Despite a popular urban myth, airline captains generally do not have the legal authority to officiate a marriage mid-flight. A pilot's legal authority is strictly limited to the safety and operational aspects of the aircraft and the well-being of the passengers and crew; it does not extend to civil or religious legal ceremonies. Most jurisdictions require a wedding to be officiated by a judge, a religious official, or a state-sanctioned official with specific credentials. While ship captains on certain cruise lines (like Royal Caribbean) can perform legal ceremonies in international waters under specific laws (such as Bahamian Law), this is an exception and not the rule for aviation. If you wish to have a "wedding in the sky," you would typically need to bring a legally authorized officiant on board as a passenger and perform the ceremony, though many airlines discourage this for safety reasons. Most "airplane weddings" are purely symbolic.