Top Gun: Maverick sees him revisit brilliant but reckless pilot Pete "Maverick" Mitchell, still flying but unable to let go of his past.
The trailer shows Cruise apparently pulling off some incredible aerial moves on board a US Navy jetfighter.
"Everything you see in this film is for real," he told the San Diego audience.
"We're working with the Navy, all of the flying you see in this picture is real, I really wanted to give you all an experience of what it is to be inside that aircraft.
"To me, Top Gun is about competition, it's about family, it's about sacrifice , it's about heroism, it's about aviation.
"It's a love letter to aviation."
Released in 1986, Top Gun was apparently inspired by an article titled Top Guns published in a magazine three years earlier.
The film, directed by the late Tony Scott (Ridley Scott's brother) was widely praised for its cinematic achievements in capturing breathless action sequences. It won an Academy Award for best original song for Take My Breath Away by the band Berlin.
It made a star of Cruise and also featured Kelly McGillis, Meg Ryan, ER's Anthony Edwards and Val Kilmer - who is also back for the sequel but is not seen in the first trailer.
Its critics said the film served as a glorified jingoistic recruitment tool for the US Navy but in 2015, the US Library of Congress selected the film for preservation in the National Film Registry.
"Thirty-four years ago I made a movie in San Diego," Cruise told the Comic-Con audience following a panel to launch the latest film in the terminator franchise, starring Arnold Schwarzenegger and Linda Hamilton.
"Thirty-four years and you've been very patient with me and I felt it was my responsibility to finally really deliver for you."