Investigation Summary
The flight was a scheduled commuter service operated by Executive Air Charter (doing business as American Eagle). During the approach to Mayagüez, the aircraft, N355CA, encountered heavy rain and cloud cover. A witness on the ground reported hearing the distinct sound of propellers entering reverse pitch before the aircraft emerged from the clouds in a steep, nose-low attitude. Data from the Cockpit Voice Recorder (CVR) indicated an abrupt change in engine frequency and amplitude approximately 10 seconds before impact. Post-crash examination of the left engine beta indicator lamp showed evidence of illumination at the time of impact, confirming the propellers had entered the beta range. While the electrical lockout solenoid functioned normally during testing, the mechanical rigging could not be verified due to impact damage. Crucially, a fleet-wide inspection following the crash revealed that three out of eight other CASA 212 aircraft in the operator's fleet had inoperative beta blocking devices, highlighting a systemic lack of functional testing requirements for this critical safety system.
Final Conclusions
The National Transportation Safety Board (NTSB) determined the probable cause to be the failure of the beta blocking device for undetermined reasons, combined with the second pilot's inadvertent activation of the power lever(s) aft of the flight idle position and into the beta range, resulting in a loss of airplane control.
Video Analysis
No video analysis linked for this case file yet.
Airframe & Maintenance
Crew Experience
Captain
Alton Emmanuel Leslie, 31, of Charlotte Amalie, St. Thomas.
Systems & Failure Modes
Beta Blocking Device
A mechanical and electrical safety system designed to prevent the power levers from being moved into the beta (reverse) range during flight, which would cause a catastrophic loss of lift and control.
Beta Indicator Lamp
A cockpit light that alerts the crew when the propellers have entered the beta range; forensic analysis of this lamp confirmed the system was active at impact.
Interesting Facts
- 01The aircraft was a CASA C-212 Aviocar 200, serial number 234, manufactured in 1982.
- 02The aircraft had 14,135 total flight hours at the time of the accident.
- 03Post-crash inspection of the operator's remaining CASA 212 fleet found 3 of 8 aircraft had inoperative beta blocking devices.
- 04Neither the manufacturer nor the operator had a requirement for periodic functional testing of the beta blocking system.
- 05The left engine beta indicator lamp showed oxide deposits and stretched coils, proving it was lit during the crash.
- 06The accident occurred in heavy rain conditions during a visual approach.
Safety Actions & Advisories
Fleet Functional Testing
Following the accident, the operator conducted functional tests of the electrical and backup beta blocking devices on its remaining CASA 212 fleet, identifying multiple inoperative units.