NTSB Factual Report

HISTORY OF FLIGHT

On September 20, 1998, about 1431 eastern daylight time, a Piper Aerostar 600, N17MT, registered to a private individual, crashed shortly after takeoff from the Grand Strand Airport, North Myrtle Beach, South Carolina. Visual meteorological conditions prevailed at the time and an Instrument Flight Rules (IFR) flight plan was filed for the 14 CFR Part 91 personal flight. The airplane was destroyed by impact forces and a postcrash fire. The commercial-rated pilot and three passengers were fatally injured. An individual on the ground who was injured by fire, subsequently died 6 days after the accident. The flight originated about 3 minutes earlier.

According to a line service person employed by Ramp 66, North Myrtle Beach, the airplane had been hangared since arrival 3 days earlier and before the flight departed, he noted that the pilot was seated in the left front seat and a younger looking person of the three passengers was seated in the right front seat. Both engines started "ok", and the pilot waited on the ground for about 20-25 minutes with the engines idling. During that time he observed the pilot wiping sweat from his face using a cloth; he was doing something on the panel, and he put on his headset and kneeboard. He reported that he drove a golf cart to a corner of the field for the purpose of watching the takeoff, and while there, the airplane arrived at the run-up area. He did not hear an engine run-up, and noted that the engines remained at idle while the airplane was stopped there for about 5-6 minutes. He then positioned his cart to a point about midfield of the runway to observe the takeoff; the airplane departed with no flaps extended. During the climbout, he observed the landing gear retracting and a slight amount of black smoke trailing the airplane.

Review of a transcription of communications with the Grand Strand Airport Air Traffic Control Tower revealed that at 1420:24, the pilot contacted ground control, requested and received his IFR clearance then at 1421:07, the controller cleared the flight to taxi to runway 23. The pilot was provided the wind and barometric setting information. At 1427:34, the pilot radioed the local controller and advised that the flight was ready for departure on runway 23. The controller cleared the flight to takeoff at 1427:39, which was acknowledged by the pilot 6 seconds later. At 1428:32, the local controller advised the controller from the arrival position of Myrtle Beach Approach Control that "aerostar seven mike tango's rolling...." At 1429:19, the local controller radioed the pilot and advised him "seven mike tango appears to have smoke trailing from your right side." The pilot acknowledged the transmission and at 1429:37, the pilot radioed the local controller and stated "seven mike tango we're going to come around and land." The local controller acknowledged the pilot's transmission and asked the pilot if he was declaring an emergency or did he need any assistance. The pilot replied negative. At 1429:58, the local controller cleared the flight to land on runway 23, which was acknowledged by the pilot. Further transmissions from the pilot recorded on the voice tape were unintelligible. At 1430:53, the local controller advised the approach controller that the airplane had crashed and smoke was observed.

The controller who observed the smoke reported in a personnel statement that "...as the aircraft was passing in front of the tower it appeared to be trailing smoke. I picked up the binoculars and confirmed my observation and identified the smoke as coming from the right engine and smoke was beginning to increase in intensity. I advised the pilot (He was crossing the departure end of runway 23) that the right engine appeared to be trailing smoke...." He later stated that the smoke appeared to be deep gray in color with two dark edges that appeared to be 1 to 1.5 feet apart with distinct separation. He did not see any fire or flames.

Numerous witnesses near the accident site reported observing a low flying airplane with smoke trailing from the right engine. They reported seeing the airplane bank to the left and a pilot-rated witness reported, "...the right engine was trailing smoke the aircraft made a turn to the left as if trying to return to the airport possibly due to the south tower he continued to tighten his turn to the left I told my wife 'he's in trouble' He appeared to stall and went below the tree line...." A copy of his statement is attached. Several witnesses reported seeing the airplane pitch nose down, impact trees then the ground followed by an explosion. One witness reported "...planes engines were at high speed, no smoke, no fire", while another witness reported seeing the plane fly over the ocean and "...it sounded like the engine was cutting out...." Copies of the witness statements are attachments to this report.

PERSONNEL INFORMATION

According to the pilot's second pilot logbook, his total logged flight time was 1,321 hours which included 474 hours in make and model. His first flight in the accident airplane was logged as taking place on March 31, 1998, and he had accumulated a total of 30 hours in the accident airplane. He logged a total of 1,184 hours as pilot-in-command, and 956 hours in multi-engine airplanes. His first pilot logbook was not located. Further information pertaining to the pilot is contained on page 3 of the Factual Report-Aviation.

AIRCRAFT INFORMATION

Current logbook records for the aircraft and engines were not located after the accident. According to a work order and invoice from Flying Tigers, Inc., a maintenance facility that had maintained the airplane, an annual inspection had been performed on January 29, 1998. The airplane total time, and time since major overhaul of the left and right engines at that time were 3,360 hours, 1,307 and 2,030 hours, respectively. The airplane had accumulated approximately 53 hours since the annual inspection at the time of the accident. According to the engine manufacturer, the recommended time between overhaul for the Lycoming IO-540-K1J5 engine is 2,000 hours; compliance is not mandatory.

Logbooks for the right engine which begin with an entry dated May 22, 1979, and end with an entry dated December 3, 1993, were recovered; no further logbooks for the right engine were located. Review of the logbooks revealed several entries which indicate that the exhaust was repaired. The first entry dated April 2, 1980, indicates that the cracked exhaust stacks were repaired, but it does not indicate which side of the exhaust stack was repaired. The second entry dated August 22, 1980, indicates that the left exhaust assembly was repaired. The third entry dated February 5, 1981, indicates that the aft section of the inboard exhaust stack was repaired. The final entry pertaining to repairs of the exhaust system was dated February 21, 1984. The entry indicates that the cracked exhausts were repaired.

Airworthiness directive (AD) 87-07-09, which was issued on May 15, 1987, and applicable to this make and model airplane, required a one time inspection of the exhaust system. An entry in the engine logbook dated October 31, 1987, indicates compliance with the AD. Additionally, Aerostar Service Bulletin No. 920A, dated September 12, 1991, for this make and model airplane by serial number, indicates that the exhaust system is required to be inspected at the next regularly scheduled inspection not to exceed 10 hours, and thereafter each 25 hours time in service. Review of the right engine logbook from that date to the last entry in the engine logbook revealed no entry which specifically states that the inspection was accomplished. Compliance with the Service Bulletin is not mandatory.

According to the president of Flying Tigers, Inc., where the airplane was maintained, he was aware of Service Bulletin 920A, and reported that it was typically accomplished during each engine oil change. He also stated that he had flown the accident airplane for about 22.5 hours from January 1998, to August 1998.

The aircraft maintenance records indicate that the airplane was equipped with a low thrust detector system that was installed on November 25, 1987, in accordance with a Supplemental Type Certificate.

According to the line service employee who witnessed the takeoff, he helped load bags into the airplane and he sat briefly inside the airplane. With respect to the baggage, he noted eight bags of luggage and four sets of golf clubs. One of the bags that he loaded into the aft baggage compartment weighed an estimated 100 pounds. The pilot loaded the golf clubs into the airplane. He thought that each person had two pieces of luggage consisting of a garment bag, and one additional bag that could carry 2-3 days of clothes.

On the day of the accident, at the request of the pilot, the fuselage fuel tank was filled which took 19.6 gallons and 25.0 gallons of fuel were added to each wing fuel tank. A total of 69.6 gallons of fuel were added. According to the fueler, the wing tanks were not full; he could not see fuel in the wing fuel tanks.

According to personnel from Aerostar Aircraft Corporation, with approximately 24 gallons of fuel in the fuselage tank, each wing tank would contain approximately 7 gallons of fuel. The fuel consumption while idling is approximately 3.5 gallons per hour per engine, and the fuel used for engine start and taxi is approximately 5 gallons.

Weight calculations were performed using the last known empty weight of the airplane (4,041.58 pounds per an entry in the aircraft logbook dated May 30, 1986), the usable fuel quantity of the fuselage tank (41.5 gallons), and the usable fuel quantity in the wing fuel tanks (58 gallons total). The calculations also included the weight of the pilot per his last medical application dated October 30, 1997 (203 pounds), the estimated weight of the right front seat occupant (160 pounds), and the weights of Leonard Boyer (186 pounds) and David Boyer (218 pounds), per visits to the same doctor's office 12 and 11 days before the accident, respectively. The calculations also include the weight of the golf clubs and baggage that was damp (197 pounds), the fuel used with the engines idling for 25 minutes (3 gallons), and 5 gallons total used for engine start and taxi. The airplane was calculated to weigh 5,555 pounds at the time of departure. The airplane type certificate data sheet lists the maximum takeoff weight as 5,500 pounds.

According to the Director of Maintenance for Ramp 66, where the airplane was parked, the airplane arrived there on September 18, 1998. There was no record of maintenance being performed while the airplane was at their facility.

METEOROLOGICAL INFORMATION

The Grand Strand Airport surface weather observation taken at 1435, indicates that the wind was from 140 degrees at 6 knots, the surface visibility was 6 statute miles, a ceiling of broken clouds existed at 3,000 feet, the temperature and dewpoint were 82 and 72 degrees F, respectively, and the altimeter setting was 29.94 inHg. Additional weather information may be found on pages 3 and 4 of the Factual Report-Aviation.

COMMUNICATIONS

The pilot was in contact with the Grand Strand Air Traffic Control Tower and transcriptions of communications are attachments to this report.

WRECKAGE AND IMPACT INFORMATION

The airplane crashed in Ocean Creek Resort which was located approximately 2 statute miles and 209 degrees magnetic from the Grand Strand Airport. Examination of the crash site revealed that while on a magnetic heading of about 009 degrees, the airplane collided with several trees then the ground. The airplane came to rest upright on a magnetic heading of approximately 017 degrees, approximately 100 feet from the initial tree impact location. The angle of descent from the first tree impact to the first ground impact approximately 72 feet later was calculated to be approximately 35-40 degrees. The first tree contact occurred with the right wing about 50-55 feet above ground level (agl). Additional tree impacts were noted 40-45 agl, and 30 feet agl. Fire damage to several trees near where the airplane came to rest were noted. A postcrash fire consumed the cockpit, cabin, sections of both wings, and the nose section of the airplane. The right wing outboard of the engine nacelle was separated and found about 17 feet to the right of the centerline of the impact path. Tree leaves near the initial tree impact exhibited fire damage.

All components necessary to sustain flight were in the immediate vicinity of the crash site. The rod ends for the elevator and rudder at the rear bellcranks were connected; the push tubes for all flight controls were destroyed by fire in the cockpit, cabin, and in sections of the wings. The landing gear was determined to be retracted. The left flap actuator was found to be extended 8 1/8 inches which equates to extension between 30 degrees and 45 degrees (full down). The right flap actuator was found to be extended 3 7/8 inches which equates to being between fully retracted and extended 10 degrees. The flap extension at the time of impact was not determined. The rudder trim actuator was found to be extended 3 inches which equates to a tab deflection of between 1.15 degrees to the left and neutral. The right horizontal stabilizer with attached elevator was separated from the airplane with evidence of two tree impacts on the leading edge of the horizontal stabilizer, soot was noted on the stabilizer and elevator. Examination of the fuel selector valve revealed that the left and right fuel shutoff valves were in the "open" position and both fuel crossfeed valves were in the "closed" position. The left propeller was found in line with the engine; two of the propeller blades were bent beneath the engine. The propeller hub was fractured forward of the propeller hub engine mounting flange. The right propeller was attached to the engine. The interior surface of the right lower engine cowling was observed to be sooted with deep, non-sooted scratches. The interior surface of the right upper engine cowling exhibited heavy sooting. The engines were removed from the airframe for further examination.

Examination of the left engine revealed crankshaft, camshaft, and valve train continuity. Thumb compression for each cylinder was confirmed. The magnetos, engine driven fuel pump, oil filter adaptor housing, and the aft oil cooler were destroyed by fire. The propeller governor which was found positioned at the high rpm stop, was removed for further examination. Visual examination of the spark plugs revealed a light tan color. All fuel injector nozzles were clear of obstructions.

Examination of the left propeller revealed that the No. 1 propeller blade was bent aft about 60 degrees beginning at the midspan with evidence of leading edge twisting towards low pitch. A gouge on the leading edge of the blade was noted about 11 inches from the blade tip. The No. 2 propeller blade was bent aft with the leading edge near the blade tip twisted towards low pitch and the No. 3 propeller blade was bent slightly aft with the leading edge twisted towards low pitch. Examination of the preload plates of each propeller blade for impact signatures to determine propeller blade angle at the time of impact was accomplished. The propeller blade angles for the Nos. 1 and 3 propeller blades were between the low and high pitch settings and near the low pitch stop setting, respectively. The propeller blade angle for the No. two propeller blade could not be determined.

Bench testing of the heat damaged left propeller governor revealed that the high rpm stop was recorded to be 1,960 rpm (specification range 2420 + or - 10 rpm). The pressure relief was recorded to be 195 psi (specification range 275-300 psi). Oil leakage was noted from the base during bench testing and the flyweight was noted to be heat damaged. Disassembly of the governor revealed that the rack and spool was bent and was restricted in movement. The discrepancies noted were attributed to impac

NTSB Probable Cause

The pilot's failure to maintain airspeed (Vs) during a single engine approach resulting in an inadvertent stall. Factors contributing to the accident were a fatigue crack in the exhaust pipe in the right engine, the aircraft weight and balance was exceeded, degraded aircraft performance and the pilot's diverted attention.