Where does the 1700 feet come from? The height gain was reported in the 3 - 4 thousand range. Even so, the angle change for 1700 or 3000 - 4000 feet is small compared to the 13000 feet initial altitude. Would hardly explain witnesses statements that object went upward in some cases from the surface.
It was interpolated from radar data and debris fields that were used to reconstruct the path of flight after the initial explosion.
"The height gain was reported in the 3 - 4 thousand range. "
Not by the NTSB, who conducted the investigation. They estimated the aircraft climbed 1200-2200ft.
"Would hardly explain witnesses statements that object went upward in some cases from the surface."
Very few of the witnesses reported seeing anything rising from the surface. And none of them reported seeing the following....
"Investigators determined that if witnesses had observed an actual missile attack on TWA flight 800 (beginning about the time that an airborne missile would have become visible to the time that the wreckage from TWA flight 800 fell into the ocean), they would have seen the following: (1) a light (the burning of the missile motor) ascending very rapidly and steeply for about 8 seconds (this rapidly moving light, which would have been visible for at least 12 nm575 from the launch point, would not descend like a firework or flare); (2) the light disappearing576 for up to about 7 seconds;577 (3) upon a missile (or warhead fragment) striking the airplane and igniting the fuel/air vapor in the CWT, another light (flames coming from the CWT), moving considerably slower and more laterally than the first light (although ascending somewhat for a short time), for about 30 seconds; (4) this light descending while simultaneously developing into a fireball falling toward the ocean."