Despite predictions, events seldom occur precisely as expected. The calculated breakup altitude of Skylab was based on its intended structural strength specifications. However, the actual vehicle was stronger than the specified strength requirements.
Mgrs. & Controllers Monitor Re-entry
Garriott with Oxygen Tank Debris. Credit David Hitt
The official decision to proceed with the Skylab reboost mission was made on September 1st 1977, initiating a two-year preparation period for the development and production of the required hardware and systems.