Sling 2 Forced Landing in South Africa (ZU-FVW)

Incident Overview and Flight Details On 12 August 2014, a Sling 2 aircraft, registration ZU-FVW, was conducting a private flight from Port Elizabeth (FAPE) International Aerodrome to Tedderfield (FATA) in Gauteng, South Africa. The aircraft was operated by Madiba Bay School of Flight and was certified for pilot training operations under Part 141 of the South African Civil Aviation Regulations. The flight was piloted by a 28-year-old Angolan national holding a valid South African Civil Aviation Authority (SA CAA) private pilot licence, accompanied by one passenger. The pilot had a total of 168.3 flying hours, with 124.3 hours on the Sling 2 type. The flight was intended to build up the pilot's flying hours. The aircraft was a single-engine, low-wing monoplane powered by a 100-horsepower Rotax engine and equipped with a glass cockpit, electronic flight instrument system (EFIS), and a Magnum 601 ballistic parachute. The aircraft's total airframe hours at the time of the accident were 1,682.1. ## Sequence of Events and Emergency Response The flight departed Port Elizabeth under visual meteorological conditions (VMC) with CAVOK weather reported. After an uneventful takeoff from runway 28, the aircraft climbed to flight level 095 at 90 knots indicated airspeed. Approximately 1.5 hours into the flight, smoke began emanating from the cockpit instrument panel, accompanied by an electrical burning odour. The pilot alerted Cape Town control tower via radio, but the radio became inoperative during the communication. All electrical equipment, including the transponder and EFIS screen, subsequently failed. The pilot attempted to use the backup EFIS screen without success. As the smoke intensified, obscuring the horizon, the pilot descended to flight level 075. During the descent, the engine stopped. The pilot attempted a restart using the engine control unit (ECU) backup switch but was unsuccessful. The pilot then identified an open space on Thorn Groove farm in the Cacadu district municipality and executed a forced landing. During the landing, the nose wheel collapsed, and the propeller struck the ground. The aircraft was substantially damaged, with the landing gear, wings, propeller, and lower cowling affected. No fire occurred, and both occupants were uninjured but shaken. The pilot vacated the aircraft and contacted the operator via cell phone. The FACT control tower reported unsuccessful attempts to establish radio contact. The aeronautical rescue coordination centre (ARCC) in Johannesburg was informed that the aircraft had disappeared from surveillance radar. The South African Police Service (SAPS) was notified, and the aircraft was located by a Squirrel helicopter during an aerial search. A rescue team landed at the site without incident. ## Investigation Findings and Probable Cause The investigation determined that the in-flight engine stoppage was the result of a latent defective voltage regulator installed on the aircraft, which caused an electrical system failure. The probable cause of the accident was an unsuccessful forced landing following the in-flight engine stoppage. The contributing factor was the electrical system failure. The pilot had performed a thorough pre-flight inspection and reviewed the aircraft's technical documentation before departure, with no abnormalities noted. The aircraft's maintenance organization held a valid approval certificate, and all relevant documentation was in order. The accident occurred at GPS coordinates S 32° 50.45.0′ E 025° 48.25.0′ at an elevation of approximately 1,782 feet above mean sea level.