Ryan Lochte knows how to make a girl feel special ... dropping $700 for a private helicopter ride to pop the question on the top of a mountain.
Lochte proposed to his Playboy model girlfriend Kayla Rae Reid on Sunday, and judging by the video ... he went all out. Kayla said it was her first time in a chopper, and clearly Ryan made it memorable -- even if she knew what was coming.
Sources close to the situation tell TMZ ... Lochte booked his romantic flight through Orbic Air in Burbank. He got the Mountain Top Landing package ... which included a ride to a Malibu peak and a 30 minute stop for some celebratory champagne, strawberries and cheesecake.
We're told he also had a photog on board to capture the memories.