U.S. Lt. Gen. Marc Sasseville is retiring from the Air Force after four decades.
NEW YORK -- Twenty-three years ago, F-16 fighter pilot Marc Sasseville was sent on a mission that he thought could be his last.
Two hijacked planes had flown into the World Trade Center's twin towers in New York City, and a third had struck the Pentagon. Sasseville received orders on Sept. 11, 2001 to prevent another hijacked airliner headed for Washington from reaching its target. That plane was United Airlines Flight 93, which had been hijacked by four al-Qaida terrorists and ultimately crashed in Shanksville, Pennsylvania.
In an ABC News exclusive interview, Chief Global Affairs Correspondent Martha Raddatz spoke with Sasseville about the heroic operation he took on alongside fellow F-16 pilot Heather Penney, who was just 26 years old at the time.
They both took off from Joint Base Andrews near Washington, D.C., not yet knowing what their mission was.
"One of the memories that will stay with me forever is seeing the Pentagon on fire and being able to smell the fumes that were coming off of that," Sasseville said. "The burning concrete, the fuel from the airplane that it hit."
Sasseville added that the "event and everything that's happened since, has been a motivating imperative for me that we need to be able to continue to look forward and be prepared for future challenges."
He told Raddatz that after seeing the destruction, he immediately thought about Dec. 7, 1941, when Japan attacked Pearl Harbor.
"Here we go again," he said. "We just got attacked again and we are really challenged to respond."
Eventually, Sasseville and Penney received the chilling orders to locate Flight 93.
Because they had scrambled their jets so quickly, their fighters were not armed with missiles.
"My challenge was, how do we take down this very unique threat, a civilian airliner ... full of people, full of civilian people?" Sasseville recalled.
Together, Penney and Sasseville decided that if required, they would ram the hijacked plane with their fighter jets - a suicide mission.
"The training kicked in," Sasseville said of his decision. "I felt like I was on autopilot."
Sasseville would target the front of the jetliner and Penney would target the tail section.
At home, Sasseville had a wife and two young children, aged five and three, who were unaware of his mission - including being prepared to give his own life to save others.
"It's a testament to Sass' leadership that he didn't ask anyone else to lead that mission," Penney told Raddatz of his choice to intercept the hijacked plane. "He wouldn't ask anyone else to give what he was unwilling to give."
Sasseville and Penney would later learn that the passengers and crew on Flight 93 stormed the cockpit and fought back against the terrorists. They regained control of the plane before it crashed in an empty field in Shanksville, killing everyone on board.
"If those heroes on 93 - and by the way, those are the real heroes - if they hadn't taken action and they hadn't done what needed to be done, it would have been a very different outcome for me and my family," Sasseville said.
After both pilots landed their aircraft at Joint Base Andrews for refueling, they took off again - this time on a combat air patrol mission above the nation's capital. They did not know at the time that they were about to escort Air Force One as President George W. Bush returned to Washington. Photos taken at the time by the press corps accompanying Bush show Sasseville's F-16 flying off the presidential jet's left wing.
When he returned home to his wife, Karin, and their children, Sasseville kept quiet about his role on 9/11. He hugged his family tightly, told them that he loved them and said that he would be away at work "for a long time because something very bad had happened to America."
Karin later learned the story about her husband's actions that day. Sasseville said that she was in awe of him, and proud.
Sasseville remained in the Air Force after 9/11, ultimately becoming a three-star general and the number-two officer in the National Guard.
Now, after 40 years of service to his country, U.S. Air Force Lt. Gen. Sasseville retired from the Air Force on Wednesday. He took his final flight on an F-16 on May 15 out of Joint Base Andrews, the same base from which he and Penney departed on Sept. 11, 2001, with orders to find Flight 93 and to destroy it as it made its way to D.C.
The unarmed F-16 jet that Sasseville flew on Sept. 11, 2001 has been reconfigured by the Air Force - ironically, to serve as a target drone for pilots in training to shoot down for practice.
Karin and their children were there for Sasseville's retirement ceremony.
"It has been a tremendous honor and a privilege to serve, and a truly rare opportunity for me and my family to make a difference," Sasseville said during his speech. "Now, you have the watch. Thank you all."
To kick off his retirement, Sasseville and his family are traveling to Puerto Rico, taking some much-deserved time off to rest and relax.
"I'm going to learn how to play golf again," he said, adding that he also plans to rediscover who he is now and "get back to a normal life."
----------
* Get Eyewitness News Delivered
* Download the abc7NY app for breaking news alerts
Have a breaking news tip or an idea for a story we should cover? Send it to Eyewitness News using the form below. If attaching a video or photo, terms of use apply.