Accident Summary
On September 1, 2015, at approximately 1940 mountain daylight time, an Extra Flugzeugbau GMBH EA 300/L, registration N4BM, was destroyed when it struck terrain near the Jerome County Airport in Jerome, Idaho. The aircraft was registered to and operated by the pilot under Title 14 Code of Federal Regulations Part 91. The private pilot, the sole occupant, was seriously injured. Visual meteorological conditions existed, and no flight plan was filed. The local flight had departed JER about five minutes earlier.
Witness Account
A witness located at the airport reported that he saw the accident airplane take off and fly to the southeast. Another individual with him had requested that the pilot return for a flyby, so they went outside to watch. The witness observed the airplane southeast of the airport performing a loop. He estimated the airplane was around 1,500 feet above ground level near the top of the maneuver. As he walked away from the building to continue watching, the airplane descended out of his line of sight behind a building. He noted that it appeared to begin leveling out as it descended, and he thought it should have had enough altitude.
Pilot Report
The pilot reported no memory of the accident flight aside from getting into the airplane and waking up in the hospital five days later. He stated that his intention was to go on an easy flight to clear his mind after his wife passed away a couple of weeks earlier, and that he did not plan to perform aerobatics.
Physical Evidence
An FAA inspector examined the accident site, a corn field about half a mile southeast of the approach end of runway 27. All major structural components were found at the site. The wings, engine, and empennage were separated from the fuselage and located within the debris path, which local law enforcement reported to be about 375 feet long. The wreckage was recovered for detailed examination.
Aircraft Condition
The fuselage was largely intact, but the canopy glass had separated from its structure. The empennage separated roughly 30 inches aft of the rear seat. The throttle, mixture, and propeller control cables were pulled or stretched. The acro/center fuel tank was intact; applying air to the filler expelled residual fuel from the impact-damaged gascolator. Flight control continuity was established from the forward and aft control sticks to the left and right wing root and aft to the empennage separation point. Both control sticks remained interconnected. Left and right aileron control continuity was confirmed, with impact damage and overload fractures on the control torque tubes. Rudder cables were still attached to the rudder pedals and showed overload signatures at the fuselage separation area. The wings were mostly fragmented from impact damage. The empennage remained intact, including horizontal and vertical stabilizers, but the elevator and rudder surfaces were fragmented.
Engine Examination
The engine was separated from its mounts; both left and right magnetos were separated. The oil cooler sustained impact damage. Components including the accessory housing, rocker box covers, top spark plugs, and propeller assembly were removed. The engine was rotated partially by hand. Cylinder number two was filled with dirt and metallic debris (a portion of the intake elbow). Upon partial removal from the crankcase, manual rotation of the crankshaft achieved thumb compression and suction on cylinders 1, 3, 4, 5, and 6. Mechanical continuity of cylinder 2 was established, and a lighted borescope inspection revealed no internal physical or mechanical damage. No preexisting mechanical malfunction was found that would have prevented normal operation of the airframe or engine.
Probable Cause
The report does not specify a probable cause.