Audio recordings and phone calls passengers made provide us the primary data of what happened on United Airlines Flight 93 when it was hijacked at 09:28 a.m. 11 September, 2001. The cockpit voice recorder began recording when the hijackers entered the cockpit of Flight 93. Starting at 09:30, Passengers and crew began making phone calls to officials and family members using GTE airphones and mobile phones. Altogether, the passengers and crew made 35 airphone calls and two cell phone calls from the flight. Ten passengers and two crew members were able to successfully connect, providing information to family, friends, and others on the ground. Through their phone calls, passengers on UA93 heard about the crash of other three planes and decided to fight against the terrorists. The passengers bravery and love of their family are recorded in the audio recordings, the transcripts and recalls of their families. It is through the direct valuable sources, the story of United Airlines Flight 93 is told and remembered.    

--Flight Audio Recordings

First Mayday call

https://en.wikipedia.org/wiki/File:Mayday1.ogg

First Mayday call by pilots on board United Airlines Flight 93 at the time of hijacking. This was released by the government in the compendium of evidence used during the trial of Zacarias Moussaoui.

At 09:28:17, Captain Jason Dahl began shouting, "Mayday! Mayday! Mayday!" over the radio amidst sounds of violence. A Cleveland Air Traffic Controller replied, "Somebody call Cleveland?" but received no reply.

Second Mayday Call

https://en.wikipedia.org/wiki/File:Mayday2.ogg

Second Mayday call by pilots on board United Airlines Flight 93 at the time of hijacking. This was released by the government in the compendium of evidence used during the trial of Zacarias Moussaoui.

Thirty-five seconds after the first Mayday call, the crew made another transmission. Someone in the cockpit shouted, "Mayday! Get out of here! Get out of here!”

The flight recordings suggest that Captain Jason Dahl was still alive on the floor of the cockpit after the hijackers took over the plane, as sounds of moaning can be heard and the hijackers were rebuking someone in the cockpit. Dahl's wife believes that Dahl took actions to interfere with the hijackers, including putting the plane on autopilot just before the hijackers took over, and switching the output of the pilots' microphones from the cabin address speakers to the radio transmitter so that Jarrah's attempts to communicate with the passengers would instead be heard by air traffic controllers. Dahl's maneuver enabled the message to go the air traffic control towers and not to the passengers.

First Announcement

https://en.wikipedia.org/wiki/File:Ziad1.ogg

First announcement made by hijacker pilot Ziad Jarrah when he assumed control of United Airlines Flight 93. This was released by the government in the compendium of evidence used during the trial of Zacarias Moussaoui.

The cockpit voice recorder began recording the final 30 minutes of Flight 93 at 09:31:57.At this moment, it recorded Jarrah announcing, "Ladies and gentlemen: here the captain. Please sit down, keep remaining seating. We have a bomb on board. So sit."

Second Announcement

https://en.wikipedia.org/wiki/File:Ziad2.ogg

Second announcement made by Ziad Jarrah when he was at the controls of United Airlines Flight 93. This was released by the government in the compendium of evidence used during the trial of Zacarias Moussaoui.

At 09:39, two minutes after Flight 77 impacted the Pentagon, air traffic controllers overheard Jarrah say, "Here's the captain: I would like to tell you all to remain seated. We have a bomb aboard, and we are going back to the airport, and we have our demands. So please remain quiet."

United Airlines Flight 93 Traffic Recording

https://www.youtube.com/watch?v=4HoGrkNNgB4&nohtml5=False

Recording of radio communications between United Air 93 and Cleveland Center on September 11, 2001.

A Cleveland Air Traffic Controller replied, "Somebody call Cleveland?" after the first Mayday Call by pilots but received no reply. The recording from the cockpit also including Jarrah’s two announcements when he was at the controls of United Airlines Flight 93. But air traffic controllers did not hear from the flight again after the last announcement made at 09:39 a.m.

Full Transcript of the recording:

http://i.a.cnn.net/cnn/2006/images/04/12/flight93.transcript.pdf

"United Airlines Flight No.93 Cockpit Voice Recorder Transcript" (PDF). CNN. April 12, 2006. Retrieved July 4, 2009.

--Phone Calls

Transcript of Tom's Last Calls to Deena

http://www.tomburnettfoundation.org/transcript.html

Tom Burnett made several phone calls to his wife beginning at 09:30:32 from rows 24 and 25, he explained that the plane had been hijacked by men claiming to have a bomb. He also said that a passenger had been stabbed with a knife and that he believed the bomb threat was a ruse to control the passengers. During one of Tom Burnett's calls, his wife informed him of the attacks on the World Trade Center and he replied that the hijackers were "talking about crashing this plane. ... Oh my God. It's a suicide mission." He began pumping her for information about the attacks, interrupting her from time to time to tell the others nearby what she was saying. He ended his last call by saying, "Don't worry, we're going to do something."

Jeremy Glick called his wife at 09:37:41

Glick told his wife the flight was hijacked by three dark-skinned men that looked "Iranian", wearing red bandanas and wielding knives. Glick remained connected until the end of the flight. He reported that the passengers voted whether to "rush" the hijackers.

http://govinfo.library.unt.edu/911/report/911Report_Ch1.htm

Message left by pregnant passenger Lauren Grandcolas at 09:39:21

Passenger Lauren Grandcolas called her husband twice, once before takeoff and once during the hijacking. He missed both of her calls.

"Jack, pick up sweetie, can you hear me? Okay. I just want to tell you, there's a little problem with the plane. I'm fine. I'm totally fine. I just want to tell you how much I love you."

http://edition.cnn.com/TRANSCRIPTS/0112/28/ltm.16.html

Flight attendant Sandra Bradshaw called her husband at 09:50:04

Bradshaw told her husband she was preparing scalding water to throw at the hijackers. When the hijackers decided at 09:55:11 to direct the plane toward Washington, D.C. Bradshaw, on the phone with her husband, said "Everyone is running up to first class. I've got to go. Bye."