Twenty-five years after the September 11, 2001 attacks, Charles Wolf is reflecting on the loss of his wife, Katherine, and the chilling moments leading up to her death.

Charles and Katherine Wolf met in New York in 1988. He described their meeting as love at first sight, stating, "There was no parting us." They married and built a life together, with Katherine taking Charles to visit the UK in 1989.

On the morning of September 11, 2001, Charles kissed his wife goodbye from their New York City apartment at 8:06 a.m. EDT. Less than 40 minutes later, a jet crashed into the 97th floor of the World Trade Center tower, where Katherine had recently begun a new job.

As a trained pilot, Charles recognized the sound of the aircraft. "I knew instantly when it flew over my building - our apartment building - that it was a twin engine jet at full throttle," he recalled. His immediate recognition of the plane's aggressive flight led him to call the FBI. He informed them, "That was no accident, that was deliberate."

A year later, an FBI agent confirmed to Charles that his call was the first indication authorities received that the plane's trajectory was not accidental. The attack claimed Katherine's life along with thousands of others in the deadliest terrorist assault on U.S. soil. M