The experimental rocket engine for the BI-1 prototype aircraft exploded during a test in Bilimbay, Sverdlovsk Oblast, Russia, spraying nitric acid fuel all over aircraft engineer Arvid Pallo; mechanics saved him from severe burns by quickly dumping him in a tank full of a sodium carbonate solution kept nearby for the very purpose of neutralizing the acid. Test pilot Grigory Bakhchivandzhi was slightly injured as the head of the rocket engine punched into the cockpit.
