“Top Gun” is undoubtedly one of the most iconic military films in history. The 1986 blockbuster film starring Tom Cruise as Navy pilot Maverick is still beloved by both those who saw it in theaters more than 30 years ago or as recently as 30 days ago.

Just ask actor Tom Skerritt, who played TOPGUN commanding officer Cmdr. Mike “Viper” Metcalf.

“Generation after generation have come to love that film and watch it with the same enthusiasm as the past ones,” Skerritt said in the Blu-Ray special edition of the film released in 2016 for the movie’s 30th anniversary. “There’s not a pilot in the world who hasn’t seen Top Gun multiple times.”

Even if you’ve seen it 20 times, there are some facts you still may not know about the film.

Call sign “Viper” came from U.S. Navy Rear Adm. Pete Pettigrew

Retired U.S. Navy Rear Adm. Pete “Viper” Pettigrew, a naval aviator and flight instructor at the U.S. Navy Fighter Weapons School that became known as TOPGUN. Pettigrew served as a technical advisor for the film and apparently provided the inspiration for the call sign “Viper” in the “Top Gun” movie.

“My claim to fame is I am actually, really the Viper…that was actually my real call sign many, many years ago,” Pettigrew said in 2017.

According to Pettigrew, two writers asked if they could use his call sign for Metcalf in the film. Although Pettigrew said he pointed out he never was the commanding officer of TOPGUN, the writers told him it didn’t matter.

Another fun fact — Pettigrew also made an appearance in the film with Kelly McGillis, who played Charlie, as her friend “Perry” after Maverick infamously sang “You’ve Lost that Loving Feeling.”

Charlie’s character was inspired by a real, badass woman

Maverick’s love interest was not originally intended to be Top Gun flight instructor Charlotte “Charlie” Blackwood. In fact, a 1985 People magazine article said that filmmakers were weighing having his love interest be a gymnast at one point. Ultimately, the idea for Charlie was solidified after filmmakers briefly met Christine Fox during a meeting at then-Naval Air Station Miramar with the air wing’s commanding admiral. Fox, who was then 30, was working as an analyst with the Center for Naval Analyses.

She told Military.com in September that Charlie’s character was only “loosely” based on her. She acknowledged she spent a day with McGillis, sharing more about her work with the actress. Furthermore, Fox went on to serve as the acting deputy secretary of defense during the Obama administration from 2013 to 2014 — earning her a title as the highest ranking woman the Pentagon has seen as of yet.

Iconic moments were ad-libbed

One of the most memorable scenes in the movie was not included in the original script. Actor Val Kilmer, who plays Lt. Tom ‘Iceman’ Kazansky, improvised his reaction coughing and saying “bullsh*t” as he cast doubt on Maverick’s description of giving the finger to enemy aircraft, according to IMDB. The other actors’ reactions to the comment are reportedly authentic.

Additionally, IMDB reported that Cruise inserted an impromptu kiss with McGillis after he forgot his line. The scene is following Charlie’s biting assessment of Maverick’s flight performance in front of his peers. She later confesses that she sees some “real genius” in his flying, however, she admits she couldn’t say that in front of others because she’s worried they’ll see she’s falling for him. Cruise forgot his response, and proceeded to kiss McGillis instead. The moment was well received by director Tony Scott that the scene was kept.

Charlie’s house still exists — and it’s getting a makeover

Charlie’s house, the one where she and Maverick had their first date, still stands in Oceanside, California. The house, a Victorian built in 1887 and originally located at 102 North Pacific Street, can be viewed at its new location as part of the Oceanside Beach Resort Property. The home was temporarily moved from its original location in 2019 as part of a nearly $1 million restoration process before finding its final destination at the resort in May 2020. The home is being restored so the public can visit it, and the resort is slated to open in 2021, according to a Visit Oceanside press release.

What happens if you quote the film at the real TOPGUN

According to former naval aviator and TOPGUN instructor Cmdr. Guy “Bus” Snodgrass, students at TOPGUN are slapped with a hefty fine of $5 if they quote the 1986 blockbuster. That’s because “you don’t turn TOPGUN into a joke by referencing the movie,” he wrote in his book “TOPGUN’s Top 10: Leadership Lessons from the Cockpit,” which was published in 2020.

Four Navy pilots were selected to fly the jets in the film

Cruise and the other actors had a little help from some tried and true Navy pilots when it came to flying the fighter jets for the film. The Navy was contacted by those working on “Top Gun” in pursuit of pilots who might fly the F-14 for the film, and among those chosen was Scott Altman, who later became a NASA astronaut, according to NASA.

“The skipper of our squadron picked four guys he thought he could trust to have this kind of carte blanche to break the rules a little bit,” Altman told CNN in 2009.

In fact, Altman is featured in some of the most prominent moments in the film, including the one where Maverick flips off the enemy.

“They said go ahead and gesture at the other airplane,” Altman told CNN. “So when you’re looking at the scene where he’s communicating with the Russian, or the bad-guy pilots in the movie, that would be my finger.”

There are real Navy ships featured in the film

Hollywood had access to several Navy vessels while filming — aircraft carriers Ranger, Enterprise and Carl Vinson. While the Vinson is still activated, the Ranger was decommissioned in 1993 and the Enterprise was decommissioned in 2017.

Ultimately, Paramount Pictures footed a bill totaling $1.8 million to use the Navy’s ships and aircraft for the film, per the Washington Post.