N24706

HISTORY OF FLIGHT

On April 29, 1993, at 1555 central daylight time, an Embraer EMB-120 RT, Brasilia, N24706, was substantially damaged when it collided with rough terrain during an overrun following a forced landing at the Grider Field airport in Pine Bluff, Arkansas. The forced landing was executed following a stall and loss of control at 17,412 feet during climb which resulted in damage to the left engine and propeller. The airplane, owned by Continental Airlines, Inc., operated by Continental Express, Inc., was using the call sign of Jet Link flight 2733. It was flown by two ATP rated pilots, on a 14 CFR Part 135 scheduled passenger flight from Little Rock, Arkansas, to Houston, Texas. An Instrument Flight Rules (IFR) plan was filed and in effect and visual meteorological conditions (VMC) prevailed at the accident site. Instrument meteorological conditions (IMC) prevailed during the loss of control, descent, and recovery. Of the three crewmembers and twenty seven passengers aboard, the flight attendant and twelve passengers received minor injuries, while the two flightcrew members and remaining fifteen passengers were not injured.

The flight departed the gate at Little Rock, on time, and received takeoff clearance on runway 22R, en route to Houston's Intercontinental Airport, at 1516:00. After a normal takeoff and initial climb, the flight contacted Little Rock Departure Control and was instructed to join the J-180 airway and maintain 10,000 feet. At 1522:09, the flight was handed off to Memphis Air Route Traffic Control Center (ARTCC). Upon contacting the center, the crew reported climbing through 7,500 feet and was instructed to climb and maintain flight level (FL) 220. The cockpit voice recorder (CVR) then recorded a conversation between the captain and the first officer in which they discussed the performance data for a climb to FL260. It was noted on the tape that the captain said "I don't care" in response to a question from the first officer regarding what final altitude the captainwanted for cruise. During this exchange, at 1522:54, while the airplane was passing through about 8,000 feet, the CVR recorded the voice of the flight attendant saying "Hi." Non-pertinent conversation between the flightcrew followed for about one minute. At 1526:26, Memphis Center instructed the flight to continue the climb and gave a final cruise altitude of FL230. The first officer, who was handling the radios, requested and was given FL220 as a final altitude. That was the last radio contact between the flight and air traffic control (ATC) prior to the loss of control. At 1528:49, the flight attendant again entered the flight deck and began a conversation with the captain that lasted until the time of the loss of control at 1533:16, four minutes and twenty seven seconds later. The crew discussed using the windshield wipers to remove something from the wind screen. They later said they were talking about bugs. At 1530:52, the flight attendant requested that the captain "climb faster" as she wanted to begin cabin service and she could not drag the beverage cart "uphill" during the climb. The captain agreed and subsequently said, "Okay we'll try to get up a little more" and "yeah we're almost there another six thousand feet another six minutes." This exchange was followed by non-pertinent conversation between the captain and the flight attendant, during which the first officer commented that they were not climbing very fast. The captain replied, "heavy really heavy" and continued with the conversation. At 1533:11, the captain interrupted the conversation with the flight attendant and said, "Frank hang on something ain't right." This was followed by the sound of the autoflight system disconnect at 1533:16.3, and stick shaker activation at 1533:16.8. At 1533:18, the aural stall warning activated and the captain said, "airspeed." The stick shaker and aural stall warning continued until the end of the recording at 1533:46.7. At 1533:22.7, the captain again said "hang on" and at 1533:24.6, the first officer said, "power up power's." This was followed by increasing engine noise at 1533:25.6 and the beginning of vibrations through the airframe at 1533:34.7. At 1533:39.7, the engine noise decreased and was then no longer heard. At 1534:26, Memphis Center attempted, unsuccessfully, to hand off flight 2733 to Fort Worth Center and at 1534:50, flight 2733 contacted Memphis Center and declared an emergency, stating they had "lost an engine and needed to put her down."

The captain stated that immediately prior to the loss of control, he noticed the ball was slewed full left and the rudder trim wheel was trimmed 10 units right, its full limit. According to the digital flight data recorder (DFDR) data, the onset of the loss of control was characterized by an initial constant right yaw with left yoke displacement and then several oscillating bank angles to the right and left that increased in rate and angle severity until the airplane stalled and entered a post-stall gyration. The airplane continued in the gyration for one rotation to the left and then stabilized in a nose down oscillating attitude. Roll oscillations in excess of 111 degrees and pitch attitude values in excess of 67 degrees aircraft nose down were recorded prior to and during the loss of control and descent. Recovery was initiated after the first officer lowered the landing gear. The airplane subsequently entered a secondary stall during the recovery at about 6,700 feet and ultimately returned to controlled flight at 5,500 feet. The loss of control, descent, and recovery all occurred in instrument meteorological conditions (IMC).

The yoke position channel of the DFDR indicated that it was never pushed forward during or following the initial oscillations of the airplane at the beginning of the loss of control. The data also indicated that the control inputs to correct the roll oscillations were out of phase with what the airplane was actually doing throughout most of the recovery. The roll corrections did not phase with the airplane until several seconds after the post-stall gyration completed one revolution and the yoke was never pushed forward. The DFDR and flight data acquisition unit (FDAU) data also indicated that following the initial recovery, the airplane entered a nose high, steep left bank attitude which was maintained until a secondary stall was entered. Control movements during the second recovery were more coordinated than during the first.

Following recovery, the crew contacted Memphis Center, declared an emergency and requested vectors to the nearest airport, stating that they could not maintain level flight. The crew was offered several airports as options and selected Pine Bluff. The captain stated that he ordered the left engine shut down during the descent; he thought he had experienced an over speed on that engine. Following the recovery, the captain noticed the left engine was missing three of the four propeller blades, all of the upper cowlings, and was displaced in the mounts. The crew stated that the airplane would fly at an airspeed of about 125 knots, before the stick shaker activated, and maintain a rate of descent that varied from zero to 500 feet per minute. The crew further stated that they had difficulty turning the airplane to the right.

The airplane broke out of IMC close in to the airport. The captain stated that he overshot the right turn to final due to controllability problems and the airplane touched down with 1,880 feet of wet runway remaining. The captain further stated that he applied the brakes at touchdown and the airplane immediately began hydroplaning and went off the departure end of runway 17, onto wet rough sod, avoiding a vehicle and construction personnel. Tracks found on the runway were consistent with hydroplaning. After passing between the ILS antenna and the ILS equipment building, the airplane came to rest in a rice field, 687 feet from the end of the runway. The crew and passengers immediately evacuated the airplane. The right engine could not be shut down by the crew or aircraft rescue and fire fighting (ARFF) personnel and continued to run in a pool of Jet A fuel for about 15 minutes.

WITNESSES

In addition to the crewmembers, statements were obtained from passengers, other pilots, ground witnesses, and air traffic control personnel who were in contact with the flight. Twenty six of the twenty seven passengers responded with written statements, while the other one was contacted directly and her observations obtained. Five pilots were identified that were flying through the same airspace as flight 2733. Four were interviewed by telephone and one provided a written statement. Additionally, seven statements were obtained from the air traffic controllers and six statements were received from ground witnesses located at the Pine Bluff airport.

Several of the passengers commented on the smoothness and lack of turbulence on the flight, up to the beginning of the loss of control. Two specifically noted that they did not observe any lightning or hear thunder. A few characterized the onset of the event as a shudder through the airframe and associated it with turbulence. Some remembered the airplane initially banking left, then right, then left again with greater violence. Others had the sequence reversed. One passenger commented that he observed a whitish substance that appeared to be "snow" on the windshield and another commented that the takeoff roll at Little Rock, appeared to take longer than he was used to in similar airplanes. The passenger seated in the front row, seat 1B, stated that during the climb, she observed the captain put his seat back, unbuckle his seat belt and put his foot up on the console. She further said, "I watched the pilot (captain) turning a wheel which I think made us turn to the right. He kept turning a knob it looked like for balance." A majority of the passengers recalled the flig...