SIAI p.21
| SIAI p.21 | |
|---|---|
|
|
| Type: | Flying boat |
| Design country: | |
| Manufacturer: | |
| First flight: |
1921 |
| Number of pieces: |
1 |
The SIAI S 21 was a racing flying boat from the Italian aircraft manufacturer SIAI-Marchetti . It was built as a follow-up project to the unsuccessful SIAI S.17 and SIAI S.19 models to win the Schneider Trophy .
history
The previous models SIAI S.17 and SIAI S.19 were supposed to win the Schneider Trophy according to SIAI's plans , but were unsuccessful: The S. 17 crashed into Lake Maggiore , while the S. 19 failed to safely install the engine .
The S. 21 was supposed to take part in a race in Monaco on April 13, 1921 , but suffered a keel damage and could not start. Nevertheless the SIAI S. 21 was registered for the Schneider Trophy 1921. Before the race in August, the pilot fell ill, so that the machine could not start here either and the Schneider Trophy went to another winner. During the training flights, however, the superior technology of the S. 21 was shown.
technology
Like the previous models, the S. 21 was a double-decker flying boat with a canoe-shaped wooden hull. As with the previous machines SIAI S.8 to SIAI S.19 , the wings were covered with ropes and attached to the fuselage with spars and steel wires. At the beginning the S. 21 was equipped with an Isotta Fraschini -V9 engine with 260 HP, for the planned participation in the Schneider Trophy an Ansaldo 4E-14 with 300 HP with a two-bladed propeller was installed. The engine mount was made from steel spars.
The engine of the S. 21 was significantly weaker and smaller than the engine of the previous model, the S. 19. SIAI thus drew the conclusions from the difficulties during installation that caused the S. 19 to fail.
Technical specifications
| Parameter: | Data: |
|---|---|
| span | 6.6 m |
| length | 6.6 m |
| height | 2.9 m |
| Wing area | unknown |
| Empty mass | unknown |
| Takeoff mass | unknown |
| drive | an Ansaldo San Giorgio 4E-14, 300 PS (221 kW) |
| Cruising speed | approx. 170 km / h |
| Top speed | 220 km / h |
| Range | approx. 600 km |
| crew | 1 man |
| Armament | no |
