Martha Stewart Says She Warned JFK Jr. to Get a Copilot Before His 1999 Plane Crash

Martha Stewart says she warned John F. Kennedy Jr. that he should have a copilot before he died in a fatal 1999 plane crash with his wife, Carolyn Bessette, and her sister, Lauren.

Martha made the stunning revelation on Tuesday's episode of "The Real Housewives of New York City," telling her fellow cast member, Daisy Toye, about her discussion with JFK Jr. days before his small plane plummeted into the Atlantic Ocean off the coast of Martha's Vineyard, killing everyone on board.

At the time, JFK Jr. was a new pilot manning the controls of the plane when it flew into a dense fog, causing him to become confused and the aircraft to nose-dive and crash into the ocean.

During Tuesday's episode, Martha told Daisy that she was chatting with JFK Jr. days before the fatal crash ... after he called her for advice about his magazine, "George."

During their convo, Martha said they also discussed JFK Jr.'s plans for the weekend, and he said he was going to fly around with Carolyn and her sister in a jet. According to Martha, that's when she recommended JFK Jr. he use a copilot for the trip -- something that John totally dismissed.

Martha told Daisy that over the years she's thought about that conversation so many times and that she feels "sorry" for what happened.

On that fateful day, July 16, 1999, JFK Jr. was flying with Carolyn and Lauren from Essex Airport in Caldwell, New Jersey to Martha’s Vineyard to drop off Lauren when tragedy struck. After dropping off Lauren, the couple was supposed to fly to Hyannis Port for John's cousin Rory Kennedy's wedding.