The+X-15+as+it+appeared+on+its+rollout+day+in+1958.+The+nose-mounted+air+data+boom+was+later+replaced+with+a+ball+nose+that+could+withstand+the+heating+rates+and+low+pressures+of+X-15+flight.+(NASA) Published on June 7, 2016 in North American Aviation, Inc., X-15A Hypersonic Research RocketplaneFull resolution (1000 × 1239) Next → Overhead view of X-15A-1 56-6670 shows teh roceketplane’s overall fineness ratio and short wings. (North American Aviation, Inc.)