Accident Overview
On July 17, 2010, at 1527 eastern daylight time, an experimental S.C. Aerostar S.A. Yakovlev 52, registration N52MY, collided with terrain after an in-flight loss of control following takeoff from runway 29 at Portland International Jetport (PWM) in Portland, Maine. The flight was operating under 14 CFR Part 91 with no flight plan filed. Visual meteorological conditions prevailed. The private pilot and a certificated flight instructor (CFI) were fatally injured, and the airplane sustained substantial damage.
History of Flight
Witnesses reported that after takeoff, the airplane's wings began rocking back and forth as it climbed. It then initiated a left turn back toward the airport. Several witnesses observed the airplane bank left and then nose straight down. Those who did not see the impact reported a large cloud of dust. Surveillance video confirmed a descent into terrain.
According to the air traffic controller at PWM, the airplane had completed two successful touch-and-go landings and a third full-stop landing. The pilot then back-taxied for an engine run-up. Following the run-up, the pilot requested takeoff and stated he needed to perform a systems check, intending to climb to 3,000 feet and remain over the airport. During takeoff, wings began rocking; the controller asked if the pilot needed to return. The pilot replied yes and began a slow left turn. When asked if there were problems, the pilot responded, "no, but it's getting awfully hot in here." The controller then saw the airplane nose down into the ground.
Pilots
The private pilot, aged 42, held a private pilot certificate for single-engine land, issued November 24, 1987, and a second-class medical certificate dated April 9, 2010, with a requirement to wear corrective lenses. His logbook indicated his last flight was on September 5, 2008, for 1.9 hours in the accident airplane. Total flight time was 416.8 hours, with approximately 105 hours in the accident airplane. His last flight review was completed June 23, 2008.
The CFI, aged 66, held an airline transport pilot certificate with ratings for single-engine land, multiengine land, rotorcraft helicopter, and instrument airplane and rotorcraft. He also held commercial and flight instructor certificates. His most recent second-class medical certificate was issued September 1, 2000, with a corrective lenses restriction.
Aircraft
The two-seat, low-wing, retractable-gear, single-engine airplane (serial number 856211) was manufactured in Romania in 1985. It was powered by a nine-cylinder Vendeneyev M14P 360-horsepower engine and equipped with a V530TA-D35 two-bladed wooden propeller. It received an experimental exhibition airworthiness certificate on September 12, 2001. The most recent annual condition inspection was performed July 2, 2010, at an airframe total time of 1,038.2 hours and Hobbs time of 105.3. The engine had accumulated 139.3 hours since major overhaul. Hobbs time at accident was 106.1 hours.
Meteorological Information
Recorded weather at PWM at 1451: wind 250° at 11 knots gusting to 17 knots, visibility 10 statute miles, scattered clouds at 6,000 feet, temperature 32°C, dew point 18°C, altimeter 29.73 inHg.
Wreckage and Impact Examination
The airplane impacted a manhole cover on the south side of Maine Mall Road, then traveled about 70 feet on a 011° heading to the north side of the road, coming to rest upright on a heading of 200°, approximately 1/4 mile southwest of runway 11 threshold. The fuel sump was compromised; about 20 gallons of fuel spilled. A small postcrash fire in the engine compartment was extinguished by a local business employee.
Examination found 6 feet of the outboard right wing separated; the wing spar partially separated at its attaching point; the right wing forward attach bolt sheared. The empennage aft of the rear cockpit was displaced left. Control continuity was established to all flight controls. Landing gear and flaps were retracted. The engine and firewall were displaced left. Pilot's canopy was fully open; rear canopy partially open. Flap and landing gear handles were neutral; throttle at idle. Seven of eight circuit breakers were off; the eighth (powering landing gear, fuel quantity, oil pressure, etc.) was on.
Engine examination: one propeller blade separated at hub, the other at mid-span, consistent with low rotational energy. Cylinders 6, 7, 8 had impact damage; others intact. Oil screen clear. Both magnetos produced spark. Generator impact-damaged but rotated freely. Engine-driven oil pump rotated freely. Cylinders 6, 7, 8 removed due to impact damage. Accessory section removed; all bolts stripped out of supercharger case. Supercharger main drive gear bound, preventing engine rotation; supercharger case fractured in three places. After drive gear removal, engine rotated freely.
Thumb compression check: cylinders 1, 4, 6, 9 had no compression. All cylinders removed; foreign material under exhaust valves prevented closure. Spark plugs normal.
Fuel pump examination: pump operated momentarily under electric drill but would not pump water; drill could not duplicate 3,000 rpm. Bypass valve allowed air passage. Internal corrosion noted on bypass valve and fuel inlet line. Fuel lines replaced during recent inspection with U.S. hose fitted to original fittings. Fuel pump, lines, filters, and transducer sent to NTSB Materials Lab. Lab tests: pump could pump water when primed and rotated counterclockwise; no preimpact failure. Both fuel filters had no contamination. One fuel line had fractured end fittings with overstress features; no preexisting crack. Four of six lines inspected with borescope; no blockage. Two smaller lines patency checked with copper wire and cotton ball; no debris. Fuel flow transducer had no preexisting cracking.
Medical and Pathological Information
Autopsies were performed on both pilots by the Maine Office of Chief Medical Examiner. Toxicological testing was conducted by the FAA Bioaeronautical Science Research Laboratory.
Additional Information
A handheld GPS receiver recovered from the wreckage was examined; no non-volatile memory was stored. The aircraft's original seller noted a past problem with metric-sized fuel hoses; U.S. hoses could cause partial obstruction. However, no tear debris was found in the fuel system during examination.