N5939DPiper PA-22-150 · 1956

On December 27, 2020, about 1300 eastern standard time, a Piper PA-22-150, N5939D, was

substantially damaged when it was involved in an accident near Cleveland, Georgia. The pilot and passenger received minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

According to the pilot, he completed a preflight inspection and noted that the airplane contained 16 gallons of fuel. He started the engine and idled for 4 minutes to warm it up, then taxied the airplane to the departure end of the runway, performed an engine run-up, and did not note any anomalies. He stated that the total time idling on the ground was about 10 to 12 minutes. The pilot then taxied onto the runway, applied full engine power, and initiated the takeoff. During the initial climb, the engine lost power and the airplane began to settle. The pilot applied carburetor heat and switched the fuel selector from the right tank to the left tank; the engine surged, but then lost total power again. He turned off the carburetor heat and pitched the airplane down to maintain airspeed. The airplane continued to settle until it impacted treetops, resulting in substantial damage to the wings and fuselage.

The engine was examined on the airframe at a salvage facility by a Federal Aviation Administration inspector. A test run revealed no anomalies. Examination of the carburetor also revealed no anomalies.

At 1735, the weather reported at Toccoa Airport – RG Letourneau Field (TOC), about 21 miles east of the accident site, included a temperature of 11°C and a dew point -3°C. The calculated relative humidity at this temperature and dewpoint was 40%. Review of the carburetor icing probability chart contained within Federal Aviation Administration Special Airworthiness Information Bulletin CE-09-35 revealed the atmospheric conditions at the time of the accident were "conducive to icing at glide and cruise power."

FAA Advisory Circular (AC) 20-113, "To prevent accidents due to induction system icing, the pilot should regularly use [carburetor] heat under conditions known to be conducive to atmospheric icing and be alert at all times for indications of icing in the fuel system." The AC recommended that when operating in conditions where the relative humidity is greater than 50%, "…apply carburetor heat briefly immediately before takeoff, particularly with float type carburetors, to remove any ice which may have been accumulated during taxi and runup." It also stated, "Remain alert for indications of induction system icing during takeoff and climb-out, especially when the relative humidity is above 50%, or when visible moisture is present in the atmosphere."