Accident Details
Probable Cause and Findings
The pilot's failure to properly secure oil and fuel line fittings during maintenance, which resulted in an inflight engine fire, and his subsequent loss of control while maneuvering for landing. Contributing to the accident was the pilot's diverted attention due to the inflight fire.
Aircraft Information
Registered Owner (Historical)
Analysis
HISTORY OF FLIGHTOn February 28, 2017, about 1302 eastern standard time, an experimental, amateur-built Sonex, N315AL, was substantially damaged when it collided with a building in Methuen, Massachusetts, during final approach for landing at Lawrence Municipal Airport (LWM), Lawrence, Massachusetts. The sport pilot was fatally injured. The airplane was owned by the pilot who was operating it under the provisions of Title 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed near the accident site at the time of the accident, and no flight plan was filed for the local personal flight.
An acquaintance of the pilot reported that the pilot had experienced fuel leaks in the cockpit due to a cross-threaded connector. He stated that the pilot spent most of his time doing maintenance inside the cockpit. In an e-mail sent to his Experimental Aviation Association (EAA) chapter on February 25, the pilot reported that the last time he flew the airplane was on October 8, 2016. He had removed and reinstalled the fuel tank twice due to a cross-threaded outlet fitting that was causing a fuel leak at the fuel outlet connection near the fuel shutoff valve in the cockpit. He stated that the issue was fixed and that he would fly the following Tuesday (the day of the accident), during which he would remain in the airport traffic pattern and "do a bunch of touch-and-goes to make sure everything is working correctly."
On the day of the accident, the pilot purchased 12 gallons of fuel about 1245. The pilot then informed the tower controller that he would be remaining in the traffic pattern to practice takeoffs and landings. The controller issued a takeoff clearance and instructed the pilot to make a left closed traffic pattern and to report mid-field downwind. The pilot acknowledged and departed runway 14; he then reported mid-field at an altitude of 1,400 ft above ground level (agl). The pilot was subsequently cleared to land, but he never acknowledged the clearance.
The controller reported that, as the airplane turned onto the final leg of the traffic pattern about 500 ft agl, another airplane was "over the numbers" getting ready to land. He stated that, although spacing did not appear to be an issue, he observed the accident airplane make a shallow s-turn maneuver to the left, then back to the right before it suddenly nosed over in a right turn and disappeared out of view.
Several witnesses on the nearby highway saw the airplane approach from the north, then make a sudden dive before disappearing behind trees. One witness stated that the belly of the airplane was "engulfed in flames." He described the flames as "very bright red" and stated that the airplane looked like a "meteor." He stated that flames also appeared to be behind the propeller, which was turning, and "under where the pilot would sit." Additional witnesses called 911, reporting that they saw a plane go down, that it was "on fire," and that the airplane "burst into flame." PERSONNEL INFORMATIONAccording to Federal Aviation Administration (FAA) airman records, the pilot received his sport pilot certificate on May 21, 2014. Review of his logbook revealed 128.5 total hours of flight experience and 28 hours in the accident airplane make model as of his last logged flight about four months before the accident. The pilot did not hold an FAA medical certificate, nor was he required to as a sport pilot. AIRCRAFT INFORMATIONThe pilot/owner purchased the airplane in January 2015 from the manufacturer in kit form. The pilot/owner completed the build and it was issued a special airworthiness certificate for experimental airplane on May 4, 2016. It was a two-seat, single-engine, low-wing, tailwheel-equipped airplane that was equipped with a Jabiru 3300L six cylinder, 120-horsepower reciprocating engine. Airframe maintenance records indicated that the airplane had accumulated 28.4 hours total time as of the last recorded entry on October 8, 2016; on this day, the pilot flew 1.4 hours. The engine logbook had one entry dated May 1, 2016 that reported, "ground run no leaks." No additional engine maintenance was documented. METEOROLOGICAL INFORMATIONThe 1254 automated weather observation at LWM included variable wind at 4 knots, 10 miles visibility, scattered clouds at 9,000 ft, temperature 13°C, dew point -2°C, and an altimeter setting of 30.35 inches of mercury. AIRPORT INFORMATIONThe pilot/owner purchased the airplane in January 2015 from the manufacturer in kit form. The pilot/owner completed the build and it was issued a special airworthiness certificate for experimental airplane on May 4, 2016. It was a two-seat, single-engine, low-wing, tailwheel-equipped airplane that was equipped with a Jabiru 3300L six cylinder, 120-horsepower reciprocating engine. Airframe maintenance records indicated that the airplane had accumulated 28.4 hours total time as of the last recorded entry on October 8, 2016; on this day, the pilot flew 1.4 hours. The engine logbook had one entry dated May 1, 2016 that reported, "ground run no leaks." No additional engine maintenance was documented. WRECKAGE AND IMPACT INFORMATIONAll components of the airplane were accounted for at the accident site and there was evidence of both pre- and postimpact fire. The airplane struck the roof of a three-story condominium building located about 1,800 ft from the approach end of runway 14. The airplane was found in the attic and upper bedrooms in a nose-low attitude on a heading about 208°. The empennage partially protruded from the roof. Both wings remained attached to the fuselage at their respective wing roots and were bent aft about 45°. The bedroom where the airplane came to rest caught fire, but was quickly extinguished by the building's fire suppression system. Fire damage was limited to the rooms in the immediate vicinity of the airplane.
The engine separated from the firewall and came to rest upright against a wall about 5 ft forward of the fuselage. The engine exhibited fire damage on the left side. The two-blade fixed P-Tip propeller blades separated about 12 inches from the propeller hub. The 17-gallon polymer fuel tank remained intact and secured behind the firewall and directly forward of the instrument panel. It contained about 7 gallons of 100 low lead aviation fuel. Fuel lines leading from the fuel tank were severed during impact and were leaking when the fire department arrived on scene. The fuel shutoff valve, which was installed at the lower side of the tank above the pilot's feet, was separated and found loose in the wreckage and was heavily fire damaged; its preimpact position could not be determined. The aluminum plumbing between the valve and the gascolator was consumed by fire; however, the fittings remained intact. The firewall-mounted gascolator contained residual fuel that resembled 100 low lead aviation fuel. The filter contained no contaminants and was not damaged.
The throttle body separated from the engine but remained attached by the control cable and was slightly damaged by impact forces. It displayed exterior discoloration and sooting, but no evidence of internal damage. The fuel regulator component remained attached to the throttle body; however, the fuel line into the regulator from the fuel supply had no torque and was easily spun by hand where it was threaded into the regulator. The throttle body was opened and displayed some discoloration that appeared like soot inside the air intake. The fuel regulator showed some soot deposits. Both intake and outflow lines and their respective connection nuts and couplers were undamaged at the unit and did not show any signs of heat damage, but areas under and to the left of the unit showed evidence of fire.
The spark plugs were removed; the electrodes exhibited normal wear and color when compared to a Champion inspection chart. Examination of the magnetos revealed no anomalies. The engine crankshaft was turned manually; internal engine continuity was confirmed. Compression and suction were observed on all cylinders and valve action was correct.
Flight control continuity was confirmed by operating the push/pull rods to their respective locations on each flight control surface. All connections remained intact. The aileron connections were traced visually to the dual stick flight controls but could not be operated due to impact damage. Rudder control continuity was visually confirmed, but the controls could not be operated due to impact damage.
The engine sustained fire and heat damage, with the heaviest concentration of heat damage to the lower left side of the engine. Thermal damage propagated aft past the intake and exhaust manifolds through the rear of the engine. The oil filter was fused to the engine and could not be removed. The lower oil line that connected to the oil filter was not secured. The blue aluminum connection nut was loose. There was oil spray on the lower left side of the engine. The leading edge of the intact manifold expansion gaskets were heavily damaged by fire. All intake and exhaust manifolds on the left side of the engine showed evidence of external heat signatures. There was no evidence of heat damage to the right side of the engine. The engine cowl showed interior heat damage to the bottom side with the heaviest concentrations on the bottom left and aft.
Soot, discoloration, and heat signatures were on the bottom of the fuselage and on the leading edge of the radio antennae, which exhibited blistering. Soot was also on the inboard portion of the right wing, and a soot pattern was along the right side of the fuselage that originated from an area near the front of the airplane and extended out under the right wing toward the tail.
The instrument panel was impact- and heat-damaged. It contained an Xtreme-EFIS that can display primary flight display information, navigation information, and, optionally, engine information. The unit could not be separated from the instrument panel in ...
Data Source
Data provided by the National Transportation Safety Board (NTSB). For more information on this event, visit the NTSB Records Search website. NTSB# ERA17FA117