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20140103000039I

Incident · No damage
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FAA incident report · Beech B200 · Anchorage, AK · January 3, 2014

FAA Aviation Safety Information Portal

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Date
January 3, 2014 · 08:56 local
Place
Anchorage, AK
Airport
Ted Stevens
Phase of flight
Cruise/Level Flight
Operating rules
Air taxi and commuter (Part 135)
Operator
ENHA
Damage
No damage
Aircraft
N24GN
Reported as
Beech B200
Reported engine
Pratt & Whitney PT6 series
People aboard
5
Fatal injuries
0
Other injuries
0
Pilot’s certificates
Airline transport, flight instructor
Pilot’s flight hours
13,834 total6,144 in this make and model53 in the last 90 days
N24GNRegistered now · Beech B200S/N BB-953 · Built 1981Airframe modelBeech B200Engine modelAmateur-built UNKNOWN ENG

From the FAA’s Accident/Incident Data System (AIDS), through its Aviation Safety Information Portal, as reported. The NTSB investigates accidents separately, and its record of an accident is the fuller one. The aircraft is matched to the registry by N-number and event date, checked against the reported make and model; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

What happened

The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.

>>Pilot statement<<

After reaching a cruise altitude of 4000 on an IFR flight the autopilot began to malfunction. The first thing I observed was the command bars on the flight director going out of view and altitude starting to gradually descend. At this point I attempted to correct the altitude. The electric trim started to run nose down and the aircraft started a descent. I attempted to disconnect the autopilot and electric trim with the control switches and the red disconnect switch. None of this had any effect and the aircraft kept trimming nose down as I tried to pull back on the yoke to correct the altitude. With the turbulence and conditions I was unable to reach the autopilot circuit breaker and electric trim circuit breakers. At this point I was unable to stop the descent, but could slow it with back pressure on the yoke. At approximately 2500 feet I regained outside visual references and continued trying procedures to disconnect the electric trim. When all of the procedures had failed I elected to shut off the avionics master switch at approximately 1000 feet this brought me down to an altitude of approximately 500 feet on the descent recovery. Shutting off the avionics master switch disconnected the trim and I was able to

Manually re-trim the aircraft to a positive attitude and contact approach control. I had heard approach control trying to contact me, but due to the nature of the situation and in the interest of safety I chose to control the aircraft first.

As the FAA filed it

>>PILOT STATEMENT<<

AFTER REACHING A CRUISE ALTITUDE OF 4000 ON AN IFR FLIGHT THE AUTOPILOT BEGAN TO MALFUNCTION. THE FIRST THING I OBSERVED WAS THE COMMAND BARS ON THE FLIGHT DIRECTOR GOING OUT OF VIEW AND ALTITUDE STARTING TO GRADUALLY DESCEND. AT THIS POINT I ATTEMPTED TO CORRECT THE ALTITUDE. THE ELECTRIC TRIM STARTED TO RUN NOSE DOWN AND THE AIRCRAFT STARTED A DESCENT. I ATTEMPTED TO DISCONNECT THE AUTOPILOT AND ELECTRIC TRIM WITH THE CONTROL SWITCHES AND THE RED DISCONNECT SWITCH. NONE OF THIS HAD ANY EFFECT AND THE AIRCRAFT KEPT TRIMMING NOSE DOWN AS I TRIED TO PULL BACK ON THE YOKE TO CORRECT THE ALTITUDE. WITH THE TURBULENCE AND CONDITIONS I WAS UNABLE TO REACH THE AUTOPILOT CIRCUIT BREAKER AND ELECTRIC TRIM CIRCUIT BREAKERS. AT THIS POINT I WAS UNABLE TO STOP THE DESCENT, BUT COULD SLOW IT WITH BACK PRESSURE ON THE YOKE. AT APPROXIMATELY 2500 FEET I REGAINED OUTSIDE VISUAL REFERENCES AND CONTINUED TRYING PROCEDURES TO DISCONNECT THE ELECTRIC TRIM. WHEN ALL OF THE PROCEDURES HAD FAILED I ELECTED TO SHUT OFF THE AVIONICS MASTER SWITCH AT APPROXIMATELY 1000 FEET THIS BROUGHT ME DOWN TO AN ALTITUDE OF APPROXIMATELY 500 FEET ON THE DESCENT RECOVERY. SHUTTING OFF THE AVIONICS MASTER SWITCH DISCONNECTED THE TRIM AND I WAS ABLE TO

MANUALLY RE-TRIM THE AIRCRAFT TO A POSITIVE ATTITUDE AND CONTACT APPROACH CONTROL. I HAD HEARD APPROACH CONTROL TRYING TO CONTACT ME, BUT DUE TO THE NATURE OF THE SITUATION AND IN THE INTEREST OF SAFETY I CHOSE TO CONTROL THE AIRCRAFT FIRST.