|Sikorsky S-22 Il'ya Muromets|
|Designer||Igor I. Sikorsky|
|First flight||11 Dec 1913 |
|Variants||S-23, S-24, S-25, S-26, S-27|
|Wingspan||30.9 m (101 ft 6 in) |
510 kg (1,120 lb) of bombs 
|Max Speed||97 km/h (60 mph) |
|Ceiling||2,000 m (6,500 ft) |
After the Sikorsky S-21 Grand had proved the basic concept, Sikorsky moved to the design known as the Sikorsky S-22 Il'ya Muromets. The prototype S-22A first few in December 1913, and after several test flights it was converted to a floatplane for testing by the Imperial Navy. The second prototype, the Type B, featured more powerful engines an a somewhat smaller size and flew from St. Petersburg to Kiev and back. Seven "Type B" planes were built with various combinations of engines.
Since they were completed before the war, the S-22's were intended as transports and it was only in the S-23 that it would be adapted as a bomber. Several various refinements of the basic type resulted in the S-23 to S-27 line of Il'ya Muromets bombers. 
For more information, see Wikipedia:Sikorsky Ilya Muromets.
- Durkota, p.311.
- Lamberton, pp.228-229.