Low-Altitude Maneuvering · NTSB WPR12LA407
MOORE EDWARD R MXS — Borrego Springs, CA
| Date | September 8, 2012 |
| Location | Borrego Springs, CA |
| Aircraft | MOORE EDWARD R MXS (amateur-built) |
| Purpose of flight | Personal |
| Conditions | Day · Visual Meteorological Cond |
| Phase / occurrence | Maneuvering-aerobatics Loss of control in flight |
| Pilot age | 58 |
| Pilot total time | 4,500 hrs · High time |
| Time in type | 1 hrs |
| Fatalities | 1 |
Probable cause
NTSB findings
- Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Pitch control-Attain/maintain not possible - C
- Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Lateral/bank control-Attain/maintain not possible - C
- Personnel issues-Task performance-Maintenance-Modification/alteration-Other/unknown - F
- Aircraft-Aircraft structures-(general)-(general)-Malfunction - F
- Aircraft-Aircraft systems-Flight control system-(general)-Failure - C
What happened
During the aerobatic practice flight, the airplane departed controlled flight. The pilot opened the canopy, which then separated from the airplane, and exited the airplane. Due to the low altitude, the pilot's parachute did not fully deploy before he impacted the ground.
The accident airplane was 1 of 14 MX-model airplanes. It was the only model built from a kit as an experimental, amateur-built aircraft, and it was constructed differently than the other MX-model airplanes. Postaccident examination of the torque tube assembly revealed that the forward bulkhead holding the torque tube assembly in place was constructed in a way that allowed the bulkhead to flex, which subsequently led the torque tube assembly to detach from the forward bearing during the accident flight and resulted in the loss of aileron and elevator control. Examination also revealed that the forward and aft bearing houses were installed opposite of the correct direction, which allowed the bearings to detach from the torque tube assembly when the front bulkhead flexed.