Boeing XB-15
| Boeing XB-15 | |
|---|---|
 XB-15 on test flight |
|
| Type: | Strategic bomber |
| Design country: | |
| Manufacturer: | |
| First flight: |
October 15, 1937 |
| Commissioning: |
Never put into service |
| Production time: |
Was never mass-produced |
| Number of pieces: |
1 |
The Boeing XB-15 (Model 294) was a heavy bomber of the United States Army Air Corps (USAAC) from 1937, only one prototype was built by the.
development
In 1934 the United States Army Air Corps issued a tender for a heavy bomber with a range of 5,000 miles (8,050 km). The USAAC's first designation for the design was XBLR-1 ( experimental status, bomber, long range, model 1 ). The intended use designation "BLR" was only used in 1935-1936 for only three drafts. Even before the first flight, the name was changed to XB-15 . When the XB-15 flew for the first time on October 15, 1937, it was the largest and most voluminous aircraft that had been built in the USA until then .
It broke a number of records in the area of payload. On July 30, 1939, a record flight of 14,154 kg took place at an altitude of 2500 m. Due to its size, it was possible to move through shafts in the wings, for example to carry out minor engine repairs. Because the airspeed was slow, a 5,000 mile flight took several days. For this purpose there was even a sleeping area for the crew members.
It was planned to install 1000 hp water-cooled engines, but due to the lack of engines, only 850 hp (637 kW) Pratt & Whitney R- 1830-11 radial engines were used. The aircraft was therefore severely underpowered and only reached a top speed of 322 km / h. Since this was far too slow for an acceptable heavy bomber, the project was discontinued. No XB-15 was put into service, instead the prototype was converted to the XC-105 freighter for the USAAC.
Outstanding innovations in the XB-15
- Autopilot
- automatic aircraft de- icing
- Power supply independent of the engines
- Motors can be serviced in flight through service aisles
- Bedroom / lounge and washroom for the crew
- retractable landing gear with double tires
Technical specifications
| Parameter | Data |
|---|---|
| crew | 10 |
| length | 32.6 m |
| span | 45.5 m |
| height | 5.5 m |
| Wing area | 260 m² |
| Empty mass | 30,001 kg |
| Takeoff mass | 37,000 kg |
| drive | 4 × Pratt & Whitney R-1830 -11 with 850 PS (640 kW) each |
| Top speed | 346 km / h |
| Service ceiling | 6,160 m |
| Range | 8,250 km |
| Armament | 3 × 7.7 mm machine guns, 3 × 12.7 mm machine guns, 5,400 kg bombs |
