Abstract: Were there warnings of a second and third incoming plane, did they play a role for the decision to evacuate the Towers,
what's the official point of view.

You may know John Schroeders appearance in Loose Change FC.

Firefighter Schroeder made it all the way up to the 23rd floor before barely hearing on the failing radios that another plane was coming in.

http://loosechange911.blogspot.com/2007/08/interview-with-john-schroeder-fdny.html

Now I've had a hard dispute over this with some sort of a debunker, who claims, that there is no hint for such a warning. Nor in the 911CR neither in any other radio transmission records. Here are the links he presented:

http://www.fdnytenhouse.com/911/story01.htm

Manhattan Fire Dispatch 8:46 - 9:34 a.m.:
http://www.radiofirehouse.com/broadcast/wp-content/2005/fdny/FDNY_Tape15.mp3

Fire Brooklyn Dispatch Radio 8:47 - 9:35 a.m.:
http://www.radiofirehouse.com/broadcast/wp-content/2005/fdny/FDNY_Tape9.mp3

All other radios transmissions about 6 hours to 9/11 afternoon
http://cms.firehouse.com/content/section/content.jsp?sectionId=41

http://www.whatreallyhappened.com/flight93radio.php

See original for MP3 links.

THE FINAL MOMENTS OF FLIGHT 93 - A CLOSE LOOK AT THE RADIO TRAFFIC

To start with, here is an mp3 recording of the air traffic controllers during the moments leading up to the crash of United Flight 93. It lasts 3 minutes and 58 seconds.

In the tape, there are two communications which purport to be from the hijacked aircraft.

The first transmission is at 1 minute and 14 seconds into the recording. [mp3 download]

The second transmission is at 2 minutes and 3 seconds into the recording. [mp3 download]