaft. The exhaust gas left the engine and passed through a straight pipe to the rear of the fuselage. The high velocity gas exiting the tail of the aircraft—thrust—resulted in the aircraft being propelled forward at a proportional velocity.

Gloster-Whittle E.28/39 W4041/G, rear (Gloster)
Gloster-Whittle E.28/39 W4041/G, rear (Gloster)

Because of limitations in materials technology, the Whittle W.1 had a limited service life of just ten hours. To keep the most time available for flight tests, early static and taxi tests of the Gloster prototype were made using an engine built from non-airworthy parts and spare components. This engine was designated W.1X.

Over the next thirteen days, Gerry Sayer made fourteen flights, totaling ten hours. The E.28/39 reached a maximum of 25,000 feet (7,620 meters) and 300 miles per hour (483 kilometers per hour). W4041/G was restricted to 2g maneuvers because of stress placed on the cast aluminum compressor case.

Gloster test pilots conducted three series of flight tests with W.4041/G. With Gloster test pilot John Grierson in the cockpit, on 24 June 1943, W4041/G climbed to 41,600 feet (12,680 meters) in 27 minutes, and reached an absolute maximum altitude of 42,170 feet (12,853 meters). This flight completed Gloster’s flight test program and the airplane was turned over to RAE Farnborough.

A second Gloster E.28/39 was built, W4046/G. Using an improved Whittle W.2/700 turbojet engine, the second prototype reached a maximum speed of 505 miles per hour (813 kilometers per hour) in level flight at 30,000 feet (9,144 meters)—0.74 Mach.

On 30 July 1943, W4046 was lost when its ailerons jammed at high altitude. The pilot bailed out and parachuted safely, but the prototype jet airplane was destroyed.

Wreckage of W4046/G
Wreckage of the second prototype Gloster E.28/39, W4046/G

On 27 April 1946, Gloster-Whittle E.28/39 W4041/G was placed in the National Aeronautical Collection, Science Museum, South Kensington, 27 April 1946.

Chief Test Pilot Phillip Edward Gerald Sayer, Esq., was appointed an Officer of the Most Excellent Order of the British Empire (OBE) on the New Years Honours list, 30 December 1941. He was killed in flying accident 22 October 1942, probably the result of a mid-air collision.

RECOMMENDED: “No Airscrew Necessary. . .” by Robert J. Blackburn, Flight and Aircraft Engineer, No. 2131, Vol. LVI., Thursday, 27 October 1949, at pages 553–558

Gloster-Whittle E.28/39, W4041/G, piloted by Squadron Leader J. Moloney, takes off from RAE Farnborough for a test flight. (Flight Lieutenant Stanley Devon, Royal Air Force Official Photographer. © Imperial War Museum CH 14832A)
Gloster-Whittle E.28/39, W4041/G, now in standard camouflage and RAF markings, piloted by Squadron Leader J. Moloney, takes off from RAE Farnborough for a test flight. Note the small outboard vertical fins on the horizontal stabilizer. (Flight Lieutenant Stanley Devon, Royal Air Force Official Photographer. © Imperial War Museum CH 14832A)

© 2017, Bryan R. Swopes