Incident
On November 9, 2017, at Carrasco International Airport (SUMU) in Canelones, Uruguay, a mechanic was seriously injured while inflating the left nose wheel tire of a Bombardier CRJ200 (registration CX-SDU). The tire suddenly exploded during the procedure. The aircraft had no passengers on board, as they had disembarked, and the aircraft had not yet been released by maintenance for the next flight. Under national and international regulations, this event was not classified as an aviation accident or serious incident, but rather as a workplace accident.
Investigation
The investigation, conducted by the Uruguayan Aviation Accident and Incident Investigation Commission (CIAIA) with assistance from a local company, determined that the low-pressure gauge experienced a pressure surge exceeding its maximum operating range. The high-pressure regulator and gauge, despite a certain reading error, were functioning correctly.
Probable Cause
The probable cause of the incident was the opening of the high-pressure valve (on the nitrogen tube at 3000 PSI) with the regulator open, allowing high-pressure nitrogen to flow directly to the wheel.