N988PC

HISTORY OF FLIGHT

On June 20, 2008, about 1210 eastern daylight time, a Piper PA-18-150, N988PC, was substantially damaged when it impacted terrain at Placid Lakes Airport (09FA), Lake Placid, Florida. The certificated private pilot and the passenger were fatally injured. The aerial observation flight was operated under the provisions of 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed for the local flight, and no flight plan was filed.

The airplane was based at 09FA. The accident pilot began fueling the airplane shortly before 1100, but at some point the fuel nozzle broke, and fuel was spilled on the airplane. The husband of the airport manager reported that he was notified by his wife at 1100 that the nozzle was broken, and that he completed the repair by 1130. Witness reports indicated that the airplane departed on the accident flight shortly after being fueled, with the express purpose of locating a specific bear tracking collar, and that the accident flight was only about 1/2 hour in duration.

The husband of the airport manager was the only person to witness the return of the airplane to 09FA. He reported that he saw the airplane fly south along the north-south runway at a height which he variously estimated to be between 40 and 100 feet above the ground. When the airplane neared the south end of the runway, the witness heard the engine rpm increase, and saw the airplane conduct an abrupt pull up, followed by a turn to the left and a rapid descent. He described the maneuver as a "drastic left bank." At that point, the airplane disappeared from his view behind a treeline, and the witness heard a "thud." He subsequently drove to the south end of the runway, and saw that the airplane had impacted the ground. The pilot was seated in the front seat, and the passenger was seated in the rear seat.

PERSONNEL INFORMATION

Pilot

Examination of the pilot's logbook revealed that he had accumulated approximately 1,250 total hours of flight experience, including 700 hours in complex and/or high performance airplanes, and 420 hours in the accident airplane. The most recent entry in the logbook was dated April 7, 2008. His most recent flight review was accomplished on August 1, 2007, and his most recent third-class medical certificate was issued on July 16, 2007.

Passenger

The passenger was a University of Kentucky faculty member who was engaged in bear tracking studies. His research activity in Florida was associated with the Archbold Biological Station near Placid Lakes, and he regularly utilized aircraft to assist in his research. He was not a certificated pilot, and according to his wife, he had never obtained any flight instruction.

AIRCRAFT INFORMATION

The airplane was of a high wing, fixed-gear, tailwheel configuration, and the exterior surfaces were finished in a bright yellow color. According to Federal Aviation Administration (FAA) records, the airplane was manufactured in 1988, and changed ownership several times before being registered to a relative of the accident pilot in 2000. According to the FAA records, the airplane contained a significant number of post-delivery modifications. These modifications included additional antennae, as well as vortex generators and other aerodynamic alterations. Examination of the airplane's airworthiness documents that were maintained by the FAA revealed that the most recent documentation, dated February 1998, concerned the installation of a 180 horsepower engine and vortex generators on the wings.

According to the airplane manufacturer's documentation, the airplane was equipped with one trailing edge flap on each wing. The cockpit flap handle was located near the front left side of the pilot's seat. The flap handle was used to mechanically extend the flaps via cable, and springs and airloads provided the forces to retract the flaps. A pawl that was activated by a spring-loaded button in the top of the flap handle, and which contacted a plate with fixed detents, served as the positioning and locking mechanism for the flap handle and the flaps. The manufacturer's guidance specified that the flap cable was attached to the flap handle with a shackle that was secured by a bolt, castellated nut and cotter key. The flap cable was routed from the handle aft along the left cabin, to a point behind the passenger seat, then up to a cable juncture at the top of the fuselage. A separate cable segment was routed from the juncture to each of the two flaps.

The engine was a Lycoming IO-360-C4P, and had accumulated a total of 759.6 hours. The most recent annual inspection was completed on February 25, 2008, and at that time the maintenance records indicated a tachometer time of 1,160.1 hours. At the time of the accident, the tachometer registered 1,223.1 hours.

METEOROLOGICAL INFORMATION

The 1205 surface weather observation at an airport about 30 miles east of 09FA recorded winds from 320 degrees at 4 knots, scattered clouds at 3,900 feet, temperature 32 degrees C, dew point 22 degrees C, and an altimeter setting of 30.06 inches of mercury. The visibility was not included in this observation, but observations at the same airport 20 minutes prior to and after this observation indicated 10 miles visibility.

COMMUNICATIONS

No records of any communications between the accident airplane and any air traffic control facilities were located.

AIRPORT INFORMATION

09FA was situated at the western edge of the community of Placid Lakes. The single runway, 18/36, was asphalt, and measured 4,800 feet long by 50 feet wide. The elevation was 130 feet above mean sea level. The hangars and fueling ramp were located near the north end of the runway. There were no buildings along the southernmost thousand feet of the runway.

WRECKAGE AND IMPACT INFORMATION

The airplane came to rest in a grassy area approximately 940 feet north of the south end, and 130 feet east, of the runway. The fuselage was in a near-vertical, nose-down attitude, with the vertical stabilizer pointed southeast. The nose of the airplane was embedded approximately 16 inches into the ground. The forward fuselage exhibited significant crush damage in the aft direction, and the aft fuselage exhibited moderate twisting and bending. The cabin volume was significantly reduced by impact forces. All flight control surfaces were accounted for at the scene. The horizontal and vertical stabilizers, and their respective control surfaces, were intact. There was no fire.

According to the police report, the only hardware-type personal effect recovered from the airplane was a Nikon D-300 digital camera, which belonged to the passenger. Photographic and email evidence indicated that the passenger also carried a "Telonics TR-5" receiver, which was approximately the size of a 1-quart oil container, and which was found in its case.

The camera memory chip, and the engine and airframe were temporarily retained by the National Transportation Safety Board (NTSB) for further examination.

Airplane Examination

On June 26, 2008, FAA and Piper personnel examined the airplane in a hangar at 09FA. The left and right wings had been cut away and detached from the fuselage by recovery personnel. All flight controls were present, and were attached to their respective airfoils.

The cockpit and cabin area exhibited severe crush damage in the aft direction. Some fuselage structural tubes had been cut by recovery personnel. The aft fuselage was twisted and buckled downwards at a point approximately half-way between the cabin and empennage. The landing gear remained attached to the fuselage frame, and exhibited impact damage in the aft direction.

The leading edges of both wings were crumpled aft for the full span of each wing. The forward and aft lift struts were attached to their respective wings, and bent at the jury strut attach areas. The flaps and ailerons remained attached to their respective wings, and both exhibited impact damage. The left and right fuel tanks were crushed and devoid of fuel. The left fuel cap was present, and the right tank fuel filler neck, with the cap attached, was separated from the tank.

The vertical fin and horizontal stabilizers remained attached to the fuselage. The fin, rudder, stabilizers and elevators were intact. Examination of photograph evidence revealed that the left elevator was intact subsequent to the accident, but after it was transported to the hangar, the inboard trailing edge was observed to be bent up approximately 15 degrees.

Flight control continuity was established for all primary flight controls, except for impact- and recovery-related separations. Control cable continuity for the flaps was established from the control surfaces to the cuts that were made by recovery personnel, and from the cuts to the cockpit region.

The flap handle exhibited impact damage, and its setting could not be determined. The flap control cable was not connected to the flap lever. The cable shackle and the corresponding attach point on the flap handle appeared undamaged. The hardware used to attach the shackle to the flap handle was not located. The investigation was unable to locate any recovery personnel who disconnected the cable from the flap handle, or who were aware of anyone else taking such an action.

When it was recovered, the engine remained attached to its mount, the mount remained partially attached to the fuselage frame, and the propeller remained attached to the engine.

Engine Examination

On July 9, 2008, FAA and Lycoming personnel examined the engine at the storage facility in Groveland, Florida. Both propeller blades exhibited chordwise scoring, and were bent aft and slightly twisted. The propeller was removed from the engine for examination purposes, and the engine was partially disassembled. The spark plugs, valve covers, and accessory components were removed. Borescope examination of the cylinders and valves revealed no anomalies. The combustion cham...