'Apollo 13' turns 30: How NASA legend Gerry Griffin helped director Ron Howard 'get it right' (exclusive)

Happy 30th Birthday to "Apollo 13!"

Director Ron Howard's harrowing true tale of the unlucky Apollo 13 mission to the moon in 1970 still stands as one of the finest space survival movies of all time and a testament to the unprecedented acts of courage and ingenuity that brought three astronauts back to Earth in a damaged spacecraft. It was nominated for nine Academy Awards including Best Picture, and ultimately won Oscars for Best Sound and Best Editing.

Adapted from Jim Lovell & Jeffrey Kluger's 1994 novel "Lost Moon" and starring Tom Hanks, Ed Harris, Bill Paxton, Kevin Bacon, Gary Sinise and Kathleen Quinlan, "Apollo 13" was released in theaters on June 30, 1995. It was hailed as a tense, technically accurate, and riveting account of that imperiled lunar mission that nearly cost the lives of astronauts Jim Lovell, Fred Haise and Jack Swigert when the oxygen tank on their spacecraft's service module exploded, damaging the craft's life-support and electrical systems.

Keeping the production nominal and on track in an official advisory role was NASA living legend Gerry Griffin. The former Johnson Space Center chief and flight director for 11 manned Apollo missions was Hollywood's go-to expert on "Apollo 13's" entire shoot, and eh worked closely with cast and crew to provide guidance and authenticity to the project. He even has his own custom director's chair at home to prove it!

Who better to provide first-hand mission details than the man whose Gold Team would have been Apollo 13's landing team had things gone according to plan? We were fortunate enough to be able to connect with Griffin from his Texas home where he shared more vivid memories of working on "Apollo 13" back in 1994 and 1995.

"I started at the top," Griffin told Space.com. "When I got the call to be the technical advisor I thought, 'Gosh, I've got to do that.' Because I was in the middle of it as a flight director and thought I could bring something to it that would help. I started with Ron Howard, Tom Hanks, Bill Paxton, Kevin Bacon. I knew nothing about making movies. My view of Hollywood was all glitz and little else, but at the end of the day I quickly learned that I was wrong. It's a hard-working, goal-driven enterprise that tries to get it right. The good guys do.

"After a while though, it was kind of like NASA. Take whatever time it takes, work 12 to 15 hours a day, work the problem."

In addition to "Apollo 13," Griffin later lent his expertise to Robert Zemeckis' "Contact" and Mimi Seder's "Deep Impact."

"The way Ron [Howard] explained it to me when we started was, 'Look, I'm not making a documentary. I'm making an entertaining movie based on facts.' That was his goal. He wanted me to stay glued to his side and if I saw something that was wrong, that didn't happen that way, to tell him. He had to have license to do certain things and I know where he took them.

"It didn't affect the technical details, but he was amazing and also an extremely nice guy. He was Opie grown up! And it turns out that Bill Paxton and I went to the same high school in Forth Worth, Texas. You always find connections when you start making movies."

Regarding the dramatic crew swap-out from Ken Mattingly (Gary Sinese) to Jack Swigert (Kevin Bacon) depicted in the film after Mattingly was possibly exposed to the measles, Griffin said there definitely were some added touches of intensity tacked onto those scenes from real-life.

"I thought the switchover right before launch was kind of overdone," he notes. "It showed we had backup crews that were ready to step in throughout the whole program. To us it was just, 'Okay, next up, let's go.' But it was good and it turned out well."

On the subject of necessary alterations to scenes or small suggestions, Griffin remembers some, but in the total service of the on-screen story, nothing was too egregious. Having a tour group led by Hanks inside NASA's Vehicle Assembly Building right beside the Apollo 11 mission's Saturn V rocket while it was being stacked was a bit of a stretch to say the least, but hey, that's Hollywood.

"In that opening scene when they're in Jim Lovell’s house watching the Apollo 11 landing, that didn't happen. But Ron told me that it gives him the opportunity to introduce a bunch of characters that are going to be in this movie for the rest of the time. He can get them all introduced that night.

"There was another scene that stands out and I thought at first, 'Oh gosh, it didn't happen this way.' It's when they were working on the lithium hydroxide canisters that scrubbed the air in the cabin. The lunar module was only good for a four or five-day mission and then it was done, so it didn't have many round canisters that fit in their slots that they had to change those filters to keep the CO2 out of. The command module used square canisters and we had plenty of those so we had to figure out a way to use those. We put an engineer named Ed Smiley in charge and he got a group together and read from a list of all their onboard equipment.

"They didn't have it in their hands yet. They found the solution, went and made one like they wanted, and brought it into the Control Center. I was in there when they brought it in.

"In the movie, the way they got to the solution is the guy that played Ed walked in with this bag of stuff and dumps it on the table and says 'okay, this is what they've got'. Ron told me, 'Gerry, this is not a documentary. We're gonna get to the same solution.' And we were laughing about this and it was fine."

The Gene Kranz character that Ed Harris portrayed was actually a composite and Griffin worked one-on-one with the acclaimed actor because he wanted to be prepared and get the role right.

"There were four flight teams that worked on the Apollo 13 mission and I was one of those four," he explains. "Ron came to me earlier and side he didn't have time to develop four characters that stand alone in the phases of the mission and asked if I'd be upset with a combined character."

In actuality, Griffin recalls that Gene Kranz was taken off-line during those crucial hours of the mission so he could go figure out how to get the command module turned back on after they'd powered it down, something that hadn't ever been done in space, only plugged in while on the ground.

"He came back in and did that powering up the command module toward the end of the mission. It was fortuitous that we had four teams so we didn't have to add any manpower. My team was supposed to do the landing on the moon, of course that got bypassed pretty fast. The part that Ed played was a little more serious than Gene actually was and is still. The vest was something that started in Gemini I think, but maybe Apollo. But he wasn't presented it, he wore it into the room, and they really were made by his wife.

"When we got to a mission there were no Chief Flight Directors. There might be composite decisions and Neil Armstrong used to repeat it all the time. Mission Control and the astronauts were just the tip of the iceberg. There was huge support below us from contractors and other centers. I was told, and can't confirm it, that we were even offered help from the Soviet Union. Everybody wanted to help and it was worldwide viewers that watched this. I think that's what made the movie even more poignant, that it brought that out because there was a lot of footage from that era in there."

Griffin was also on hand to view all the daily film rushes with Howard and to speak up if he observed anything that seemed off. When he witnessed the final product all put together, he was extremely pleased.

"It was really good," he adds. "And I learned a lot about moviemaking in it, not all that I would eventually. But I know when you have people like Ron Howard and Tom Hanks and Bob Zemeckis and Jodie Foster [On "Contact"], you're ahead of the game. It's a hard-working bunch of people.

"I was very impressed with them and I'm proud of the move that came out of it. Ron did what he said what he was going to do. He wanted it technically accurate but he had to have some license to tell the story in a more entertaining way. He said he'd read the transcript of the air-to-ground communication and said that it sounded like just a normal flight to him. We weren't excited!”