What happened
On June 22, 2010, a Mitsubishi MU2B-26A was performing a flight from Eisenach to Zweibrücken with a crew member and one passenger on board. During the approach to runway 21 at approximately 18:55 local time, the pilot notified the Zweibrücken tower of an uncertain nose gear indication. To verify the gear status, the pilot performed a visual inspection and a low pass by the control tower, which revealed that the nose gear was only partially extended and was not locked.
Despite several attempts to fully extend the gear, the mechanism failed to deploy. At approximately 19:09, the pilot elected to land on runway 03. Upon touchdown, the nose gear collapsed, causing the aircraft to skid approximately 360 meters along the runway before coming to a halt. The aircraft sustained heavy damage, including damage to the fuselage skin and pressure bulkhead, while a minor amount of damage was caused to the surrounding area.
The investigation
The BFU examined the aircraft and the landing site to determine the cause of the gear malfunction. Investigators inspected the nose gear assembly and found that the gear could not be manually extended using a hand crank even after the aircraft was lifted. The investigation focused on the mechanical components of the nose gear deployment system.
Findings
- The investigation established that a broken bolt in the nose gear linkage was the primary cause of the incident.
- The broken bolt had become jammed within the deployment mechanism, physically blocking the extension of the nose gear.
- No traces of lubricant were found on the mechanism, which may have contributed to the seizure of the broken component.