Accident Overview
On December 7, 2016, at approximately 1043 Alaska standard time, a tailwheel-equipped Bellanca Citabria 7GCBC airplane (registration N88452) sustained substantial damage when it impacted terrain about 17 miles southeast of Fairbanks, Alaska. The airline transport pilot, who was the sole occupant, was fatally injured. The aircraft was operating under Title 14 Code of Federal Regulations Part 91 as a visual flight rules (VFR) personal flight. A VFR flight plan had been filed and activated. The flight departed Chena Marina Airport (AK28) at 1026.
Pilot and Flight Details
The 74-year-old pilot held an airline transport pilot certificate with multi-engine land rating and commercial privileges for single-engine land and sea. He reported 3,171 total flight hours, including 2,736 hours in single-engine airplanes and 206 hours in a Citabria 7GCBC. According to family members, he was well rested and in good health that morning. The flight was intended to test the aircraft's performance following the installation of Micro Aerodynamics vortex generators on the wings and horizontal stabilizer. The mechanic noted that the engine ran rough after the first start, so the aircraft was warmed in the hangar before a successful second start.
Archived radio communications show the pilot obtained current weather and altimeter setting from Fairbanks International Airport (FAI) tower before departure. He activated his VFR flight plan after takeoff. The last transmission, at 1033, inquired whether restricted airspace R-2211 was active; the tower replied it was cold.
A Garmin GPSMAP 296 recovered from the wreckage provided detailed flight data. After takeoff, the aircraft climbed southeast, then conducted multiple turns at low altitude, followed by slow flight maneuvers consistent with stall practice. The aircraft slowed to 46 knots and 40 knots during these maneuvers. At 1040:52, it turned southeast, descended, and decelerated before entering a rapid descent at about 2,000 feet per minute. The last valid GPS data indicated an altitude of 587 feet (75 feet above ground), groundspeed 35 knots, and track 144°. About 2.5 hours later, two US Army CH-47F helicopter crews located the wreckage after hearing an emergency locator transmitter signal.
Aircraft Information
The two-seat, high-wing Bellanca Citabria 7GCBC was manufactured in 1974, powered by a 150-horsepower Lycoming O-320-A2D engine with a fixed-pitch, two-bladed McCauley propeller. It had been altered with metal wing spars and was equipped with Landis L-2000A straight skis and Micro Aerodynamics vortex generators per FAA supplemental type certificates. The optional stall warning horn was not installed. The last annual inspection occurred April 4, 2016; the throttle cable was replaced the week before the accident due to stiffness, and the alternator was replaced the day before due to electrical issues. The transponder had been removed for maintenance.
Weight and balance calculations, based on estimated fuel and pilot weight, indicated a takeoff weight of 1,705 pounds, exceeding the maximum allowable gross weight of 1,650 pounds. At the time of the accident, with about 24 gallons of fuel, the calculated weight was 1,687 pounds; the center of gravity was within limits.
Wreckage Examination
The wreckage was located on Fort Wainwright in an open, snow-covered area with black spruce trees. The aircraft came to rest intact, resting on the ground in a right 30° bank and slightly nose-down attitude. Initial impact was marked by three freshly fractured spruce tree tops about 350 feet northwest of the wreckage; the tallest was 55 feet. Two parallel ski marks in the snow indicated ground impact on a bearing of 140°.
The right wing sustained fore-aft crush damage and leading-edge compression; tree bark and spruce needles were present. The left wing separated from the airframe and folded inverted over the fuselage. The empennage remained attached, with crush damage to the right horizontal stabilizer. Control continuity was established for elevator, rudder, and ailerons. The flap handle was in the full-up notch (flaps fully down). The throttle and propeller controls were full forward; the mixture was slightly out; carburetor heat lever was slightly aft of full forward. The altimeter indicated 620 feet with a Kollsman setting of 30.68; the vertical speed indicator showed 175 fpm; the accelerometer recorded -2, 2, and a maximum load factor of 12 Gs.
The pilot's lap belt was latched and attached to the seat frame, which was partially detached. The shoulder harness was disconnected from the lap belt; the inertial reel remained attached to the cabin overhead tubing, which had torn away. The pilot seat had been altered with thin metal brackets to allow aft installation.
Engine examination revealed no anomalies or malfunctions that would have precluded normal operation. The propeller remained attached; one blade fractured near mid-section, the other exhibited torsional twist. Magnetic examination of the left wing strut and throttle cable mount fractures showed overstress separations with no preexisting defects.
Meteorological Conditions
At 1053, the recorded weather at Fairbanks International Airport (16 miles north, elevation 432 ft) was wind 010° at 5 knots, visibility 10 miles, sky clear below 12,000 ft, temperature -33°C, dew point -36°C, altimeter 30.63 inches of mercury. Sunrise occurred at 1037; the sun elevation was 0.1° above the horizon at accident time. The NTSB investigator noted sun glare while flying to the site on December 9.
Additional Information
No military aircraft flights were operating near the accident site per US Army Alaska command. Radar coverage was limited due to terrain interference; no primary or mode C targets were recorded.
The Bellanca Pilot Operation Manual lists power-off stall speeds: flaps up at 43 knots CAS, flaps down at 39 knots CAS. Vortex generator manufacturer claimed an 8% reduction in stall speed, but no guidance was provided on flight test procedures to determine adverse effects. Flight test data submitted for STC approval noted that a definite left-wing drop before VG installation was not present after installation.