Tom Cruise is back as Pete 'Maverick' Mitchell in the movie but Kelly will not return to Top Gun 2.
The 60-year-old actress won hearts playing Charlie Blackwood in the 1986 original - and previously said she'd love to return.
But Kelly has not travelled to the film set in San Diego, California along with her former cast mates.
Instead, she spent her weekend volunteering at the First Congregational Church, near her rural home in Hendersonville, North Carolina.
In an interview with ET the 62-year-old actress - who diagnosed with alpha one antitrypsin disorder about five years ago - was unusually candid about why she was not asked to co-star with Tom Cruise in the Top Gun sequel titled Maverick.
'I'm old and I'm fat and I look age-appropriate for what my age is, and that is not what that whole scene is about,' said the star who played Charlie Blackwood, Maverick's instructor, in the 1986 hit film. 'But ... I'd much rather feel absolutely secure in my skin and who and what I am at my age as opposed to placing a value on all that other stuff.'
Kelly Mcgillis before and after photos