Efforts to reduce weight to make the aircraft suitable for carrier operations had led to the deletion of ejection seats during the design process for the Skywarrior, based on the assumption that most flights would be at high altitude. A similar arrangement with an escape tunnel had been used on the F3D Skyknight. Aircrews began joking morbidly that "A3D" stood for "All Three Dead". (In 1973, the widow of a Skywarrior crewman killed over Vietnam sued the McDonnell Douglas Aircraft Company for not providing ejection seats in the A-3.) In contrast, the US Air Force's B-66 Destroyer, not subject to the weight requirements for carrier operations, was equipped with ejection seats throughout its service life.