[Harrison Bergeron]

"...the plane's flight data recorder, stored in the tail, quit working while the aircraft was still 2,900 feet in the air, "

These devices tend to stop recording data when they become seperated from the airframe.

[El Gato]

These devices tend to stop recording data when they become seperated from the airframe.

The FDR is not located in the tail fin, just in the tail area somewhere. The veritical fin (stabilizer) fell off, not the entire tail, which would include the horizontal stab as well as the aft end of the fuselodge.