History of Flight
On June 16, 2021, at about 1345 mountain daylight time, a Lancair Evolution, registration N704AK, was destroyed in an accident near Parker, Colorado. The private pilot and copilot sustained fatal injuries. The airplane was operating under Title 14 Code of Federal Regulations Part 91 as a personal flight.
According to air traffic control (ATC) information, the airplane was established on the RNAV (GPS) runway 35R approach to Centennial Airport (APA) about 7 miles south of the airport in visual meteorological conditions. The copilot contacted the tower controller, who issued wind conditions and cleared the airplane to land on runway 35R. When the airplane was about 3 miles from the end of the runway, it began a left turn and descended. The descending left turn continued to the accident site. When the airplane was about 2.6 miles from the runway, the controller asked if the pilot was executing a 360° turn; the copilot responded that the autopilot had failed. During this turn, the airplane descended below the minimum altitude for that segment of the instrument approach.
Several construction workers near the accident site observed the airplane flying low and saw its left wing impact powerlines. They reported that the airplane “exploded” after hitting the powerlines. The airplane came to rest on a hillside, and a postimpact fire consumed most of the composite airframe.
Personnel Information
The pilot and copilot were a married couple. According to their daughter, the mother was the pilot occupying the left seat, and the father was the copilot in the right seat, assisting with flying and radio calls.
The pilot owned a company that provided training for Lancair Evolution airplanes. The company’s president and chief pilot, who had signed off the pilot to fly the accident airplane, described her as a great pilot with excellent stick-and-rudder skills, decision-making skills, and instrument flight rules (IFR) skills. He stated she was one of the best pilots he had trained. Company training records for the pilot and copilot were not available during the investigation. The chief pilot noted that both had flown into APA multiple times and were familiar with the airport, instrument approaches, and operating area.
Aircraft Information
The Lancair Evolution is a high-performance airplane equipped with a primary flight display, a multifunction display (MFD) with instrument-certified GPS and traffic/terrain graphics, and a fully integrated autopilot. The builder-developed checklist for the accident airplane was not available.
A review of maintenance records showed that paint work was performed on the airframe in June 2019, during which all flight controls were removed. A follow-up entry noted that flight controls were balanced and installed with new hardware. The most recent condition inspection was completed in October 2020.
The Lancair Evolution Pilot’s Operating Handbook (POH) and Airplane Flight Manual (AFM) describe the electrically operated wing flaps. The flap control switch on the instrument panel has three positions: fully up retracts flaps to 0°, middle extends flaps to the takeoff/approach position of 24°, and full down extends flaps to the landing position of 48°. Flap position is indicated on the MFD. The preflight checklist requires lowering the flaps from the cockpit and checking left and right flap attachment points and movement.
Wreckage and Impact Information
The airplane struck two east/west-oriented transmission static lines strung between transmission towers. The towers had flashing lights on top, and the powerlines were marked with multi-colored marker balls. The accident site elevation was 6,270 ft msl. The airplane came to rest about 200 ft north of the powerlines on a 50° incline, 3.4 miles from the approach end of runway 35R on a heading of 336°. The airplane was destroyed by postimpact fire.
Both flaps sustained fire and impact damage. The left flap control rod end and its attachment bolt were missing, but threads for the bolt were intact in the attachment bracket. The area around the threaded hole showed rubbing consistent with off-axis contact with the outboard end of the flap control rod attachment bolt. Corresponding off-axis contact deformation was found on the edge of the control rod attachment bolt through-hole on the inboard side of the bracket. The aft attachment bolts for the left flap control bracket were secured with safety wire.
A piece of the right flap control rod remained attached to the bracket with an intact control rod attachment bolt. The aft attachment bolts for the right bracket were also safety-wired. The head of the right flap control rod attachment bolt had a hole for safety wire, but no safety wire was attached to it.
The Lancair Evolution Build Manual instructs builders and maintenance personnel to safety-wire the flap control rod attachment bolt to prevent loss of the bolt and corresponding flap control.
No preimpact mechanical malfunctions or failures were found with the engine or propeller.
In October 2021, Evolution Aircraft Company issued Service Advisory SA016-0036 regarding inspection of Evolution airplane attach points. The advisory includes an illustration from the Build Manual stating “safety wire bolt through bearing” with arrows pointing to both flap control attachment brackets, and a photograph showing a proper flap control rod attachment with safety wire securing the control rod attachment bolt to the upper aft attachment bolt. The advisory reminds owners to include critical safety-of-flight items in preflight inspections.
Tests and Research
The Lancair Owner and Builders Organization (LOBO) conducted a postaccident evaluation using X-Plane flight simulator to assess an asymmetric flap deployment scenario. A left flap failure was induced, causing the left flap to remain retracted. At 90 knots with the left flap at zero and the right flap at takeoff setting, full right aileron and nearly 20% right rudder were needed to keep the wings level. With the right flap fully extended, no control input could maintain wings level, and the roll was described as “extremely quick.”
Additional Information
The Lancair Evolution POH/AFM and the LOBO training manual both provide guidance on flap system malfunction: maintain airspeed between 140 and 160 KIAS, check the flap circuit breaker, and verify flap indicator agrees with position. If asymmetry or rolling moment occurs, retract the flaps.
The FAA Pilot’s Handbook of Aeronautical Knowledge notes that advanced avionics can both increase and decrease pilot awareness. Proper automation management requires understanding how the autopilot interacts with other systems. While electronic displays reduce workload, they can capture attention for extended periods. Pilots should plan when to program approaches and consider their capabilities regarding last-minute changes.