History of Flight
On November 17, 2010, about 2050 eastern standard time, a Cessna M337B, registration N1309, impacted terrain after the right wing separated in flight near Avon Park, Florida. The airplane was registered to a private individual and the public use flight was operated by Patriot Technologies LLC under a contract with the Department of Defense. The commercial pilot and two pilot-rated crewmembers were killed. Night instrument meteorological conditions were present, and no flight plan was filed. The flight originated at MacDill Air Force Base Auxiliary Field (AGR) in Avon Park about 1932.
The flight, using call sign "Jedi 21," was providing aerial support to an Air Force Special Operations Command training exercise. Tower instructed Jedi 21 to report a two-mile final for runway 5. When the flight did not report, a search was initiated. The wreckage was located about 0118 on November 18.
Several Department of Defense personnel were on the Avon Park Air Force Range at the time, including range and airspace controllers, a weather forecaster, and other flight crews. A Restricted Operating Zone controller reported that Jedi 21 checked in and worked on his frequency for about an hour until reporting a "bent sensor" (a term for a technical anomaly). The controller continued with Jedi 21 for about 30 more minutes before checking off.
Another controller reported that about 2040, Jedi 21 stated they were returning to base. The controller requested the reason but received no response. About 2055, tower inquired about Jedi 21; the controller believed the flight had landed. Around the same time, weather conditions became severe at AGR with heavy rain and limited visibility.
A communications link staff member heard the return-to-base call and no response. About 2045, Jedi 21 called "inbound to Avon Aux Field" and then reported 4 miles from AGR, the last radio call. Weather worsened with heavy rain about 2055.
A weather forecaster reported that conditions were initially clear, with mid-level clouds increasing. Weak radar returns to the south were expected to dissipate. His assessment was no significant weather event other than a brief heavy shower, which occurred after communication was lost. Between 1930 and 2000, showers to the southwest were tracking northeast. He recommended a recall of VFR aircraft at 2035 due to worsening conditions. From 2050 to 2055, a brief heavy shower reduced visibility to 1–2 miles.
An H60 helicopter pilot reported weather was worse than briefed, with visibilities 1–2 miles. At 2015, they experienced zero ceiling and visibility at AGR but landed safely.
Another Patriot Technologies aircraft was airborne. The pilot recalled no mention of precipitation in the briefing. Weather deteriorated rapidly, and he aborted the mission, eventually landing at Sebring Airport. He did not receive additional weather information or a recall.
A witness 1–2 miles north of the accident site heard the airplane at full throttle and then a thud. He called 911. No explosion. It started raining hard immediately after. A second witness about 3/4 mile from the site heard the airplane sound normal then like a dive bomber. The engine rpm increased until the crash. He called 911. A terrible storm hit a few minutes later with heavy rain but no thunder.
Radar data showed a primary target on a south-southeasterly heading, terminating about 2050 at a location near the accident site. No altitude or airspeed data were captured.
Personnel Information
The pilot in command, seated in the left cockpit, held commercial pilot certificates for single-engine and multi-engine land, and an instrument rating. He was also a flight instructor. He reported 6,200 civilian flight hours on his medical certificate application dated December 29, 2009. According to an operator form dated October 5, 2010, he reported 10 hours in the Cessna 337/O-2 and about 3,500 military flight hours.
A commercial pilot was seated in the right cockpit. Another commercial pilot was in the aft right seat. Both were assigned duties operating tactical and communications equipment. The duties of the right-seat crewmember did not include flying.
Aircraft Information
The airplane was a Cessna M337B, serial number 337-M0015, originally built as an O-2A for the U.S. Air Force. It was powered by two Continental IO-360-D engines, each rated at 210 horsepower. No weather radar was installed.
Maintenance records showed an annual inspection on October 14, 2010, at 5,566.9 total hours. The forward engine had 1,260.3 hours since overhaul; the rear engine had 1,111.8 hours. On October 11, 2010, an eddy current inspection of bolt holes in the front wing spar lower cap was performed with no discrepancies found.
Meteorological Information
A stationary front extended east-to-west over southern Florida. Radar and satellite imagery showed an area of cumulus congestus clouds. Doppler radar at 2052 depicted echoes up to 55 dBZ near the accident site. No lightning was observed. AGR had no weather reporting. Other stations reported VFR conditions. The mass weather briefing did not include any indication of hazardous weather.
Wreckage and Impact Information
The main wreckage was found adjacent to a retention pond on a farm pasture. An initial impact crater (7 ft x 9 ft x 3 ft) contained the cockpit instrument panel, forward engine, and propeller parts. A ground scar matching the left wing leading edge was adjacent. The wreckage path was oriented about 130 degrees. Tail booms, stabilizers, and a section of the left wing were in the pond. The aft engine was inverted on the pond edge.
Two sections of the right wing were found northwest of the main crater: an outboard section about 800 feet away and another section with a flap about 330 feet away. Examination revealed no preexisting mechanical anomalies. All fracture surfaces showed overload failure. No fatigue or corrosion was found.
Medical and Pathological Information
Postmortem examinations listed cause of death as blunt force trauma for all three occupants. Toxicology tests for the pilot and front right seat occupant were negative for drugs and ethanol. The rear seat occupant tested positive for ethanol in muscle, lung, liver, and kidney. Carbon monoxide and cyanide tests were not performed.
Tests and Research
The airplane was equipped with an AeroComputers UC5100 tactical mission management system. Memory cards were examined; the accident flight data covered the flight up to about 2045 (about 8 minutes before impact). The system is not essential for flight and is normally powered down after a mission.