Flight Sequence
On July 28, 2016, about 1138 central daylight time, a Mooney M20J, registration N54PM, impacted terrain near Holmen, Wisconsin, while being vectored for an instrument approach to runway 18 at La Crosse Regional Airport (LSE) in La Crosse, Wisconsin. The commercial pilot, who was the sole occupant, sustained fatal injuries, and the airplane was destroyed. The flight was operated under Title 14 CFR Part 91 as a personal flight on an instrument flight rules flight plan. Day instrument meteorological conditions prevailed at the time. The flight originated from Willmar Municipal Airport-John L Rice Field (BDH) in Willmar, Minnesota, at 1024, and was destined for LSE.
A friend of the pilot reported that the pilot had planned the flight a few weeks earlier. The friend stated that he received a text message from the pilot at 1013 indicating readiness for takeoff, and the flight departed at 1024. According to Flightaware data, the flight was estimated to land at 1137.
Minneapolis Center provided radar vectors for the final approach course of the instrument landing system (ILS) runway 18 approach and then instructed the pilot to contact LSE Air Traffic Control Tower (ATCT). The pilot contacted LSE ATCT, reported being over Mindi (the locator outer marker for the ILS approach, 6.6 miles north of runway 18), and requested radar vectors for the localizer. LSE ATCT instructed the pilot to maintain 4,000 feet and contact Minneapolis Center for vectors. The pilot acknowledged, and no further radio transmissions were received.
A witness near the accident site reported hearing the airplane traveling at high speed around 1145 or 1150. The witness described the weather as "bad" with misting and cloud ceilings lower than 700 feet above ground level. The witness heard the engine running but could not localize the sound; the engine then stopped. Approximately 3 to 4 minutes later, the witness heard a "boom."
Pilot and Aircraft Details
The airplane was a Mooney M20J. The pilot's logbook indicated that his last instrument proficiency check, conducted in accordance with 14 CFR Part 61.57(d), was performed on September 7, 2013, in the accident airplane and included a 1.0-hour biennial flight review. The last filled page of the logbook contained flight entries from August 1 to May 31 with no year specified; the previous page had a final entry dated July 31, 2014. Additionally, an endorsement at the back of the logbook indicated a biennial flight review dated November 29, 2015.
Wreckage Examination
The accident site was located approximately 5.6 miles north/northeast of runway 18 at LSE, at an elevation of 805 feet msl. The wreckage path extended about 800 feet in length, oriented north/south through a grass and corn field. The fuselage, wings, empennage, control surfaces, engine, and propeller were all present along the wreckage path. At the northern edge, a 35-foot-long by 6- to 10-foot-wide area of corn stalks was cut at an approximately 45° angle sloping downward to the east. The engine, separated from the airframe, was located at the southern edge. The fuselage was upright about 80 feet south of the cut corn stalks. The left wing was found about 6 feet north of the fuselage, and the right wing about 45 feet east. No evidence of soot or fire was observed.
Examination confirmed flight control continuity from the wing and empennage surfaces to the cockpit controls, with separations consistent with overload. The wing flaps were in the 0° position. The propeller hub base remained attached to the engine crankshaft with all bolts in place, but the upper portion was broken off, with fracture surfaces exhibiting 45° granular features indicative of overstress. Both propeller blades were separated; one was buried near the northern wreckage edge, and the other about 35 feet from the corn stalks. Both blades showed leading edge damage and chordwise scratching consistent with rotation under power at impact.
The instrument panel was found about 37 feet south of the fuselage, with flight instruments separated and scattered along the path. The attitude indicator, vacuum-driven, was broken apart, exposing the gyro casing and gimbals; the gyro was missing. The gyro casing showed circumferential smearing and scoring. The engine-driven vacuum pump remained attached to the accessory section. Its drive teeth were intact, but the drive had separated from its opaque plastic coupling, with features consistent with torsional overstress. The coupling exhibited counterclockwise witness marks. The engine showed no mechanical anomalies that would have precluded operation.
Medical Information
An autopsy was not performed, and no toxicology samples were available for testing. During the pilot's most recent aviation medical examination, no concerns were reported by the pilot, and the aviation medical examiner identified no significant issues.