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piece of wreckage found along this path was approximately 17,400 feet from the crater. All pieces from there along this path to about 7,500 feet from the crater were very low in density, consisting of items such as Seat Occupied cards, cabin air conditioning insulation, fragments of thin skinned stringers, etc. In an area about 1,600 feet long, centered approximately 4,300 feet from the impact crater, the wreckage consisted mainly of more dense pieces, such as center section fuel cell bags and backing strips, horizontal tail leading edge deicer strips, etc. Nearer to and still northeast of the crater there were numerous pieces of still denser wreckage, such as fragments of wing structure surrounding the center section fuel tank, air conditioning packs including the primary heat exchangers, the right horizontal stabilizer, etc. Within a radius of 360 feet from the main impact crater, there were numerous pieces of dense wreckage including parts of the right wing and fuselage, right main landing gear, horizontal and vertical tail surfaces and the Nos. 2 and 3 engines and pods. The crater contained most of the fuselage and left inner wing wreckage, the left main gear and the nose gear.
In two small wreckage concentrations separate from the two previously mentioned paths, there were ten pieces, consisting of the Nos. 1 and 4 engines, pylons and sections of their cowling. The No. 1 engine and pylon assembly was approximately 1,925 feet on a bearing of 13 degrees from the impact crater. None of the other eight pieces were more than 165 feet from the corresponding engine.
Examination of the wreckage in conjunction with consideration of the wreckage distribution disclosed multiple indications of lightning damage, fire and disintegration in flight, which will be discussed in following paragraphs. However, the four powerplant pods in their entirety yielded only evidence of their having separated in flight due to excessive load factors, without engine failure or malfunction prior to separation.
A majority of the components of the various systems within N709PA were destroyed. The recovered portions of the hydraulics and electrical systems showed no evidence of operational distress or pre-impact failure. The fuel dump valves were determined to be in the "closed" position.
A portion of the trailing edge of the left horizontal stabilizer was burned through and the paint was blistered along the entire upper and lower surfaces of the trailing edge. There was molten aluminum alloy splattered on the forward upper surface of the leading edge of the stabilizer which was determined to have been deposited in flight. There was no evidence of fire damage on the right horizontal stabilizer. The left side of the vertical tail and aft fuselage were extremely scorched by exposure to fire in flight. Numerous instances of in-flight fire were found on the recovered wreckage of the lift inboard wing aft of the rear spar, although most of the external skin remained unidentified. In-flight fire damage was noted on the three steel tracks for the inboard flap on the track at the inboard end of the outboard flap, the inner end of the outboard flap, fragments of the spoilers, dump chute components, coverlip doors, and fragments of the fore flaps.
The high frequency (HF) radio antenna had separated from the vertical tail section and exhibited numerous tiny pock marks which were dull in appearance.
The complete left wing tip, with portions of the left outer aileron and spar webs still attached, was found approximately 1.8 miles east-northeast of the main
