North American X-15 Prototype No.1 (1:144 scale)
- A whole series of X-series experimental aircraft were made for the US Air Force (USAF). The first was the Bell X-1, but another one that is equally famous is the North American X-15. The rocket-powered X-15 reached the very edge of outer space & today it still holds the world record for the fastest speed attained by a manned rocket-powered aircraft. Its fastest recorded speed was Mach 6.72, equating to 7, 274km/h. This hypersonic spaceplane was produced by North American Aviation & Reaction Motors, the latter manufacturing the XLR-99 rocket engine. A total of three X-15s were made & 199 flight tests were conducted from 1959 to 1968. These flights contributed much to American knowledge about aircraft & spacecraft design. For its flight tests, the 15.45m-long X-15 was carried under the wing of a B-52 operated by NASA, & then released at an altitude of nearly 14km.