Fig 5.1 - The Parnall Prawn S1576 at Felixstowe possibly in 1930. The engine is in the lowered position. Note the very small propellor necessary as it was so close to the water-line. (IWM photo No. MH2818)

Fig 5.2 - The Parnall Prawn almost certainly photographed on the same occasion as above. The engine is in the fully raised position. Note the height gauge at the left which shows 6 feet, an indication that this was a very small plane. What its flying characteristics were like with a thrust line at such an acute angle is hard to imagine. (IWM photo No. MH2984)

More useful was the Parasol of which two were built. This machine was a flying full-scale aerodynamic test vehicle, it could test the effects seen in wind tunnel tests but without the effects of scale inherent in a tunnel. It was a two seater, the observer occupying the front cockpit which was equipped with a dynamometer for measuring flight loads on the variable incidence wings which featured slots, flaps and separated ailerons. To eliminate the effects of the propeller, the A.S. Lynx engine could be stopped in flight for gliding then restarted with a gas starter. A camera could be mounted on struts above the tailplane and this was used for photographing wool tufts that showed the airflow patterns over the wings. The two aircraft went to Farnborough in August and October 1930 where they were used for nearly 6 years: wings of various serctions were tried including an Avro-built wing with Zap flaps that were similar to Fowler flaps but found to be less efficient.

Fig 5.3 - Parnall Parasol first prototype K1228 possibly at Martlesham Heath. The outer part of the forward wings struts and the short vertical struts were part of the load-measuring system that transmitted data to the observer's cockpit at the wing trailing edge. (IWM photo No. MH3343)

Fig 5.4 Parnall Parasol K1228 in flight, the wool tufts and camera mounting are clearly seen. In this picture the propeller appears to be stopped to provide undisturbed airflow over the wing, The strut projecting forward appears to stop the propeller from windmilling. This photo was from an Avro collection so this may be the Avro designed wing with Zap flaps under test.

The interwar years produced a series of requirements for "general purpose" aircraft; in those miserly times this was a cheap way of providing the Air Force with aircraft that, it was hoped, would be of some general use if hostilities arose. Specification G.4/31 was no exception, conceived as a replacement for the Westland Wapiti and Fairey Gordon, it called for day and night bombing, reconnaissance, torpedo carrying and even dive-bombing although this was later deleted. Designs came from Handley Page, Vickers, Fairey, Armstrong Whitworth and Parnall with what was to be the final expressly military type, the un-named G.4/31.

This was a large angular biplane with gull-type upper wings, wheel spats, a good collection of interplane and fuselage struts and very generous tail surfaces. Power came from a 690hp Bristol Pegasus I M3 in a Townend ring, there was a forward firing gun for the pilot and the observer had a Scarf mounted Lewis gun; flight tests were carried out during 1935 from Yate. It is believed the that aircraft had handling problems, for it was not delivered to Martlesham Heath until early 1936, long after the competition had been decided in favour of the Vickers 253. The machine was used for armament trials until March 1937 when it was damaged in a crash and subsequently scrapped. Vickers chose to submit two designs and the 253 was cancelled in favour of the advanced monoplane Wellesley.

Fig 5.5 - The sole Parnall G4/31, K2772. This picture was probably taken at Yate, note the early polygonal cowling

Fig 5.6 - The Parnall G4/31 in its final form, probably at Martlesham Heath. A Bristol Bulldog is visible in the background by the port wing.

In 1929 Parnall built a cabin monoplane called the Hendy 302 to the design of Basil B. Henderson who followed it with another monoplane, the advanced Heck. 1935 marked a major change for Parnall when the firm acquired the assets of both Hendy Aircraft Ltd. and the armaments firm of Nash and Thompson. A new company called Parnall Aircraft was formed and the Heck passed to Parnall ownership. Renamed the Parnall Heck it set a new record for the run from Cape Town to England of 6 days, 8 hours and 27 minutes in November 1936. A three-seat derivative with a fixed, spatted undercarriage, powered by a Gypsy Six was produced as the Parnall Heck 2C. Six were laid down in expectation of sales but none attracted an order and the first four were to be used as communications aircraft by Parnall in connection with their armaments activities. The fifth and sixth aircraft were used for test flying the Wolseley Aries radial engine and gun sight development work.

Fig 5.7 - Parnall Heck 2C K8853. This particular machine was fitted with a variable pitch propellor and was used for developing the gun-sight installation for the Hurricane and Spitfire.

The final Parnall aircraft was a open two seat trainer derivative of the Heck to specification T.1/37 and called the Parnall 382 or the Heck 3. It featured the Heck's advanced wing and had a speed range of 139mph to 43mph, it made its first flight in 1939. At Marlesham Heath it was pleasant to fly assessed as generally good as a trainer and, with a number of modifications, was acceptable for service but sadly for Parnall no order was forthcoming. It was to be the last Parnall machine to fly, for after that Parnall turned to the vitally needed gun turrets of Archie Frazer-Nash's design which occupied the Yate factory throughout the war.

Fig 5.8 - The final Parnall plane, the un-named 382 shown here in class B conditions as J-1 probably at Yate. It was registered as G-AFKF and was later fitted with a coupe top over the rear cockpit.

With the war over, Parnall was to become a household name through its famous washing machines and later the Jackson range of cookers. One would doubt that George Parnall and his little group could ever have envisaged such a future when for over twenty years they strove to give Bristol another aircraft company whose name would be as famous and as proud as its bigger neighbour.