The US National Transportation Safety Board (NTSB) has issued an urgent safety recommendation calling for immediate inspections on nearly 1,900 Bombardier Learjet aircraft after a fatal runway accident in Arizona revealed a potentially serious landing gear fault.
The recommendation, directed to the Federal Aviation Administration (FAA), applies to 10 Learjet models currently in service worldwide.
It calls on operators to comply with Bombardier’s service bulletins to verify that the main landing gear are correctly attached to the airframe.
A second recommendation urges the FAA to require Bombardier to revise its maintenance procedures to include a post-maintenance visual check confirming the correct installation of the aft landing gear trunnion pin and retaining bolt.
According to investigators, in the absence of this verification step, a retaining bolt could be installed without passing through the trunnion pin — leaving the gear insecurely attached and at risk of detaching.
The misassembly, the NTSB warned, “is not readily detectable during routine maintenance or pre-flight inspections.”
The warning follows the investigation into the 10 February fatal crash of a Learjet 35A in Scottsdale, Arizona. After touchdown, the aircraft veered off the runway and struck a parked Gulfstream G200. The Learjet’s left main landing gear separated during the accident sequence, and its captain was killed.
The first officer, a passenger, and one person in the Gulfstream were seriously injured.
During the probe, investigators uncovered three earlier incidents — in 1995, 2001 and 2008 — in which Learjet landing gear disconnected from the airframe because of the same issue.
Following the Scottsdale crash, Bombardier issued a service bulletin advising operators to carry out a one-time inspection of the landing gear attachment. However, the NTSB said that only 12% of affected aircraft have so far been checked.
The safety board described its latest call as an “urgent recommendation,” reserved for issues that pose an immediate risk to life or property. Recipients have 30 days to respond.
The FAA and Bombardier have yet to issue public statements in response to the NTSB’s findings.