Matthew Perry's Ex Says They Joined the Mile-High Club on Bruce Willis' Plane

Matthew Perry and his ex, René Ashton, once got freaky aboard Bruce Willis' private plane ... at least that's what she's hinting at.

René implied that she joined the mile-high club when she and Matthew were jetting off to Turks and Caicos with Bruce and his girlfriend at the time.

In the new 3-part Netflix doc, "The One About Matthew Perry," the actress said the invite came before the late "Friends" star went to shoot "The Whole Nine Yards."

She said Matthew was "so excited," recalling ... "He's like, 'Bruce wants us to go on his private plane. Bruce wants me to share a plane with him.'"

At one point, a producer off-camera asked how the flight was, leading René to quip ... "I joined a club."

And once they got to Turks and Caicos, René said the trip was "pretty amazing" and paparazzi-free, so they got to have a normal experience and enjoy their time.