Very interesting excerpt from a biography of Rowan Williams- He was at "Groud Zero".
The London Times
On September 11, 2001, Rowan Williams was due to address 22 spiritual directors from across the US in a church-owned building next to Holy Trinity, Wall Street [New York], on “the shape of a holy life”, and reached the venue, 74 Trinity Place, at 8.35am. His host was the Rev Fred Burnham, director of the Trinity Institute, an educational foundation attached to the neighbouring church. The two went up to the 21st floor. Burnham was sitting in his office when the World Trade Centre's north tower was hit at 9.03am; and even though Flight 11 came from the opposite direction (Trinity Place is south of Ground Zero), the noise sounded like a sonic boom. Burnham raced to the room where Rowan was and cried that “some cowboy” had just gone through the sound barrier. Then came a scream: one of the secretaries could see what had happened through her window. Burnham, Rowan and the others joined her to look. Though aghast, they assumed that the crash was accidental.
Its all here- (and worth the read)