A former chief of the Australian Navy is under fire for taking his girlfriend for a ride on a military submarine and proposing to her.

Vice Admiral Michael Noonan used his position to grant his partner Samantha Heighway approval to board the HMAS Waller on June 23 last year, News Corps reports.

The submarine was at sea to film material for Defence Force Recruiting near Geraldton in Western Australia at the time.

The Defence Department has said no rules were broken but it was “not routine” as civilians were not commonly invited on such trips.

Coalition assistant defence spokesman Phil Thompson told News Corp the incident was an “abuse of power”.

“The Navy is a professional outfit, this isn’t the chief of Navy’s personal love sub,” he said.

“There are proper times when civilians can go on military equipment or bases, but this circumstance is not one of them in my opinion.”

Mr Noonan retired from Defence in September last year.