Panama City

The two commercial pilots were conducting a personal, cross-country flight. A video surveillance camera at the airport captured their airplane’s approach. Review of the video revealed that, as the airplane approached the approach end of the landing runway, it began to climb, rolled left, became inverted, and then impacted terrain. The left thrust reverser (T/R) was found open and unlatched at the accident site. An asymmetric deployment of the left T/R would have resulted in a left roll/yaw. The lack of an airworthy and operable cockpit voice recorder, which was required for the flight, precluded identifying which pilot was performing pilot flying duties, as well as other crew actions and background noises, that would have facilitated the investigation. Postaccident examination of the airplane revealed that it was not equipped, nor was required to be equipped, with a nose landing gear (NLG) ground contact switch intended to preclude inflight operation of the thrust reverser (T/R). The left T/R door was found unlatched and open, and the right T/R door was found closed and latched. Further, electrical testing of the T/R left and right stow microswitches within the cockpit throttle quadrant revealed that the left stow microswitch did not operate within design specifications. Disassembly of the left and right stow microswitches revealed evidence of arc wear due to aging. Based on this information, it is likely that the airplane’s lack of an NLG ground contact switch and the age-related failure of the stow microswitches resulted in an asymmetric T/R deployment while on approach and a subsequent loss of airplane control. Also, there were additional T/R system components that were found to unairworthy that would have affected the control of the T/R system. Operational testing of the T/R system could not be performed due to the damage the airplane incurred during the accident. Toxicology testing results of the pilot’s specimens indicated that the pilot had taken diazepam, which is considered impairing at certain levels. However, the detected amounts of both diazepam and its metabolite nordiazepam were at subtherapeutic levels, and given the long half-life of these compounds, it appears that the medication was taken several days before the accident; therefore, it is unlikely that the pilot was impaired at the time of the accident and thus that his use of diazepam was a not factor in the accident.

The airline transport pilot delayed his scheduled departure for the night cargo flight due to thunderstorms along the route. Before departing, the pilot explained to the flight follower assigned to the flight that if he could not get though the thunderstorms along the planned route, he would divert to the alternate airport. While en route, the pilot was advised by the air traffic controller in contact with the flight of a "ragged line of moderate, heavy, and extreme" precipitation along his planned route. The controller also stated that he did not see any breaks in the weather. The controller cleared the pilot to descend at his discretion from 7,000 ft mean sea level (msl) to 3,000 ft msl, and subsequently, the controller suggested a diversion to the northeast for about 70 nautical miles that would avoid the most severe weather. The pilot responded that he had enough fuel for such a diversion but concluded that he would "see what the radar is painting" after descending to 3,000 ft msl. About 1 minute 30 seconds later, as the airplane was descending through 7,000 ft msl, the controller stated, "I just lost you on radar, I don't show a transponder, it might have to do with the weather." About 40 seconds later, the pilot advised the controller that he intended to deviate to the right of course, and the controller told the pilot that he could turn left and right as needed. Shortly thereafter, the pilot stated that he was going to turn around and proceed to his alternate airport. The controller cleared the pilot direct to his alternate and instructed him to maintain 3,000 ft msl. The pilot acknowledged the instruction, and the controller then stated, "do you want to climb back up? I can offer you any altitude." The pilot responded that he would try to climb back to 3,000 ft msl. The controller then recommended a heading of 180° to "get you clear of the weather quicker," and the pilot responded, "alright 180." There were no further communications from the pilot. Shortly thereafter, radar data showed the airplane enter a right turn that continued through about 540°. During the turn its airspeed varied between 198 and 130 knots, while its estimated bank angles were between 40 and 50°. Examination of the wreckage indicated that airplane experienced an in-flight breakup at relatively low altitude, consistent with radar data that showed the airplane's last recorded altitudes to be around 3,500 ft msl. The symmetrical nature of the breakup, damage to the outboard wings, and damage to the upper fuselage were all signatures indicative that the left and right wings failed in positive overload almost simultaneously. All of the fracture surfaces examined had a dull, grainy appearance consistent with overstress separation. There was no evidence of pre-existing cracking noted at any of the separation points, nor was there evidence of any mechanical anomalies that would have prevented normal operation. Review of base reflectivity weather radar data showed that, while the pilot was maneuvering to divert to the alternate airport, the airplane was operating in an area of light precipitation that rapidly intensified to heavy precipitation, as shown by radar scans completed shortly after the accident. During this time, the flight was likely operating in clouds along the leading edge of the convective line, where the pilot most likely would have encountered updrafts and severe or greater turbulence. The low visibility conditions that existed during the flight, which was conducted at night and in instrument meteorological conditions, coupled with the turbulence the flight likely encountered, were conducive to the development of spatial disorientation. Additionally, the airplane's maneuvering during the final moments of the flight was consistent with a loss of control due to spatial disorientation. The pilot's continued flight into known convective weather conditions and his delayed decision to divert the flight directly contributed to the accident. Although the operator had a system safety-based program, the responsibility for the safe outcome of the flight was left solely to the pilot. Written company policy required completion of a flight risk assessment tool (FRAT) before each flight by the assigned flight follower; however, a FRAT was not completed for the accident flight. The flight followers responsible for completing the FRATs were not trained to complete them for night cargo flights, and the operator's management was not aware that the FRATs were not being completed for night cargo flights. Further, if a FRAT had been completed for the accident flight, the resultant score would have allowed the flight to commence into known hazardous weather conditions without any further review. If greater oversight had been provided by the operator, it is possible that the flight may have been cancelled or re-routed due to the severity of the convective weather conditions present along the planned route of flight.

Few minutes after he departed Isla del Rey Airport, while overflying the bay of Panama City, the pilot informed ATC about engine problems. Unable to reach Panama City-Marcos A. Gelabert Airport, the pilot reduced his altitude and elected to make an emergency landing on the Perico Island, some 10 km south of Panama City Airport. After touchdown, the aircraft rolled for few dozen metres before coming to rest against a container. All eight occupants escaped uninjured while the aircraft was damaged beyond repair.

Shortly after takeoff from Panama City-Marcos A. Gelabert Airport, while climbing, the crew encountered technical problem with the engine and declared an emergency. He realized he could not return to his departure point so he attempted an emergency landing on a road when the aircraft struck a tree and crashed 9 km weat of the airport. All seven occupants escaped uninjured while the aircraft was damaged beyond repair.

The pilot received a preflight briefing from the Gainesville Automated Flight Service Station before departing on the instrument flight. The briefer advised the pilot of the potential for occasional moderate turbulence between 24,000 and 37,000 feet and on the current Convective SIGMET for embedded thunderstorms over southern Mississippi. The flight was in cruise flight at 24, 000 feet when the airplane encountered moderate to severe turbulence and heavy rain. The airplane descended from 24,000 feet to 3,100 feet in a descending right turn in 2 minutes and 10 seconds before radar contact was lost. The airplane was located 8 hours 26 minutes after the accident along a crash debris line that extended between 1.31 miles and 1.53 miles northwest of Arlington, Alabama. Airframe components recovered from the accident site were submitted to the NTSB Materials laboratory for examination. The examinations revealed all failures were consistent with overstress fracturing and there was no evidence of pre-existing conditions or fatigue damage. Examination of the airframe revealed that the airframe design limits were exceeded. The Pilot's Operating Handbook states the maximum structural cruising speed is 173 knots indicated airspeed or 170 knots calibrated airspeed. The co-pilot airspeed indicator at the crash site indicated 180 knots calibrated airspeed. The design maneuvering speed is 135 knots indicated airspeed or 133 knots calibrated airspeed.

The DC-3 experienced an in-flight engine fire, and made a forced landing at nearby airport, following the separation of the right engine assembly from the airframe. According to the pilot, during cruise flight, at 5000 feet, he heard a loud "bang" and saw a reflection of fire on his left engine nacelle. Fire damage was found on the trailing edge of the right wing and on the landing gear assembly. The engine examination also showed that No. 12 cylinder had separated from the main case. Evidence of oil from the No. 12 cylinder was found across engine and exhaust systems. Further examination revealed Nos. 7, 8 and 9 cylinders also failed and separated, and the engine seized and separated from the airframe.

Crashed in unknown circumstances near Panama City Airport. There were no casualties. The accident occurred somewhere in August 1996 (exact date unknown).

The flight had been cleared for the VOR-A approach, with instructions to circle to a right downwind and land on runway 14. The tower controller observed the airplane emerge from the overcast over runway 23 abeam the VOR, then make a tight right turn onto the downwind leg, parallel to runway 14 and close in. When the airplane was abeam the runway 14 threshold, she observed the nose pitch up, and the airplane did what she described as a wing over. It then dove and impacted the runway near the threshold. The controller stated that the pilot made this round trip every day, and she had seen him do this maneuver on several occasions. The pilot, sole on board, was killed.

En route from Panama City to El Porvenir Island, four hijackers forced to crew to change his itinerary and to fly to Turbo, Colombia. The aircraft force landed in a remote airstrip where all four hijackers disembarked and disappeared. All other occupants were injured and the aircraft did not return into service.

Witnesses described the takeoff as a long ground roll, slow climb, and engines not sounding normal. The airplane then settled into trees. Teardown of the left engine revealed water present in the fuel injector lines of #1, #3 and #5 cylinders. #3 nozzle plugged. Intake valves dark and sooty. Pistons 1, 3 and 5 had considerable amounts of dark carbon deposits. Teardown of right engine revealed extensive carbon buildups throughout. An engine test run was performed by the director of maintenance day before accident. Personnel formerly employed by the operator provided written statements of allegations pertaining to the general condition of company airplanes, falsification of maintenance records, and improper maintenance procedures being performed on company airplanes. Both occupants were killed.