Mew Gull - Technical Specifications

Original configuration


Data of G-AEXF with Gipsy Six ‘R’ engine prepared for King’s Cup Race 1938

Length 21 ft. 11 in. Height 6 ft 6 in. Span 24 ft 9 in. Wing area 88 sq. ft. All-up wt 2125 lb
Maximum speed at sea-level over 270 mph Initial climb over 1800 ft/min.
Cruising speed 240 mph at 7000 ft

Some of the modifications made during 1937/1938 by Essex Aero Ltd

1 Gipsy Six ‘R’ engine fitted. Nominal hp 225, compression ratio 6.5:1.
2 Extension to crankshaft. Machined from S.81 steel treated to give 55 tons UTS.
3 Specially spun larger and longer spinner fitted, and cowls adapted.
4 Special air-intake of Essex Aero design, induction manifold partly re-routed.
5 Machine fastest with Ratier airscrew which had to be changed for 2-pitch De Havilland type
   to comply with King’s Cup race rules.
6 Pitot-head and control mass-balance weights streamlined.
7 Smaller re-designed wheel-spats fitted.
8 Essex Aero designed spring-steel scale fairings to wheels and spats.
9 Smaller wheels and tyres fitted.
10 All filler caps made with flush lock fittings. 100-octane distilled fuel.
11 One-piece Perspex screen specially moulded.
52 Cabin roof lowered 4 in. to fit pilot’s head.
13 Fuselage top-decking lowered to fit pilot.
54 Tail-skid re-designed, and streamlined.
15 Bottom fuselage decking re-shaped.
16 Chassis oleo-legs redesigned and strapped up with high-tensile cable.
17 Blind-flying venturi designed to swivel in and out of cockpit.
18 Seat removed and replaced with sorbo pad to allow further lowering of cabin roof and
      fuselage top-decking.
59 C of G moved forward with packing at pilot’s back.

Competitions in 1938

June 24    Hatfield—Speke Fastest time 250.25 mph
               Speke—Ronaldsway I.O.M. Race Position 2nd Fastest time 247 mph
June 25    Manx Air Derby Fastest time 239 mph
July 2       King’s Cup race Position 1st Fastest time 236.25 mph
July 3       Folkestone Aero Trophy Position 6th Fastest time 235 mph


Cape records config.

Data of G-AEXF with Gipsy Six Series II engine prepared for Cape records

Modifications made during 1938/1939 by Essex Aero Ltd
Many of the modifications made for the 1938 racing season were retained for the Cape record attempt. In addition the following work was done:

20 Sigmund vacuum pump replaced venturi tube.
21 Gipsy Six Series II engine replaced the 'R'. Nominal horsepower: 205.
22 Oil capacity and cooling increased by special cowling saddle-tank.
23 Special filler funnel which screwed into head of saddle-tank.
24 All petrol tank filler points sealed to prevent over-spill and fumes.
25 Retractable navigation light fitted fuselage top aft of pilot.
26 Airscrew constant speed unit fitted with control welded to cockpit tank.
27 Main fuselage petrol tank enlarged and extended into cockpit.
28 Emergency cockpit petrol tank constructed over pilot’s legs.
29 Instrument panel moved as near pilot’s face as practicable.
30 Chronometer; ASI; revcounter; sensitive altimeter; oil-pressure gauge; Sperry blind-flying panel.
3’ Large Huson P4 compass fitted on special bracket near pilot.
32 Two soup vacuum-flasks fitted with suction tubes.
33 One bag fitted for apples, sweets and milk tablets.
34 Urinating funnel fitted with atmosphere vent.
35 Cockpit air-vent fitted providing warm air to all tanks in ice conditions.
36 Recess built into fuselage to take specially shaped parachute.
37 6.35-mm calibre automatic sewn into parachute harness.
38 Wireless transmitter carried for ground use only in Sahara emergency.
39 Medicine bag fitted containing quinine, benzedrine and aspirin.
40 Locker for logbook, passport, maps and messages.
41 Sun curtains fitted.
42 Flashlamp in lieu of cockpit lighting.
43 British Ensign.
44 Alteration to airscrew blades.


Maximum speed at sea-level: 247 mph Range approximately 2000 statute miles
Cruising speed at 7000 ft: 235 mph
All-up weight increased from 2125 lb to 2350 lb extending C of G beyond aft limits for which a special category certificate was obtained.

Competitions in 1939

Feb 5/9     Not only were all Cape Town-and-return records broken but also those for every stage en route.
                The England—Cape Town—England flight is still in 1999 an all-time record for any aircraft.
                The solo records remain to this day.

May 27    Hatfield—I.O.M. Race Position 2nd Speed 247.5 mph


Source: The Flight of the Mew Gull by Alex Henshaw 1990, 1998 (Air Life Publishing Ltd).