In 1950, at an American airfield in Korea, Capt. Jim Herlihy lands his flak-damaged F-80 late at night, then orders immediate repairs. Although chief mechanic Sgt. Chuck Brennan reminds him that turning on work lights will attract enemy bombers, Jim, unwilling to wait until dawn, claims he must get to Tokyo. Presuming that Jim has a "hot date," Chuck grudgingly orders lights turned on and his men to proceed. Soon, bombing commences, killing a mechanic, and continues after Jim flies away. In California six years later, Chuck is line chief mechanic at Castle Air Force Base and eligible for retirement. The day before his vacation, he learns that Jim, whom he still resents, is now a colonel and has been assigned to be his new commanding officer. The next day, Chuck takes his wife Edith and daughter Lois to San Francisco, where his retired Air Force friend Bud Slater and wife Sylvia live in upper middle-class comfort, paid for by the lucrative job in the aircraft industry he now holds. Bud offers Chuck an executive level position at his firm, but, to Lois' disappointment, Chuck refuses, saying that he is proud of what he has achieved in the Air Force. The following week, Chuck wins four thousand dollars in a television quiz show and buys Lois a yellow convertible. To his surprise, Lois is still dissatisfied and explains that she wants him to take the civilian job, because it will give him more respect. Realizing that Lois is ashamed of him, Chuck asks Jim for his discharge. Although Jim believes Chuck's decision to leave has to do with him, he cannot comprehend the reason. Despite the antagonism he senses, Jim feels he needs Chuck's expertise to succeed. Trying to persuade Chuck to stay, Jim confides that the base has been chosen to test and implement the newest airplane, the B-52. Although he is intrigued, Chuck feigns disinterest. Eventually, Jim convinces Chuck to attend the B-52 flight school, so that he can prepare the crew for the changeover before he retires. Later, while driving the flashy convertible, Chuck and Lois, who is pleased that her father is leaving the military, encounter Jim, who is experiencing car trouble. To Chuck's dismay, Jim is instantly attracted to Lois. For several weeks, Chuck attends classes at the Boeing Company in Seattle. When he returns, he learns that Lois has been dating Jim. Confronting Jim, Chuck asks that his discharge be finalized within two months and, off the record, tells him to stay away from Lois. During a test flight, the B-52's landing gears fail to descend, but Chuck is onboard and able to fix the problem, allowing the crew to land safely. On the ground, the base commandant, having heard that Chuck disapproves of Jim dating Lois, orders the colonel to do whatever is necessary to keep the mechanic on staff. By offering to stop seeing Lois, Jim convinces Chuck to postpone his departure. When Jim stops calling her, Lois senses Chuck's relief and, to her misery, sees Jim with another woman at a restaurant. One evening, she and Chuck have a major quarrel, during which she accuses him of snubbing Jim's "important" job. Chuck tries to explain how his own job is important, but is interrupted by a telephone call, ordering him to the base. After Chuck leaves, Edith comforts Lois by saying they will resolve the problem in the morning. At the base, Chuck, Jim and other crewmen are told that they will be conducting a top-secret flight to Africa to test the B-52. Forbidden to call home, the airmen take off, flying through storms, and after a mid-air refueling over Bermuda, proceed eastward, over the Egyptian pyramids, Algiers and Africa, where they turn around. During the last part of the return trip, Chuck discovers that a control panel has short-circuited, causing a fire and Jim orders everyone to evacuate. Hoping to get the plane home, Jim warns Castle airbase of a possible crash-landing, then discovers that Chuck has remained onboard and insists on staying with him. To avoid argument, Jim triggers Chuck's ejector seat, sending him catapulting out of the smoking plane. After landing the plane, Jim sends out rescue patrols to round up all crewmen. Everyone is found, except Chuck, whom Jim fears landed in rough canyon territory. After searching for several hours, Jim notices a flash spot on an area photograph taken by a rescue worker. Although others believe the spot is a halation, Jim, hoping it is a mirror signal, flies out to investigate personally. After a long search, Jim sees a flash or reflection of light, and orders the helicopter down to a flat spot in a canyon. Because of approaching fog, he orders his pilot to leave him and return after the fog dissipates. He then climbs down the canyon alone. Following a tapping sound, Jim eventually finds Chuck, who, though severely injured, has signaled by hitting metal on rock. Chuck confesses that Jim is the last person he expected to come to his rescue. After accusing him of being "out for himself," Chuck reminds him that a mechanic was "shot up" in Korea so that Jim could keep his "hot date in Tokyo." Appalled by Chuck's misconception, Jim explains that, to prevent the interception of a radio transmission by the enemy, he was ordered to fly to Tokyo and report to his superiors that an important secret base had been discovered by North Koreans and was in imminent danger. Later at the hospital, Chuck, who has been nominated for a commendation, informs his superiors that he may have the solution to prevent future electrical problems in the control panel. Ashamed to face Lois, he asks the understanding Jim to explain to her why he felt he was doing the right thing. After searching her own heart during Chuck's ordeal, Lois now appreciates what her father has achieved. Through the hospital window, Chuck watches as the couple reunites. When he is told that his discharge papers are ready, Chuck says that he is too young to retire.
