Half a century ago, shockwaves in miniature
From little things, fast things grow.
NASA test pilots are justly famed for their bravery, but before prototype planes are built, their response to the brutal physics of high-speed flight is modelled exhaustively at smaller scales.
In this image, taken in March 1962, shock waves can be seen breaking across a miniature X-15 hypersonic rocket-powered aircraft. The model was set up inside in the Supersonic Pressure Tunnel built at NASA’s Langley Research Centre in the US.
Full-size X-15s went on to set speed and altitude records. In October 1967, one piloted by William Knight reached 31,120 metres above the Earth and hit a top speed of 7274 kilometres per hour.