Avro 549 Aldershot, 561 and 563 Andover

Four seat long range heavy bomber to meet Specification DofR Type 4B (later Air Ministry Specification 2/20). It was a three-bay biplane, with a steel-framed fuselage structure built in three sections, with plywood and fabric covering. The fabbric covered wooden wings were unstaggered and unswept, the main panels of which could fold back along the fuselage sides. Ailerons were fitted to both upper and lower mainplanes. Initially the fin was very long and shallow, with the tailplane mounted on top of the fin. The oval shaped rudder featured horn balances top and bottom. The fin was eventually reduced in size to just that to support the tailplane, with the rudders upper horn balance greatly increased in area. The pilot and navigator were seated side by side in a cockpit behind the upper wing trailing edge, with additional accommodation for the navigator who was also the bomb-aimer, in a cabin inside the fuselage, which was provided with four circular windows on each side. A gunner sat in a separate cockpit behind the pilot, and was armed with a single .303-in Lewis gun on a Scarff ring. Another Lewis gun could be fitted to a ventral mounting in the cabin, while there was provision for a fixed, forward-firing Vickers machine gun operated by the pilot, although this was rarely fitted. A bomb bay forward of the cabin could hold eight 250 lb bombs, with larger bombs being carried externally under the fuselage. One 650 h.p. Rolls-Royce Condor III powerplant.

As Mk.I with lengthened fuselage and 1000 h.p. Napier Cub powerplant.

Production version featuring the lengthened fuselage of the Mk.II, with swept wings to compensate for the aft movement of the c.g., along with strengthened undercarriage and additional fuel tanks above the upper wings. e Rolls-Royce Condor III powerplant.
Possibly to Specification 10/23, although Avro may have had a new design to this spec [4].

One Mk.III experimentally fitted with a set of unswept, fabric covered, steel wings.

As Mk.III with 850 h.p. Beardmore Typhoon I powerplant.

Type 549 Aldershot Mk.III Specification
Span	Length	Height	Wing Area	Empty Wt	Max AUW	Cruise Speed	Maximum Speed	Range	Service Ceiling
68 ft	45 ft	15 ft 3 in	1064 sq ft	6310 lb	10950 lb	92 mph/ 80 kn	110 mph/ 96 kn	625 mi	14500 ft
20.73 m	13.72 m	4.65 m	98.85 m2	2862 kg	4967 kg	148 km/h	177 km/h	1006 km	4420 m

Military transport and air ambulance based on the Aldershot with new passenger fuselage to meet Specification 29/23. The fuselage was a steel tube frame covered with canvas and plywood. While the fuselage was a completely new design, the wings, undercarriage and the tail unit were taken from the Type 549 Aldershot Mk.III. The pilot and navigator sat in an open cockpit directly under the leading edge of the upper wing; a passageway led from the cockpit to the passenger cabin. The aircraft held twelve passengers (six on each side of the centre aisle) or six stretchers. One 650 h.p. Rolls-Royce Condor III powerplant.

12 passenger civil variant of Type 561, with an additional washroom and a baggage compartment.