19970512012989A

Accident · Minor damage

FAA accident report · Airbus A300 B4-605R · West Palm Beach, FL · May 12, 1997

Date
May 12, 1997 · 15:29 local
Place
West Palm Beach, FL
Phase of flight
Normal Cruise
Operating rules
Air carrier (Part 121)
Operator
AALA
Damage
Minor damage
Aircraft
N90070
NTSB investigation
NTSBDCA97MA049
Reported as
Airbus A300B4605R
People aboard
163
Fatal injuries
0
Pilot’s flight hours
12,000 total500 in this make and model

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.

(.4) The flight was assigned an airspeed of 230 knots and cleared to descend from FL240 to 16,000 feet in preparation for landing at miami. The FDR indicated that while the autopilot was engaged in the descent, the power levers moved from the mechanical autothrottle limit of 44 degrees to the manual limit of 37 degrees. As the aircraft leveled at 16,000 feet the airspeed decreased. The f/o began a right turn to enter a holding pattern and added some power, which stabilized the airspeed at 178 knots. However, the right bank and the resultant angle of attack (AOA) continued to increase, despite left aileron input by the autopilot. As the autopilot reached the maximum input of 20 degrees, bank angle increased past 50 degrees, and the AOA increased rapidly from 7 degrees to 12 degrees. At this point the stick shaker activated, the autopilot independently disconnected, the power was increased, and full left rudder was used to arrest the roll. The bank angle reached 56 degrees, and the AOA reached 13.7 degrees at 177 knots. The aircraft then pitched down, and entered a series of pitch, yaw, and roll maneuvers as the flight controls went through a period of oscillations for about 34 seconds. The maneuvers finally dampened and the crew recovered at approximately 13,000 feet. One passenger was seriously injured and one flight attendant received minor injuries during the upset. According to wind tunnel and flight test data the A300 engineering simulator should adequately represent the aircraft up to 9 degrees AOA. Unlike the accident aircraft; however, the simulator recovered to wings level promptly when the lateral control inputs recorded by the FDR were used. The roll disagreement between the simulator and accident aircraft began at 7 degrees AOA, and it appears that som effect not modeled in the simulator produced the roll discrepancy. Just prior to the upset the accident aircraft entered a cloud deck. The winds were approximately 240 degrees, 35 knots, and the ambient air temperature was approximately minus 4 degrees c. an atmospheric distrubance aor asymmetric ice contamination were two possible explanation considered, but unproven.

As the FAA filed it

(.4) THE FLIGHT WAS ASSIGNED AN AIRSPEED OF 230 KNOTS AND CLEARED TO DESCEND FROM FL240 TO 16,000 FEET IN PREPARATION FOR LANDING AT MIAMI. THE FDR INDICATED THAT WHILE THE AUTOPILOT WAS ENGAGED IN THE DESCENT, THE POWER LEVERS MOVED FROM THE MECHANICAL AUTOTHROTTLE LIMIT OF 44 DEGREES TO THE MANUAL LIMIT OF 37 DEGREES. AS THE AIRCRAFT LEVELED AT 16,000 FEET THE AIRSPEED DECREASED. THE F/O BEGAN A RIGHT TURN TO ENTER A HOLDING PATTERN AND ADDED SOME POWER, WHICH STABILIZED THE AIRSPEED AT 178 KNOTS. HOWEVER, THE RIGHT BANK AND THE RESULTANT ANGLE OF ATTACK (AOA) CONTINUED TO INCREASE, DESPITE LEFT AILERON INPUT BY THE AUTOPILOT. AS THE AUTOPILOT REACHED THE MAXIMUM INPUT OF 20 DEGREES, BANK ANGLE INCREASED PAST 50 DEGREES, AND THE AOA INCREASED RAPIDLY FROM 7 DEGREES TO 12 DEGREES. AT THIS POINT THE STICK SHAKER ACTIVATED, THE AUTOPILOT INDEPENDENTLY DISCONNECTED, THE POWER WAS INCREASED, AND FULL LEFT RUDDER WAS USED TO ARREST THE ROLL. THE BANK ANGLE REACHED 56 DEGREES, AND THE AOA REACHED 13.7 DEGREES AT 177 KNOTS. THE AIRCRAFT THEN PITCHED DOWN, AND ENTERED A SERIES OF PITCH, YAW, AND ROLL MANEUVERS AS THE FLIGHT CONTROLS WENT THROUGH A PERIOD OF OSCILLATIONS FOR ABOUT 34 SECONDS. THE MANEUVERS FINALLY DAMPENED AND THE CREW RECOVERED AT APPROXIMATELY 13,000 FEET. ONE PASSENGER WAS SERIOUSLY INJURED AND ONE FLIGHT ATTENDANT RECEIVED MINOR INJURIES DURING THE UPSET. ACCORDING TO WIND TUNNEL AND FLIGHT TEST DATA THE A300 ENGINEERING SIMULATOR SHOULD ADEQUATELY REPRESENT THE AIRCRAFT UP TO 9 DEGREES AOA. UNLIKE THE ACCIDENT AIRCRAFT; HOWEVER, THE SIMULATOR RECOVERED TO WINGS LEVEL PROMPTLY WHEN THE LATERAL CONTROL INPUTS RECORDED BY THE FDR WERE USED. THE ROLL DISAGREEMENT BETWEEN THE SIMULATOR AND ACCIDENT AIRCRAFT BEGAN AT 7 DEGREES AOA, AND IT APPEARS THAT SOM EFFECT NOT MODELED IN THE SIMULATOR PRODUCED THE ROLL DISCREPANCY. JUST PRIOR TO THE UPSET THE ACCIDENT AIRCRAFT ENTERED A CLOUD DECK. THE WINDS WERE APPROXIMATELY 240 DEGREES, 35 KNOTS, AND THE AMBIENT AIR TEMPERATURE WAS APPROXIMATELY MINUS 4 DEGREES C. AN ATMOSPHERIC DISTRUBANCE AOR ASYMMETRIC ICE CONTAMINATION WERE TWO POSSIBLE EXPLANATION CONSIDERED, BUT UNPROVEN.

NTSB investigation

The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.

Other reports on N90070 · 2

Matched to the same aircraft by N-number and date.