What happened
On November 9, 2017, at Carrasco International Airport (SUMU) in Canelones, Uruguay, a maintenance worker was performing inflation procedures on the left nose wheel of a Bombardier CRJ200, registration CX-SDU. During the process, the tire exploded, resulting in serious injuries to the mechanic. Because the aircraft had already been deplaned and had not yet been released for its next flight, the event was classified as an occupational accident rather than an aviation accident or serious incident.
The investigation
The CIAIA investigation, conducted with assistance from a local company, focused on the equipment used during the inflation. The investigation established that the low-pressure gauge experienced a water hammer effect (pressure surge) that exceeded its maximum operating range. While the high-pressure gauge showed some reading errors, both the regulator and the high-pressure gauge were found to be functioning correctly.
Findings
- The primary cause of the tire explosion was the opening of the high-pressure valve (connected to a nitrogen cylinder at 3000 PSI) while the regulator was still open, directing high-pressure gas directly into the tire.
- The low-pressure gauge was damaged beyond its operational limits due to the sudden pressure surge.