NTSB Identification: LAX06CA217.
The docket is stored in the Docket Management System (DMS). Please contact Records Management Division
Accident occurred Tuesday, June 27, 2006 in El Cajon, CA
Probable Cause Approval Date: 10/03/2006
Aircraft: Beech 76, registration: N6720T
Injuries: 2 Uninjured.

NTSB investigators used data provided by various entities, including, but not limited to, the Federal Aviation Administration and/or the operator and did not travel in support of this investigation to prepare this aircraft accident report.

The airplane's left main landing gear collapsed during the landing rollout. After performing maneuvers in the practice area, the flight instructor and student proceeded to a nearby airport to practice touch-and-goes. As they approached the airport traffic pattern, the student pilot moved the gear selector to the down position. Once the gear was down they noticed that the left main gear down light was not illuminated. They recycled the landing gear, but still received the same indication. A low approach and flyby past the tower confirmed that the gear was in the down position. The instructor decided to return to his home airport instead of landing at this airport. While en route, the instructor and student inspected the light bulbs of the indicator light and found them to be operating properly. They recycled the gear one more time. While doing this, the gear motor circuit breaker popped, and they smelled smoke in the cockpit. They pulled the landing gear circuit breakers immediately and the smoke smell cleared. The pilots extended the landing gear using the manual extension checklist. Once the gear came down, they still had the same unsafe gear indication. The instructor yawed the airplane in an attempt to lock the gear, but received the same unsafe indication. Upon arriving at his home airport, the instructor touched down using a soft-field landing technique. As the airplane decelerated, the left main landing gear collapsed and the left wing tip and the propeller struck the runway. Federal Aviation Administration inspectors examined the main landing gear after the accident. They found the left main landing gear "A" frame tube had failed. Airworthiness Directive 97-06-10 requires repetitive inspection of the main landing gear "A" frame assemblies for cracks and lubrication, and requires the replacement of any assembly found cracked. The actions specified in this AD are intended to prevent main landing gear failure and collapse because of a cracked "A" frame assembly. A review of the aircraft records indicated that AD 97-06-10 had been complied with during the last 100-hour inspection on June 21, 2006. This aircraft is operated by a flight school and the maintenance records show that it is operated at an activity level where a 100-hour inspection is accomplished once every 30 days or so.

The National Transportation Safety Board determines the probable cause(s) of this accident to be:

the failure of the "A" frame tube, which caused the left main landing gear to collapse.

Full narrative available

Index for Jun2006 | Index of months