NTSB Factual Report

HISTORY OF FLIGHT

On December 5, 2016, about 2222 eastern standard time, a Fairchild SA-227AC, N765FA, operating as Key Lime Air flight 308 (LYM308), was destroyed following an in-flight breakup near Camilla, Georgia. The airline transport pilot was fatally injured. The airplane was registered to CBG LLC., and operated by Key Lime Air as an on-demand cargo flight conducted under the provisions of Title 14 Code of Federal Regulations Part 135. Night instrument meteorological conditions prevailed, and an instrument flight rules flight plan was filed. The flight originated about 2154 from Northwest Florida Beaches International Airport (ECP), Panama City, Florida, and was destined for Southwest Georgia Regional Airport (ABY), Albany, Georgia.

About 1 hour before the scheduled departure time of 2130, the pilot completed a routine check-in call with the Key Lime Air flight follower assigned to cargo flights, who was one of two flight followers working the night of the accident at the operator's headquarters and dispatch office in Englewood, Colorado; the departure time and weather conditions were discussed. According to the cargo flight follower, the pilot told him that he was "holding on the ground" for convective activity that was "extreme" and had "tornado activity." The pilot delayed the departure to continue to evaluate the weather conditions along his route.

According to an email from the other flight follower on-duty in the dispatch office, about 2140, the customer (UPS) called the operator's dispatch office, wanting to confirm that flight LYM308 would depart, noting if it didn't depart soon, the cargo would "not make service." About 2 minutes later, the other flight follower, who was not assigned to the cargo flights, called the pilot, informing him that UPS had called the dispatch office to ask whether the flight was going to depart. According to this non-cargo flight follower, the pilot explained that he would be departing immediately and would try to fly the clear weather corridor extending northeast toward ABY. The pilot added that if he couldn't get through the storms to his left, he would make Tallahassee International Airport (TLH), Tallahassee, Florida, his alternate. The flight departed about 12 minutes later at 2154.

Review of air traffic control (ATC) voice communication transcripts provided by the Federal Aviation Administration (FAA) revealed that, at 2215, the air traffic controller working the flight, who was located at the Jacksonville Air Route Traffic Control Center, advised the pilot of a "ragged line of moderate, heavy, and extreme precipitation" along his planned route of flight to ABY. The air traffic controller also stated, "I don't show any breaks [in the weather]." The controller then cleared the pilot to descend at his discretion from 7,000 ft mean sea level (msl) to 3,000 ft msl.

Subsequently, the air traffic controller suggested a route of flight that would have required a diversion to the northeast for 70 nautical miles to avoid the most severe weather. The pilot responded that he had enough fuel for such a diversion but that he would "see what the radar is painting" after completing the descent to 3,000 ft msl.

About 1 minute 30 seconds later, at 2218, during the airplane's descent from 7,000 ft msl to 3,000 ft msl, the air traffic 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 the course, and the air traffic controller told the pilot that he could turn left and right as needed. Shortly thereafter, the pilot stated, "we're going to turn back around to Tallahassee." The air traffic controller cleared the pilot direct to TLH and instructed him to maintain 3,000 ft msl. The pilot responded, "present position direct Tallahassee and we'll try to maintain 3,000 here." The air traffic controller then stated, "do you want to climb back up? I can offer you any altitude," and the pilot responded, "we'll see if we can get it up to about 3,000." The air traffic controller then recommended a heading of 180° to "get you clear of the weather quicker," and the pilot responded with "alright 180." There were no further communications from the pilot.

About 2220, radar data showed the airplane enter a right turn that continued through about 540° before radar contact was lost at 2222:24. Throughout the final turn, the airplane's reported altitude was near 3,500 ft. A computational study of the airplane's radar track revealed that its calibrated airspeed varied between 198 and 130 knots, with estimated bank angles between 40 and 50°. The airplane's calculated load factor for this radar-recorded portion of the flight was about 1.3g.

PERSONNEL INFORMATION

The pilot reported at his most recent medical examination on September 29, 2016, that his total flight experience was 11,133 hours. The operator provided the following additional information regarding the pilot's flight experience:

Total time in make & model (SA-227): 4,670 hours

Pilot-in-command time in make and model (SA-227): 4,647 hours

Total time in make & model (SA-227), past 90 days: 74 hours

Total time in make & model (SA-227), past 30 days: 29 hours

Total time in make & model (SA-227), past 24 hours: 0 hours

The pilot's training record began with a satisfactory initial pilot-in-command Part 135 airman competency/proficiency check for the SA-227 airplane, which was completed on November 3, 2008. His most recent Part 135 airman competency/proficiency check was completed on June 29, 2016, in an SA-227AC airplane. According to the company record, the June 2016 check met the requirements of 14 CFR 135.293 (initial and recurrent pilot testing), 135.297 (instrument proficiency), and 135.299 (pilot in command: line checks: routes and airports). From 2008 to 2016, the records revealed no unsatisfactory competency/proficiency checks. The records indicated that the pilot was qualified and current to act as pilot-in-command for the flight.

According to the operator, since 2008, the pilot's primary flight assignment was to operate the single-pilot cargo flight between ECP and ABY (LYM308) and the return flight from ABY to ECP. He was the sole Key Lime Air pilot based at ECP. The flight was scheduled to depart every weekday, Monday through Friday, at 2130 EST. Upon arrival at ABY, the pilot would typically spend the night at the airport and return to flight duty at 0730 to complete the return flight.

According to the pilot's flight duty record, his most recent flight duty ended on December 3, 2016, at 0830. The pilot was off-duty until he checked in with Key Lime Air Dispatch about 1 hour before the accident flight.

AIRCRAFT INFORMATION

The airplane was manufactured in 1990 and was a twin-engine, propeller-driven, low-wing, pressurized airplane originally equipped to carry 19 passengers. The airplane was of all metal construction, had a cruciform tail, and was equipped with a retractable tricycle landing gear system. The airplane was powered by two Honeywell turboshaft model TPE331-11U-611 engines and had a maximum takeoff weight of 16,000 lbs. The airplane was 59.35 ft long, had a wingspan of 57 ft and a tail height of 16.66 ft, and was configured to carry only cargo. A review of copies of maintenance logbook records showed a continuous airworthiness inspection was completed on September 16, 2016. At the time of inspection, the recorded airframe time was 23,233.2 total hours. When the accident occurred, the airplane had flown 63 hours since that inspection.

METEOROLOGICAL INFORMATION

Synoptic Conditions

The National Weather Service (NWS) surface analysis chart for 2200 depicted a low-pressure system over Louisiana at 1004 hectopascals (hPa). The low-pressure system was located along a frontal wave with a cold front extending southward into the Gulf of Mexico and a stationary front extending eastward along the Gulf coast into the Florida panhandle and southern Georgia then into the Atlantic Ocean. A high-pressure system at 1020 hPa was located over North Carolina. The stationary front was depicted over the flight route and near the accident site.

The station models generally depicted an easterly wind flow north of the stationary front and southerly winds south of the front. However, the station models in the immediate area surrounding the accident site showed a cyclonic or counterclockwise wind flow pattern suggesting that a low-pressure area was developing along the stationary front. The surrounding stations also reported moderate to heavy rain and thunderstorms. The station model for Albany, Georgia, reported wind from the north about 10 knots, moderate rain, overcast cloud cover, and a temperature and dew point of 60° Fahrenheit (F). To the south of the front over the Florida panhandle, southerly winds of 10 to 15 knots were indicated with temperatures and dew points in the 70s.

National Composite Radar

The NWS national composite radar image archive for 2220 showed that the accident site was located along the leading edge of a line of convection with reflectivities ranging from 50 to 60 decibels (dBZ) immediately west of the site. The line extended from the Gulf of Mexico immediately west of Panama City, Florida, northeastward to the cities of Albany, Vidalia, and Statesboro, and then eastward through Savannah, Georgia, and into the Atlantic. Other, more scattered or less organized areas of echoes were located across northern Florida, south and east of Tallahassee, to the west of Jacksonville, and into southeastern Georgia. A narrow corridor clear of echoes extended from Panama City to Tallahassee to Moultrie, Georgia. This corridor was located immediately east of the accident site.

Convective Outlook Discussion

The NWS Storm Prediction Center (SPC) graphic convective outlook issued at 2000 depicted where organized thunderstorms were expected to develop and the potential for severe thunderstorms during the period. The chart depicted a slight risk of severe thunderstorms over extreme southeast Louisiana and Mississippi, southern Alabama, southwest Georgia, and the Florida panhandle, which included the accident site. A marginal risk of thunderstorms surrounded the area and included southern Alabama and Georgia and northern Florida. The slight-risk area implied that an area of organized scattered severe storms was possible, with either short-lived and/or not widespread, isolated intense storms possible. It also implied that one or more tornadoes, reports of intense winds, and 1-inch and possible 2-inch hail were expected within the designated area.

Destination Airport Surface Observations

The automated special observation at ABY at 2221 included wind from 090° at 13 knots, visibility 8 statute miles in rain, clouds scattered at 2,600 ft agl and broken at 12,000 ft agl, temperature and dewpoint 16°C, and altimeter 29.81 inches of mercury.

Diversion Airport Observations

The automated special observation at TLH at 2234 included wind from 190° at 16 knots, visibility 10 statute miles in rain, clouds broken at 800 ft agl and overcast at 1,200 ft agl, temperature 24°C, dewpoint 23°C, and altimeter 29.93 inches of mercury.

Weather Radar Imagery

The closest Weather Surveillance Radar-1988, Doppler (WSR-88D) to the accident site was from the NWS Tallahassee (KTLH) location about 50 miles south of the accident site. Based on the radar height calculations, the 0.5° elevation scan depicted the conditions

encompassing the altitudes between 1,960 to 7,000 ft during the minutes of the flight prior to the accident. This was determined to be the most representative of the conditions encountered during the period associated with the accident (for more information see the Meteorology Group Chairman's Factual Report contained in the public docket for this investigation).

The KTLH WSR-88D base reflectivity image for the 0.5° elevation scan at 2221:47 (see Figure 1) showed the accident flight as it tracked along the leading edge of a line of heavy-intensity echoes, and operating in echoes of 5 to 20 dBZ, or light intensity precipitation. The next base reflectivity image for the 0.5° elevation scan at 2228:12 showed rapidly-developing echoes over the preceding flight track (which ended at 2222:24 in the vicinity of the accident site), with intensities of up to 43.5 dBZ or heavy-intensity precipitation.

The base reflectivity image for the 0.5° elevation scan at 2234:39 continued to show echoes increasing in intensity over the accident site with reflectivity values between 40 and 52 dBZ, or heavy to extreme intensity. Several small bowing segments were also indicated to the southwest.

The KTLH WSR-88D echo tops product for 2221 and 2228 showed echo tops near 30,000 to 35,000 ft over the last four minutes along the flight track and the accident site, with echo tops to 45,000 ft immediately west of the accident site.

FLIGHT RECORDERS

The airplane was equipped with a Fairchild A-100A cockpit voice recorder (CVR). The exterior of the CVR sustained structural damage. The magnetic tape was retrieved from within the crash-protected case and was successfully read out, with minor distortion audible in limited portions of the 30-minute recording. Timing on the transcript was established by correlating two air traffic control-recorded transmission times to corresponding CVR-recorded transmission times. The recording began when the airplane was on the ground at ECP at 2151. The flight departed ECP at about 2154.

A transcript of the CVR can be found in the public docket for this investigation. The transcript began at 2214:45 and continued until the end of the recording at 2222:32. Generally during the recording, the background sound of the engines oscillated, similar to the airplane operating in some degree of turbulence. Sounds of precipitation could not be uniquely identified in the recording.

WRECKAGE AND IMPACT INFORMATION

The accident site was located about 3.4 miles east-southeast of Camilla, Georgia, and wreckage was scattered over a large area that included a cotton field and dense forest. The debris field was about 2,640 ft long and 1,500 ft wide and oriented on a heading of 049° true. The wings outboard of the engine nacelles, wing extensions, empennage, ailerons, and cargo door separated from the airplane during the accident sequence and were located along the debris path leading to the main wreckage. The first components located along the debris field were the outboard sections of both wings, which exhibited damage and paint transfer consistent with contact with the fuselage. Additional components located along the debris path included the empennage and the mid-span portions of both wings. The fuselage came to rest at the end of the debris path beside a residence. The fuselage, cockpit, cabin section, inboard wings, and both engines were damaged by the postcrash fire.

The wreckage was recovered and examined at Atlanta Air Salvage's facility in Griffin, Georgia. The examination revealed that the left outboard wing separated from the airplane just outboard of the nacelle, and the left wing tip extension separated from the outboard wing. The leading edge was separated into several pieces. A distinct diagonal crease ran from the leading edge to the trailing edge of the wing, with the portion of wing outboard of the crease deformed upward. The wing structure exhibited substantial twisting and crushing damage in a fore-aft direction. The lower left wing skin was separated into several pieces. The left wing forward upper spar cap remined attached to the outboard wing and the inboard portion was deformed up and aft. The lower forward spar cap was separated from the wing and exhibited S-bending. The left wing rear spar upper spar cap was fractured and the inboard portion was not identified. The lower rear spar cap was fractured. The portion of lower rear spar cap was separated and deformed up and aft. The rear spar cap inboard was not identified. The left aileron was separated from the wing and recovered in three pieces. The left aileron trim tab remained attached to the inboard aileron piece. The left aileron bellcrank and control rods remained att

NTSB Probable Cause

The pilot's decision to initiate and continue the flight into known adverse weather conditions, which resulted spatial disorientation, a loss of airplane control, and a subsequent in-flight breakup.