PWS-23

In the early 1920s the Polish Army was seeking home-made "retribution bombers", that is heavy bombers in modern terminology.[1][2] However, all proposals by Polish aircraft manufacturers were rejected as none were deemed skilled and experienced enough to build large, complicated bombers.[1] Because of that the newly created 2nd Destroyer Squadron of the 1st Air Regiment in 1926 was equipped with 32 Farman Goliath bombers bought in France.[1] However soon it became clear that the French bomber, designed in 1918, was already obsolete. Furthermore, the Goliaths were seriously underpowered and could not fly on one engine only, a serious flaw in a bomber.[3] Because of that the Department of Air of the Ministry of Military Affairs renewed interest in a home-produced heavy bomber.[3]

As a stop-gap solution, the Polish state bought in February 1928 a license for Fokker F.VIIB/3m long-range passenger aircraft to be produced at the Lublin-based Plage i Laśkiewicz works. By the end of that year Jerzy Rudlicki of Plage i Laśkiewicz modified the design to build the plane in bomber configuration as well: windows were sealed, the passenger cabin replaced with bomb racks for up to 1,500 kilograms (3,300 lb) bombs and a single dorsal machine gun nest.[3] The plane, while mechanically sound, was but a stop-gap solution and the Polish Ministry of Military Affairs continued to seek a full-featured replacement for the Goliaths.[3]

Meanwhile the LOT Polish Airlines were seeking a modern passenger plane to replace its ageing fleet of Junkers F.13 and Fokker F.VIIB/3m, and PWS-23T was presented to the Department of Aeronautics to compete with the T-600 design by State Aviation Works in June 1928.[4] PWS' design was more complicated than its competitor, but provided accommodation for up to 20 passengers and 400 kilograms (880 lb) of cargo,[4] twice as much as the competitor. In the end however the T-600 was accepted and a single prototype was built for evaluation under the new PZL.4 designation.[4]

The night bomber shared a similar fate.[4] In 1929 Plage i Laśkiewicz presented the ministry with a much heavier "flying fortress" Lublin R-XVIII design, while PWS sent two projects: PWS-22 and PWS-23.[3] Eventually all designs were rejected and the unsuccessful LWS-6 Żubr was chosen as an interim design before the modern PZL.37 Łoś could be introduced in the 1930s.[5] The PWS-23 remained a project only.

The PWS-23 was a high parasol wing aircraft of mixed construction, with a fixed undercarriage.[4] A geodetic airframe of welded steel or aluminium tubing was to be covered with plywood and canvas.[4] The wooden parasol wings reinforced with two girders were attached to the fuselage with a pyramid-like mounting.[4]

Defensive armament included 5 machine guns, including two in a double nose mount, 2 in a double dorsal mount and 1 in a ventral retractable turret.[4] The bombload was to exceed 2,000 kilograms (4,400 lb).[4] The avionics included a radio, electric installation for night flights and cabin heating for the crew.[4]

Both the bomber and transport versions were to be powered by three Bristol Jupiter IV 9Asb engines of 309–331 kilowatts (414–444 hp), including two tractors and one pusher.[4]