NORAD generals lied to the 9/11 Commission about the flight times.
The Washington Post, to its credit, published this news article on August 2, 2006 and it is still up on their website as of January 3, 2014.

Here is the link:

In case they remove it you can download this as a NORAD deception.

This video shows one of the strongest statements ever made by a U.S. Senator about the lies in the 9/11 Commission report. Senator Mark Dayton of Minnesota cites some of the specifics and lays the blame on lies, not incompetence.

The 9/11 Commission’s final report attempted to cover NORAD’s behind, a common theme in the 9/11 statements by the government, by claiming that NORAD was totally unprepared for the attacks.

There is evidence that they were prepared.

In particular General Eberhart told the 9/11 Commission that the standard protocol (for intercepting hijacked airplanes) in place as of 9/11 were adequate and would have enabled NORAD to intercept and, if necessary, shoot down the hijacked planes IF ONLY NORAD had known about the hijackings in time.

Separately the FAA told the 9/11 Commission that within minutes of the 2nd plane strike into the World Trade Center they established a phone bridge and provided current (“real time”) information to everybody on the phone bridge about all the flights of interest.  NORAD was on that phone bridge.

In other words NORAD was notified and did know in time about the hijacked planes.  In that case they should have intercepted the planes, as Eberhart said they could have if they had known in time.

You can download the transcript of these conversations with the 9/11 Commission from this page.

NORAD standard protocol on September 11