Thousands of innocent lives were lost on Sept. 11, 2001 when four airliners were hijacked and turned into weapons of terror. It's a tragic day that's forever burned into the memories of Americans – like the bombing of Pearl Harbor or the assassination of President John F. Kennedy – who could only look on in shock and horror as the day's events unfolded.

Two of the planes that day crashed into the World Trade Center's Twin Towers in New York City while another hit the Pentagon in Arlington, Virginia. The fourth plane was headed for Washington, D.C., but did not hit the terrorists' intended target.

The passengers and crew on that fourth plane, United Airlines Flight 93, made 37 calls to friends, family members and emergency operators after they learned about the earlier attacks on the World Trade Center and Pentagon. Passengers fought back against the hijackers and the plane ultimately crashed into a field near Shanksville, Pennsylvania, but the sacrifice of those on board likely saved other people's lives.

Many of the phone conversations made by those trapped on the hijacked planes have been made public, mainly through evidence presented in the trial of Zacarias Moussaoui in 2006, which included FBI interviews with recipients of the calls and notes from the published report of the 9/11 Commission. Details from each of the 37 calls made from Flight 93 are documented on the website for the Flight 93 National Memorial. The 9/11 Museum in New York City also includes heartbreaking recordings of calls in its "In Memoriam" exhibit. A call by Brian Sweeney on United Airlines Flight 175, which crashed into the south tower, to his wife, Julie, was released through a YouTube video by the museum.

The calls made by the terrified but brave passengers and crew provide jarring insight into the emotions felt by those trapped in the planes as well as the alarming details of what was happening before their eyes.

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9/11 MEMORIAL

Several phone calls of victims trapped on one of the four hijacked planes on 9/11 have been made public. (Gary Hershorn / Getty Images / File)

Below are details of a few of the many phone calls made from the hijacked planes on 9/11, including transcripts and details released from the recipients during FBI interviews from the Flight 93 National Memorial Website.

  1. CeeCee Lyles' call to her husband, Lorne
  2. Tom Burnett's call to his wife, Deena
  3. Sandy Bradshaw's call to the Speed Dial Fix number
  4. Mark Bingham's call to his aunt and mother
  5. Jeremy Glick's call to his mother-in-law and his wife, Lyzbeth
  6. Lauren Grandcolas' call to her husband, Jack
  7. Todd Beamer's call to GTE Airfone operators
  8. Linda Gronlund's call to her sister
  9. Marion Britton's call to friend Fred Fuimano
  10. Edward Felt's call to 911
  11. Brian Sweeney's call to his wife, Julie

1. CeeCee Lyles' call to her husband, Lorne

CeeCee Lyles was a flight attendant on Flight 93. She called her husband, Lorne, from the flight at 9:47 a.m. and left a message. 

"Hi, Baby. I’m … Baby, you have to listen to me carefully. I’m on a plane that’s been hijacked. I’m on the plane. I’m calling from the plane. I want to tell you I love you. Please tell my children that I love them very much and I’m so sorry, babe. Umm, I don’t know what to say. There’s three guys. They’ve hijacked the plane. I’m trying to be calm. We’re turned around, and I’ve heard that there’s planes that’s been, been flown into the World Trade Center. I hope to be able to see your face again, baby. I love you. Goodbye," the transcript of the message reads.

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A memorial for a flight attendant called Ceecee Lyles

CeeCee Lyles was a flight attendant on Flight 93 who made calls to her husband when the plane was hijacked. (Jeffrey Greenberg / Universal Images Group via Getty Images)

She called her husband again at 9:58 a.m. on her cellphone. The FBI interview with her husband revealed information about their interaction on the phone.

"Babe, my plane is being hijacked. My plane is being hijacked. Babe, they are forcing their way into the cockpit. They forced their way into the cockpit. Babe, I called to tell you I love you, tell the kids that I love them. Oh Lord, it feels like the plane is going down."

After these words, Lorne reported that he heard screaming in the background and, soon after, the call disconnected.

2. Tom Burnett's call to his wife, Deena

Tom Burnett was a passenger on Flight 93. He made a call to his wife, Deena, and spoke to her for 28 seconds at 9:30 a.m. According to an FBI interview with Deena, she informed her husband that two planes had flown in the World Trade Center. Seven minutes later, he spoke to his wife again.

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The Twin Towers

The World Trade Center's Twin Towers were each hit with hijacked passenger planes on the morning of Sept. 11, 2001. (Albert L. Ortega / WireImage)

"The passenger that had been knifed had died," reads a quote from the FBI interview with Deena. "He told her ‘they’ were in the cockpit. She asked her husband to sit still. Thomas Burnett asked his wife, who previously worked in the airline industry, what was the probability of a bomb being on board the plane. Deena did not respond and Thomas Burnett stated he did not think they had a bomb because he did not see one; only knives."

3. Sandy Bradshaw's call to the Speed Dial Fix number

Sandy Bradshaw was a flight attendant on Flight 93. Her phone call was to the Speed Dial Fix number at the United Airlines maintenance facility in San Francisco. This line is typically used for reporting any mechanical and systems problems, troubleshooting and requesting maintenance. She alerted those on the other line that there were hijackers on the flight, that they talked about a bomb, took out a knife and killed a flight attendant.

Bradshaw also called her husband, Phil, from the flight.

4. Mark Bingham's call to his aunt and mother

Mark Bingham made a call at 9:36 a.m. from Flight 93. He called his aunt's house, where his mother, Alice Hoagland, was living. The initial call only lasted five seconds. A second call was placed about a minute later, and he was able to speak to a family friend, his aunt and his mother. Bingham's aunt and mother were interviewed by the FBI about the call and the following information was recorded.

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The Pentagon 9/11 Memorial

There are several 9/11 memorials throughout the United States, including one at the Pentagon, where one of the hijacked planes crashed. (AP Photo / Alex Brandon)

"When she [the Aunt] answered the phone, the caller was Bingham. Bingham said, ‘This is Mark. I just want to tell you I’m on a plane and it’s being hijacked.’ [The Aunt] then got a piece of paper and asked Bingham what flight he was on. Bingham replied, ‘United Flight 93’… When [Hoagland] got on the phone [Bingham] said… ‘This is Mark Bingham.’ (he stated both his first and last names) followed by, ‘I want to let you know I love you. I love you all… I’m on a flight from Newark to San Francisco and there are three guys who have taken over the plane, and they say they have a bomb. I’m calling you from the air phone.’ [Hoagland] then asked, ‘Who are they, Mark?’ [Bingham] was distracted and did not answer. [Hoagland] was not sure if [Bingham] had heard the question. There was an interruption for approximately five seconds. Bingham then stated to his mother, ‘You’ve got to believe me. It’s true.’ [Hoagland] responded, ‘I do believe you, Mark. Who are they?’ There was another approximate five-second pause, similar to the first, wherein [Hoagland] heard activity and voices in the background. People were murmuring. There were no screams. [Hoagland] got the impression that [Bingham] was distracted because someone was speaking to him. Then the phone went dead."

The call between Bingham and his family lasted two minutes and 46 seconds.

5. Jeremy Glick's call to his mother-in-law and his wife, Lyzbeth

Flight 93 passenger Jeremy Glick called his mother-in-law's house, where his wife was, from the hijacked flight. The FBI interviewed Glick's family and was able to gather the following information.

"Jeremy initially spoke [to his mother-in-law, [Joanne Makely], and immediately asked to speak to his wife, Lyzbeth. After giving the telephone to Lyzbeth, [Makely] contacted 911 via her cellular telephone. Jeremy first told Lyzbeth, that he loved her and then said that Flight #93 had been hijacked by three ‘Iranian-looking’ males, with dark skin and bandanas (ethnic types opposed to hippie type) on their heads. One of the males stated that he was in possession of a bomb in a red box and one was armed with a knife… Jeremy advised Lyzbeth that the hijackers had herded the passengers into the rear of the plane and told them… that they were going to blow-up the plane… The three hijackers then entered the cockpit of the plane… Jeremy advised Lyzbeth that he and four other male passengers were contemplating ‘rushing’ the hijackers and asked Lyzbeth if that was okay with her. Lyzbeth told Jeremy that she did not know if that was okay and asked Jeremy if any of the hijackers had guns, to which Jeremy replied they did not. In a joking manner, as if [to] ease Lyzbeth’s concern, Jeremy advised that he and approximately four other male passengers were ‘going to get the butter knives.' Jeremy then, seriously, told Lyzbeth that he and the other males were organizing to ‘rush’ the hijackers. Jeremy told Lyzbeth that he loved her and asked her not to hang up the telephone."

6. Lauren Grandcolas' call to her husband, Jack

Lauren Grandcolas called her husband, Jack, at 9:39 a.m. from Flight 93. He did not get to the phone, so she left her husband a message. The message has not been publicly released, but it was listened to by the FBI during their interview with Jack. After listening to her message, the FBI noted that Grandcolas sounded calm and reassuring while sharing that there were problems on the flight. She told her husband that she loved him multiple times and also asked him to relay to her family that she loved them as well.

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7. Todd Beamer's call to GTE Airfone operators

Todd Beamer was a passenger on Flight 93 who made a call to GTE Airfone operators at 9:43 a.m. He also made prior calls to AT&T as well as to his wife, but both calls did not go through. The call to GTE Airfone operators provided the following information, according to the 9/11 Comission Report.

"The flight had been hijacked, and the captain and first officer were lying on the floor of the first-class cabin and were injured or possibly dead. One of the hijackers had a red belt with a bomb strapped to his waist. Two of the hijackers, who had knives, entered the cockpit and closed the door behind them. At some point the hijackers closed the curtain between first class and coach so that passengers could not see into first class; those in the rear of the plane were not being monitored by the hijackers. The plane was going up and down and had turned or changed direction. He and some other passengers were planning something and he was going to put the phone down."

The phone operators that Beamer was in contact with were also interviewed by the FBI. This interview uncovered further details of a plan to fight back against the hijackers.

"Beamer asked if he could be connected with his wife, or if that was not possible, if a message could be passed to his wife telling her that he loved her. The second GTE/Airfone operator said she could hear ‘screams, prayers, exclamations, and talk of subduing the hijackers…' At approximately 9 am CST (10 am EST), Beamer said that the passengers were about to attack the hijackers."

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Collapsed Twin Towers up in smoke

Smoke envelopes the World Trade Center on Sept. 11, 2001. (James Keivom / NY Daily News Archive via Getty Images)

8. Linda Gronlund's call to her sister

Linda Gronlund was a passenger on Flight 93 and made a call to her sister at 9:46 a.m. A transcript of the devastating message she left to her loved one has been released through FBI trial evidence.

"It’s Lynn. Um. I only have a minute. I’m on United 93 and it’s been hijacked, uh, by terrorists who say they have a bomb. Apparently, they, uh, flown a couple of planes into the World Trade Center already and it looks like they’re going to take this one down as well. Mostly, I just wanted to say I love you… and…  I’m going to miss you… and… and please give my love to Mom and Dad, and (sigh) mostly, I just love you and I just wanted to tell you that. I don’t know if I’m going to get the chance to tell you that again or not. (sigh) Um… (unintelligible) All my stuff is in the safe. The uh, the safe is in my closet in my bedroom. The combination is: You push C for clear and then 0-9-1-3 and then, uh, and then it should… and maybe pound and then it should unlock. (sigh) I love you and I hope that I can talk to you soon. Bye."

9. Marion Britton's call to friend Fred Fuimano

Marion Britton called her friend, Fred Fuimano, from Flight 93 at 9:49 a.m. FBI agents interviewed Fuimano about the details of the call.

"Britton said her plane was hijacked and to take down the phone number. [Fuimano] told her not to worry because they would probably just take her to some other country. Britton said the hijackers had cut two passengers throats. [Fuimano said] that two planes had crashed into the World Trade Center, and Britton responded that she knew. Britton said they were turning and going to crash. [Fuimano] then heard a lot of screaming and then the phone went dead."

10. Edward Felt's call to 911

Edward Felt was a passenger on Flight 93 and used his cellphone to call 911 at 9:58 a.m. A transcript was obtained by the FBI of the call between Felt and the operators.

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Flight 93 National Memorial in Shanksville, Pennsylvania

The Flight 93 Memorial honors those who died on United Airlines Flight 93 on 9/11. It is located in Shanksville, Pennsylvania. (Jeff Swensen / Getty Images)

Caller: "Highjacking in pro—"

911: "Excuse me? Hey, somebody’s reporting a—"

Caller: "Highjacking in progress."

911: "Sir, I’m losing you. Where are you at?"

Caller: "United Flight 93."

911: "Wait a minute, wait, United — night flight — United flight. United Flight 93."

Caller: "Hijacking in progress!"

911: "OK, where you at up? Where are you at up?"

Caller: "I’m in the bathroom, United Flight 93."

911: "Okay, where are you at?"

Caller: "I don’t know."

911: "Where are you at?"

Caller: "I don’t know where the plane is."

911: "Where did you take off at?"

Caller: "Newark to San Francisco."

911: "Newark to San Francisco."

Caller: "United Flight 93."

911: "I got it, OK stay on the phone with me, sir."

Caller: "I’m trying to (unintelligible) at the bathroom. I don’t know what’s going on."

911: "Hey, somebody get the FAA, Newark to San Francisco, and they got a hijacking in progress. OK, yeah. Dude, get somebody from the airport on the line. This is a hijacking in progress. Are you still there sir?"

Caller: "Yes, I am."

911: "What’s your name, sir?"

Caller: "Edward Felt."

911: "Edward Felt? What’s your phone number, sir?"

Caller: [Phone number redacted]

911: "Go ahead."

Caller: [Phone number redacted]

911: Go ahead

Caller: [Phone number redacted]

911: "How big of a plane, sir?"

Caller: "It’s like a seven-fifty-seven (757)."

911: "This is a seven-fifty-seven (757). Hey, we need … it’s a seven-fifty-seven (757). Sir, sir?"

Caller: "Yes."

911: "OK, how many peoples on the plane?"

Caller: "It was — it was pretty empty, maybe (unintelligible)."

911: "Can you still hear me, sir? Sir, sir, can you still hear me? It’s over (unintelligible). There’s a plane … said the plane’s going down. It’s over Mt. Pleasant Township somewhere. Sir? It’s going down. You better make an announcement on (unintelligible). It’s over Mt. Pleasant somewhere. Hello?" (call terminated)

11. Brian Sweeney's call to his wife, Julie

Brian Sweeney was on United Flight 175 and called his wife, Julie, from the plane. His message is one of the those recorded and shared in the "In Memoriam" exhibit in the 9/11 Museum in New York City. The call was also shared through a YouTube video on the 9/11 Memorial & Museum's page.

"Jules, this is Brian. Listen, I’m on an airplane that’s been hijacked. If things don’t go well, and it’s not looking good, I just want you to know I absolutely love you. I want you to do good, go have good times, same to my parents and everybody, and I just totally love you. And I’ll see you when you get there. Bye, babe. I hope I call you."