Cooperateresearch mentions the "simulation" here:-
The "exercise", by CIA man Fulton and his team was carried out at THE National Reconnaissance Office (NRO), just four miles from where Flight 77 took off (to return and hit the Pentagon).
It's worth adding that the "exercise" was scheduled to start *WITHIN FIVE MINUTES* OF FLIGHT 77 BEGINNING ITS SUSTAINED DEVIATION from its scheduled course and doubling back to Washington.
This must push the plea of "coincidence" way into the realm of incredibility. ....