N31EW

HISTORY OF FLIGHTOn October 12, 2014, about 2240 central daylight time, a Beechcraft model 58 airplane, N31EW, was destroyed when it impacted trees and terrain in Palos Hills, Illinois. The private rated pilot and two passengers sustained fatal injuries. The airplane was registered to ARC Aviation LLC and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Marginal night visual meteorological conditions prevailed for the flight, which was not on a flight plan. The flight originated about 2235 from the Midway International Airport (MDW), Chicago, Illinois, and was en route to the Lawrence Municipal Airport, Lawrence, Kansas.

Radar track data showed that the airplane departed runway 22L at MDW and began climbing on runway heading (220 degrees). At 2238:01, the airplane had accelerated to a computed groundspeed of about 130 knots and climbed to an altitude of about 2,200 ft above mean sea level (msl). After reaching this altitude, when the airplane was about 3 nautical miles (nm) from MDW, the airplane then began accelerating and descending as it turned about 20 degrees to the left to a heading of 200 degrees, which was followed immediately by a turn to the right. By 2238:38, when the airplane was about 4.8 nm from MDW, the airplane had descended about 700 ft to an altitude of 1,500 ft msl. The airplane then began climbing. As the climb was initiated, a left turn was also initiated. The left turn continued while the radius of the turn decreased until the end of the radar data. During the final left turn, the airplane initially climbed about 400 ft, descended about 400 ft, and then climbed again about 1,300 ft before reaching a peak altitude of 2,800 ft msl at 2239:24. At this time the airplane was about 5.9 nm from MDW and about 0.1 nm from the accident site. The final radar data point was at 2239:29 at a recorded altitude of 2,400 ft. The final radar data point was located within 0.1 miles of the accident site, and about 6 nm southwest of MDW. The calculated rate of descent between the final two radar points exceeded 5,000 ft per minute. PERSONNEL INFORMATIONThe pilot, age 33, held a private pilot certificate with single-engine land, multiengine land, and instrument airplane ratings. He also held a third class airman medical certificate that was issued on January 31, 2012. The medical certificate listed no limitations.

Pilot logbook information recovered during the investigation revealed that the pilot received his multiengine rating on February 2, 2014. The records indicated that the pilot had accumulated 417.6 hours of total flight experience, including 114.4 hours of multiengine experience. Review of the records indicated that the multiengine experience included 11.5 hours of training, 7.9 hours of simulated instrument experience, 21.1 hours of actual instrument experience, and 25 hours of night flight experience. AIRCRAFT INFORMATIONThe accident airplane was a Beechcraft model 58 airplane, serial number TH-1939. It was a six-seat twin-engine monoplane with a retractable tricycle landing gear configuration. The airplane was powered by two 300 horsepower Continental IO-550-C six cylinder, reciprocating engines.

According to maintenance records, the most recent annual inspection was performed on May 12, 2014 and both engines had been overhauled during the annual inspection. At the time of the annual inspection the airframe had accumulated 1778.2 hours total time in service. The most recent maintenance action was performed on October 8, 2014, and the airplane had accumulated 1869.1 hours total time in service as of that date. METEOROLOGICAL INFORMATIONWeather conditions recorded by the MDW Automated Surface Observing System (ASOS), located about 6 miles northeast of the accident site, at 2153, were: wind from 160 degrees at 9 knots gusting to 17 knots, visibility 10 miles, overcast clouds at 1,700 ft above ground level (agl), temperature 16 degrees Celsius, dew point 12 degrees Celsius, and altimeter 29.89 inches of mercury.

At 2238, the MDW weather was: wind from 170 degrees at 9 knots, visibility 6 miles with mist, broken clouds at 1,000 ft agl, overcast clouds at 1,700 ft agl, temperature 15 degrees Celsius, dew point 13 degrees Celsius, and altimeter 29.89 inches of mercury.

The Aeronautical Information Manual defines marginal VFR weather conditions as ceilings from 1,000 to 3,000 ft agl and/or visibility 3 to 5 miles inclusive. AIRPORT INFORMATIONThe accident airplane was a Beechcraft model 58 airplane, serial number TH-1939. It was a six-seat twin-engine monoplane with a retractable tricycle landing gear configuration. The airplane was powered by two 300 horsepower Continental IO-550-C six cylinder, reciprocating engines.

According to maintenance records, the most recent annual inspection was performed on May 12, 2014 and both engines had been overhauled during the annual inspection. At the time of the annual inspection the airframe had accumulated 1778.2 hours total time in service. The most recent maintenance action was performed on October 8, 2014, and the airplane had accumulated 1869.1 hours total time in service as of that date. WRECKAGE AND IMPACT INFORMATIONThe airplane impacted trees and terrain in a residential area 6 nm southwest of MDW. Several tree branches exhibited clean cuts consistent with propeller impact and engine power production. Some of the cut branches were about 4 inches in diameter. The initial impact point was about 20 ft north of a house on the neighboring lot. The house and a sport utility vehicle parked in the driveway sustained damage from flying debris. The entire airplane was crushed and fragmented. All of the major airframe pieces were contained within the wreckage distribution path that extended to the southeast, across the street and into the front yards of the houses on the opposite side of the street. Most of the wreckage was located at the initial impact point with smaller pieces of debris scattered along the wreckage path. The proximity of the initial impact point with the surrounding trees was consistent with a near vertical impact. The entire fuselage was crushed and almost unrecognizable. The right engine propeller was about 1 ft below ground level and the engine crankshaft had fractured at the propeller hub. The engine was lying on the ground. The left engine was buried in the ground and the propeller was about 2 to 2-1/2 ft below ground level. The propeller was still attached to the engine. A cage for an air operated gyroscopic instrument was found among the wreckage debris. The circular bore of the cage contained rotational scoring that was consistent with operation at the time of impact. The wreckage was recovered and relocated to a storage facility for further examination.

A partial layout of the main airframe pieces was accomplished. All of the major airframe parts and flight controls were confirmed to be present during the layout. The main landing gear was retracted in the wheel wells. The vertical stabilizer remained attached to the aft fuselage. The rudder had separated with the mid and upper hinges and the rudder trim tab remained attached to the rudder. The rudder balance weight had separated. The right horizontal stabilizer remained attached to aft fuselage with the right elevator still attached. The right elevator trim tab remained attached and the right elevator balance weight remained partially attached. The right elevator torque arm remained attached with the control rod still attached. The left horizontal stabilizer remained partially attached to the aft fuselage. The outboard horizontal stabilizer had separated. The left elevator had separated and was torn into two main pieces. The left elevator trim tab remained attached and the left elevator balance weight had separated. The left elevator torque arm remained attached with the aft portion of the control rod still attached. The right wing had fragmented in multiple locations and the right flap had separated into two main pieces which remained attached. The right aileron had fragmented and a portion remained attached to the wing. The right wing tip had separated and was impact damaged with the fuel cap still attached. The left wing was impact damaged with the left outer wing and tip separated at mid aileron. The left inboard aileron remained attached with the aileron trim tab still attached. The cockpit exhibited substantial crushing damage.

The airplane's flight control cable system was examined and control cable continuity was verified from all control surfaces to the cabin area of the airplane. Due to the amount of damage to the cockpit, verification of yoke and rudder pedal continuity was not possible. All of the identified breaks in the airplane control system were consistent with impact damage or recovery efforts.

The left engine was impact damaged with one magneto separated. The propeller hub remained attached and all three propeller blades had separated near the blade roots. One blade tip had separated. The right engine was impact damaged and the right propeller had separated with the propeller flange. One propeller blade separated and was not observed. The on-scene engine examination consisted of removal of cowling and airframe components to enable shipping for further examination at the manufacturer's facility, and a borescope examination of the cylinders. The borescope examination did not reveal any anomalies.

Functional testing of the airplane's flight instruments, avionics, and autopilot system was not possible due to the extent of the damage incurred during the impact.

During a subsequent examination, the left propeller was disassembled and no evidence of preimpact malfunction or failure was detected. It was not possible to determine the impact blade angle from impact witness marks. The right propeller was not disassembled. The propeller assembly contained a large high compression spring and the mechanism for s...