The Aero A.11, a biplane light bomber and reconnaissance aircraft, was manufactured in Czechoslovakia during the period between the First and Second World Wars.
This aircraft served as a foundation for numerous other military aircraft developed in Czechoslovakia during the interwar era.
Approximately 250 units were constructed, and a few of them were still operational when World War II commenced.
Antonin Husnik was the mastermind behind the design of this aircraft, which was an advancement of the Aero A.12, despite the misleading numbering system.
The Finnish Air Force, being the sole foreign operator of this model, had a variant called A.11H-s that was equipped with a Hispano-Suiza 8Fb engine.
The Finns possessed a fleet of eight of these aircraft and effectively utilised them from 1927 to 1939.
Variants
A.11
Two-seat light bomber, reconnaissance biplane.
A.11HS
Export version for Finland.
A.11N
Night bomber version.
Ab.11
Light bomber version.
Specifications
Ab.11
Crew
2
Length
8.2 m (26 ft 11 in)
Wingspan
12.8 m (42 ft 0 in)
Height
3.1 m (10 ft 2 in)
Wing area
36.5 m2 (393 sq ft)
Empty weight
1,080 kg (2,381 lb)
Gross weight
1,588 kg (3,501 lb)
Powerplant
1 × Breitfield-Danek Perun II,
6-cylinder water cooled inline piston engine,
180 kW (240 hp)
Or
(A.11)
Walter W.IV
176 kW (236 hp)
Propellers
2-bladed fixed-pitch propeller
Performance
Maximum speed
216 km/h (134 mph, 117 kn) Ab.11
240 km/h (150 mph; 130 kn) A.11
Cruise speed
190 km/h (120 mph, 100 kn)
Range
750 km (470 mi, 400 nmi)
Service ceiling
7,000 m (23,000 ft) Ab.11
7,600 m (24,934 ft) A.11
Rate of climb
3.82 m/s (752 ft/min)
Time to altitude
5,000 m (16,404 ft) in 19 minutes 30 seconds
Wing loading
43.7 kg/m2 (9.0 lb/sq ft) Ab.11
42 kg/m2 (8.6 lb/sq ft) A.11
Power/mass
0.120 kW/kg (0.073 hp/lb)
Armament
Guns
1× forward firing .303 in (7.7 mm) Vickers machine gun
2× .303 in (7.7 mm) Lewis machine gun in flexible mount for observer
Bombs
200 kg (441 lb)
Sources
Czechoslovakian Air Force, 1918-1970, Aircam Aviation Special 05-Richard Ward, Zdenek Titz & Gordon C. Davies.
Ceskoslovenské Letectvo, 1918-1924-Jiří Rajlich & Jiří Sehnal.