| XP-4 | |
|---|---|
 Boeing XP-4 during trials | |
| General information | |
| Type | Fighter |
| National origin | United States |
| Manufacturer | Boeing |
| Number built | 1 |
| History | |
| First flight | 1927[1] |
| Developed from | Boeing Model 15 |
TheBoeing XP-4 was a prototype Americanbiplanefighter of the 1920s. It was grounded permanently after just 4.5 hours of flight testing.[1]
In 1926, theUnited States Army was very interested in theturbo-supercharger as a way of improving engine performance, and requested that one be added to the last of thePW-9s, and the engine upgraded to a 510 hpPackard 1A-1500. This machine was designated XP-4.[1]
In addition, the basic PW-9 armament of one .50 and one .30 cal.machine guns in the nose were supplemented by two added .30 cal. guns mounted under the lower wing, far enough out to be outside the propeller arc (thus not needing synchronization).[2]
All these modifications added weight, so the lower wing span was extended by 9.5 feet.
The airplane was delivered toWright Field for testing on 27 July 1927, but it quickly became apparent that the Packard engine did not have sufficient power to compensate for the 800 lbs of extra weight, the craft performing more poorly than its predecessor, and the project was quickly abandoned.[1]
Data from Fighters of the United States Air Force[3]
General characteristics
Performance
Armament
Related lists