Avro Baby
The Avro 534 Baby—initially called the "Popular"—was a British lightweight, single-seat sporting biplane developed shortly after the conclusion of the First World War.
Development
The Avro Baby featured a conventional single-bay biplane design, constructed with a wooden frame braced by wires and covered in fabric. Its wings were equal in span and unstaggered, each equipped with two pairs of ailerons. Early models lacked a vertical fin and had an almost circular rudder. Subsequent versions introduced modifications to this arrangement. The landing gear consisted of a fixed main undercarriage with a single axle and a tailskid.[1]
Initial production Babies were powered by water-cooled inline Green C.4 engines, a design dating from before 1914 that had been previously installed in the Avro Type D. These engines were extensively reworked after the war by the Green Engine Co.[2] Delivering 35 hp (26 kW), this engine was used in most later Babies as well, manufactured anew from original Green blueprints by Peter Brotherhood Limited of Peterborough. Some variants, however, employed either a 60 hp (45 kW) ADC Cirrus 1 or an 80 hp (60 kW) Le Rhône. The newly built Green engines were approximately 6 lb (3 kg) lighter.
The prototype made its maiden flight on 30 April 1919 at Avro's Hamble airfield but crashed on the adjacent shoreline within two minutes due to pilot error. The second prototype successfully flew on 31 May 1919.[2]
A floatplane variant named the Type 534A Water Baby featured an enlarged fin and modified rudder. Counting the brief-lived prototype, the fourth Baby was designated Type 534B and distinguished by its plywood-covered fuselage and a shortened lower wing span. The Type 534C had clipped wings optimized for racing in the 1921 Aerial Derby. The Type 534D was adapted for operations in hot climates and was utilized by a businessman in India. All these Type 534 models were single-seaters powered by Green engines.[3]
The Type 543 Baby was designed as a two-seat aircraft with a fuselage extended by 2 ft 6 in (76 cm). Initially fitted with a Green engine, it was later re-engined in 1926 with an air-cooled upright inline ADC Cirrus 1 producing 80 hp (60 kW).[4]
The final iteration was the type 554 Antarctic Baby, constructed as an aerial photographic platform for the 1921–1922 Shackleton–Rowett Expedition to Antarctica. It incorporated an 80 hp (60 kW) Le Rhône engine, raised tailplanes, rounded wingtips, and replaced traditional rigging wires with tubular steel interplane struts to facilitate handling while wearing gloves. Like the Water Baby, this model was configured as a floatplane.[5]
Among the most unusual adaptations was one altered by H.G. Leigh in 1920.[6] This modification involved removing the original wings and fitting a short shoulder-mounted conventional wing equipped with full-span projecting ailerons. Above this wing was mounted a strongly forward-staggered stack of six very narrow-chord wings of similar span to the lower wing; each possessed high aspect ratios to reduce induced drag. This complex arrangement increased weight by roughly 60 lb (30 kg). Known as the "Venetian blind" wing configuration, this concept had been proposed and investigated earlier by Horatio Phillips during the late nineteenth century.[7]
Operational history
During the early 1920s, numerous aviators flew the Babies, but they are most famously associated with the achievements of G-EACQ piloted by Bert Hinkler. On 31 May 1920, Hinkler completed a non-stop journey from Croydon to Turin in 9 hours and 30 minutes, covering a distance of 655 mi (1,050 km). This accomplishment was hailed at the time as "the most meritorious flight on record." Subsequently, on 24 July, he secured second place in the handicap section of the Aerial Derby held at Hendon. Later, on 11 April 1921, Hinkler established a new Australian distance record by flying the Baby non-stop from Sydney to his hometown of Bundaberg, a span of 800 mi (1,288 km), completing the trip in 8 hours and 40 minutes. The Baby flown by Hinkler is now exhibited at the Hinkler Hall of Aviation located in Bundaberg.
In June 1922, a different Baby accomplished the inaugural flight between London and Moscow when the Russian pilot Gwaiter retrieved his aircraft from Hamble and flew it back to Russia.
Ernest Shackleton intended to bring an Avro Baby 'Antarctic' on his final expedition aboard the Quest. However, due to engine difficulties delaying the ship and its subsequent decision to bypass Cape Town—the destination where the Avro had been transported—the aircraft was ultimately excluded because it occupied excessive space on board.
Specifications (534 Baby, post-war Green engine)
References
Bibliography
- Jackson, A.J. Avro Aircraft since 1908. London: Putnam Aeronautical Books, 2nd edition, 1990. ISBN 0-85177-834-8.
- Taylor, John W. R. A Picture History of Flight. London: Hulton Press, 1955.
- Taylor, Michael J. H. Jane's Encyclopedia of Aviation. London: Studio Editions, 1989. ISBN 0-517-69186-8.
Further reading
- "The Avro "Baby" Sporting Biplane". Flight. XI (26): 831–836. 26 June 1919. No. 548. Retrieved 12 January 2011. A period technical overview featuring illustrations and photographs.