N333LM

HISTORY OF FLIGHT

On May 29, 1996, at approximately 1835 central daylight time, a Piper PA-31T, N333LM, owned and operated by Mid South Engineering Company, Hot Springs, Arkansas, was destroyed after impacting terrain shortly after take off from Malvern Municipal Airport, Malvern, Arkansas. All 5 occupants, the airline transport rated pilot and 4 passengers, were fatally injured. Visual meteorological conditions prevailed for the Title 14 CFR Part 91 flight. A flight plan was not filed.

The aircraft had just completed scheduled maintenance by a facility located at the airport. According to maintenance manager, the pilot invited 4 mechanics (all of the mechanics participated in the scheduled maintenance and were friends of the pilot) from the facility to join him for the routine post maintenance acceptance flight. The manager reported that he observed the aircraft execute a ground run up and taxi onto runway 21. After observing what he described as a normal take off roll, he went inside a hangar (he did not witness the take off or initial climb). Shortly thereafter, the aircraft impacted terrain approximately 1 1/2 miles south of the departure end of the runway.

Two witnesses who heard, but did not see the aircraft, were interviewed and provided statements to the investigator-in-charge. While working in their yard, approximately 3/4 miles from the departure end of the runway, they heard the aircraft's engine noise. One of them described the noise as being "very loud." The other described the engines as being "wound out" and at "full speed." Both witnesses stated that they routinely hear engine noise as airplanes either land or depart from the airport. No other airplanes were reported to be in the vicinity at the time of the accident.

Two eye-witnesses were interviewed and provided statements. One of these witnesses, located approximately 1/2 miles south of the accident site, stated that he "heard the plane coming." After looking up, he observed the aircraft "flying level" toward him, and "then it flew straight up, and the engines got louder." He recalled that he "could see the bottom of the plane", and then "it fell to the left and went behind the trees." After hearing a "noise", he observed "smoke" and then called the police. Another eye-witness, located approximately 1/2 mile southeast of the accident site, stated that she heard a "really strange sounding" airplane (similar to airplanes she heard on "cartoons" when they were "spiraling to the ground"). She then observed the "aircraft heading for the ground" in a nose low attitude. She stated that the aircraft disappeared behind trees during the descent and did not observe the impact.

PERSONNEL INFORMATION

The pilot was employed by Mid South Engineering as the chief corporate pilot since 1991, and held a current airline transport pilot certificate with type ratings in the CE-500, DA-10, and DH-4. He was a certified flight and instrument instructor in single and multi-engine airplanes. His personal flight logs were not recovered. However, as of his last medical examination, performed on July 12, 1995, he had a total of 7,500 hours of flight time. Additionally, the operator reported that he had approximately 5,000 hours of multi-engine flight time (1,700 hours of which were in turbine powered aircraft). The operator also reported that the pilot completed PA-31T initial training on November 19, 1991. He completed PA-31T refresher training on December 13, 1993, and most recently on December 13, 1995 (certificates attached to this report). According to FAA records, the pilot did not have any flight violations.

Both the company president and the maintenance facility manager stated that they felt that the pilot was "safe and responsible."

AIRCRAFT INFORMATION

Manufactured in 1979, the Piper PA-31T, serial number 31T-7920052, was maintained on a 2 Event, 100 hour cycle maintenance program contracted to D-1 Aviation Inc., Malvern, Arkansas. On the day of the accident, Event 1 of the 100 hour cycle was completed. Log book entries had not been completed, however, the maintenance manager stated that the aircraft was airworthy and had no outstanding discrepancies prior to the flight. According to maintenance records, the last Event 2 inspection was completed on December 28, 1995. The last airframe log book entry (April 1, 1996) prior to the accident was for an inoperative cabin heater. The airframe total time as of this log entry was 4,483.5 hours. The exact total time of the airframe at the time of the accident could not be retrieved due to impact damage to the Hobbs meter and tachometer.

The two PT6A-28 model engines (S/N's 51985 and 51983) were original equipment, and were last overhauled in May, 1991. Both engines had total times of 4,453 hours each, as of their last recorded maintenance performed on March 21, 1996. According to maintenance records, the engines were in service for 1,066 hours since overhaul to March 21, 1996. According to company records, both engines were independently subject to scheduled Spectrographic Oil Analysis Programs (SOAP). These data, provided by the company, did not show any abnormal trends.

The two Hartzell model HC-B3TN-3B propeller assemblies (Hub S/N's BU9706 and BU9701) were original equipment. According to maintenance records, S/N BU9706 hub assembly was last overhauled on January 13, 1993. S/N BU9701 hub assembly was last overhauled on July 7, 1992.

Inspection of the airframe, engine and propeller maintenance records revealed no discrepancies of uncorrected maintenance defects. According to the records, the aircraft was in compliance with all applicable Airworthiness Directives.

COMMUNICATIONS

There were no reported communications with the aircraft. The departure airport did not have a tower facility.

WRECKAGE AND IMPACT INFORMATION

The accident site was located approximately 1 1/2 miles southeast of the departure end of runway 21. The terrain was sloping upward away from the airport, and heavily wooded with small pine trees and brush. The entire wreckage area, including ground impressions and debris, encompassed a linear area approximately 80 feet long and 30 feet wide. The center line axis along the energy path was oriented approximately 082 degrees magnetic. The initial impact point was discovered to be a 2 foot deep ground impression, measuring approximately 5 feet wide, and 7 feet long. Evidence at the site (damaged bushes) showed that, after the initial impact, the aircraft slid forward along the energy path for about 80 feet and was consumed by a post impact fire. The main wreckage consisted of the fuselage, both wings, and both engines with nacelles (the empennage was found completely separated from the fuselage and was located between the initial ground impression and the main wreckage). A summary of the on site findings are presented below and are listed as they were found in-situ along the energy path.

The left propeller cylinder and piston assembly were found separated (fractured) from the propeller hub spider assembly, approximately 10 feet forward of the initial ground impression and 10 feet to the left of the energy path center line. The hub and all three propeller blades (attached to the hub) were found adjacent to the main wreckage near the engine reduction gearbox. One of the blades exhibited bending aft (approximately 30 degrees) and was twisted toward low pitch from mid span to the blade tip. The second blade exhibited bending aft from the inboard portion of the de-ice boot and was twisted toward low pitch. Approximately 1/4 of the blade span (outboard to the tip) was not recovered and appeared to have been consumed by the post impact fire. The third blade was bent slightly aft. Approximately 2/3 of the outer portion of the span was not recovered and appeared to have been consumed by the post impact fire. All three of the left propeller blade faces exhibited chordwise scoring.

The right propeller assembly was found embedded in the ground, approximately 15 feet forward of the initial ground impression and 15 feet to the right of the energy path center line. The piston was found extended and the pitch change links were fractured. One of the propeller blades was found separated from the hub (fractured). The blade was exhibited bending slightly aft and was twisted toward low pitch from approximately 1/3 span outboard toward the tip. The two other blades were found attached to the hub. One of the attached blades was free to rotate by hand within the blade clamp. This blade exhibited bending forward from approximately 1/4 span and was twisted toward low pitch. The second attached blade was found turned approximately 180 degrees within the blade clamp, and was twisted toward low pitch from approximately 1/3 span outboard to the tip. All three of the right propeller blades exhibited chordwise scoring.

The empennage, including elevators and vertical stabilizer, was found approximately 30 feet forward of the initial ground impression along the energy path. As previously stated, it was completely separated from the fuselage. The break occurred at about Flight Station 317, with a portion of the bulkhead and outer skin remaining with the fuselage. Control cables to the elevators and rudder showed evidence of tension overload near the structural separation area. Cable continuity was established from the cable breaks rearward to the rudder and elevator control surfaces. Flight control stops for the rudder and elevator were intact. Both elevator trim tabs were aligned with the elevator surface in the "neutral" position. The rudder trim drum shaft was observed to have a forward extension of 1.25 inches with 8 jackscrew threads visible. This trim reading indicates a near "neutral" setting.

The main wreckage, as previously stated, was found approximately 80 feet forward of the initial ground impress...