An Unfortunate Accident
The X-2 was created to fly at Mach and also to address the difficulties of its predecessor, the X-1 encountered. The jet featured swept wings angled backward to reduce the shockwave that forms when the plane transitions from subsonic to supersonic speeds.
It also pushed the US’ understanding of rocket engines. It also set speed and altitude records, but not without difficulty. Shortly after the first pilot reached Mach 3, the plane lost control. The pilot managed to eject in the plane’s escape capsule but was likely knocked out in the process and wasn’t able to deploy his parachute in time.
Thankfully, we’re not in the 1950s anymore and personal parachutes are self-deploying these days!