Accident Sequence
The flight departed under visual flight rules (VFR). Near the destination airport, air traffic control advised the pilot to hold VFR over the "plaza" and perform left 360-degree orbits. Radar data showed the pilot executed one 360-degree left turn with varying bank angles, initially at 1,300 feet, climbing to near 1,500 feet, then descending to approximately 800 feet. Between 1502:10 and 1502:27, calibrated airspeed decreased from 160 to 100 knots. At 1502:27, the bank angle was 48 degrees and the angle of attack was 26 degrees. Between 1502:30 and 1502:35, the heading changed, indicating a bank to the right. The last plotted altitude was 200 feet at 1502:35.
Witness Observations
Several witnesses reported light rain at the time, with no lightning or thunder. One witness, located where the airplane came to rest, saw the airplane emerge from the base of clouds in a 45-degree left wing low and 20-degree nose low attitude, then roll to wings level. He heard the engines "cutting in and out." Another witness, about 1/4 mile north, saw the airplane flying eastbound beneath clouds in a right wing and nose low attitude, also hearing the engines "cutting in and out." A pilot-rated witness, about 1,000 feet from the accident site, estimated the ceiling at 300 feet with light drizzle. He observed the airplane in a 45-degree right bank with slight nose low attitude until losing sight at 250 feet.
Impact and Damage
The airplane impacted trees and a concrete wall while in a nose and right wing low attitude. It then traveled through automobile hoists/lifts covered by corrugated metal, coming to rest adjacent to a building. Impact and post-crash fire destroyed the airplane, a building, and several parked vehicles. Parallel slash marks 25 and 21 inches apart were found on corrugated metal panels. According to the airplane manufacturer, the 25-inch spacing corresponded to an airspeed of 123 knots. The power-off stall speed at the calculated weight with flaps retracted and 48-degree angle of bank was 122 knots.
Examination Findings
Examination revealed the flaps were symmetrically retracted and landing gears were retracted. No evidence of preimpact failure or malfunction was found in the flight controls. Engines and propellers showed no preimpact failure or malfunction; impact and fire damage precluded testing of some engine accessories.
Weather Information
A National Weather Service (NWS) study indicated VIP level 1 to 2 echoes (light to moderate intensity) at the area and altitude of operation. The terminal aerodrome forecast (TAF) for the destination airport indicated temporary conditions between 1400 and 1800 of visibility 5 miles with moderate rain showers, scattered clouds at 1,500 feet, and a broken ceiling at 3,000 feet.