Wheel-well stowaways are individuals who attempt to travel in the landing gear compartment, also known as the wheel bay or undercarriage of an aircraft. Between 1947 and June 2015, a U.S. Federal Aviation Administration (FAA) researcher had documented 113 such attempts on 101 flights. These 113 people were all male and predominantly under age 30.^[1] There were 86 deaths, a 76 percent fatality rate,^[2] with many unidentified decedents. There may be additional undocumented cases of wheel-well stowaways.^[3] A further 19 incidents, identified since 2015, are listed here.

Wheel-well stowaways face considerable risk of death during all phases of flight. Some have been unable to remain in the well during takeoff and landing and have fallen to their death. Immediately after takeoff, the landing gear retracts into the wheel wells, with the potential to crush the stowaway.^[4] If the stowaway is able to avoid physical injury, they still face hypothermia and hypoxia risks at the extremely low temperatures and low atmospheric pressure at high altitude, as well as hearing damage from prolonged exposure to the dangerously high noise levels outside the cabin.

At altitudes above approximately 2,500 m (8,000 ft), hypothermia becomes a risk and reduced atmospheric pressure and partial pressure of oxygen, which drop below the level required to support brain consciousness at the cruising altitudes of jet aircraft, may impair physiological processes.^[5] At altitudes above 6,000 m (20,000 ft), stowaways may also develop decompression sickness and nitrogen gas embolism.^[5]

Temperatures continue to decrease with altitude, and may drop as low as −63 °C (−81 °F).^[5] As the plane descends to lower altitudes, a gradual rewarming and reoxygenation occur;^[5] if the stowaway does not regain consciousness and mobility by the time the landing gear is lowered during the final approach, or has already died, the body may fall from the aircraft.^[2] According to the FAA, it is likely that the number of stowaways is higher than records show because bodies have fallen into the ocean or in remote areas.^[6][3] Many wheel-well stowaways are found, dead or alive, with their bodies covered in frost, suggesting severe hypothermia during flight. Fidel Maruhi, who survived a wheel-well flight from Tahiti to Los Angeles in 2000, had a body temperature of 26 °C (79 °F), well below the level usually considered fatal, when emergency personnel began treating him on the runway.^[7]

It is unknown how survivors did not perish from such extreme conditions. A 1996 FAA paper proposed that humans, when placed in an environment that overwhelms the body's ability to control its own temperature, become poikilothermic and enters a state of hibernation that allows the body to temporarily survive in low-oxygen environments.^[3] Among 99 known cases of wheel-well stowaways from 1947 through June 6, 2013, there were 76 fatalities and 23 survivors.^[8] It is possible there are additional undocumented cases of successful surviving wheel-well stowaways escaping the aircraft undetected possibly with outside assistance.^[3]

One survivor, Armando Socarras Ramirez, who defected from Cuba aboard an Iberia flight from Havana to Madrid in 1969, recalled in 2021 that his earliest post-flight memories are of Spanish doctors calling him "Mr. Popsicle" because ice covered his body when the pilot discovered him after his arrival. He had boarded the plane while it was taxiing, carrying a flashlight, rope, and wool to stuff his ears; a companion fell out of the other wheel well before takeoff and a third backed out at the last moment. After takeoff, he had suffered frostbite on his middle finger so severe it turned black holding on until the wheels retracted, but then remembered nothing save shivering and shaking from the extreme cold until he lost consciousness. It took him a month in a Spanish hospital to regain his hearing, but he reports no lingering medical issues from the experience.^[1]

Wheel-well stowaways have been widely covered in the press and media at large throughout the history of passenger airlines. One of the most notable incidents involved Keith Sapsford (14) from Sydney, Australia, who fell 200 feet (60 m) to his death from the wheel-well of a Tokyo-bound Japan Air Lines Douglas DC-8 on February 24, 1970, shortly after takeoff from Sydney Kingsford Smith Airport. Amateur photographer John Gilpin was testing his new camera lens by taking pictures of planes taking off that day, and did not realize he had captured the boy's final moments until he developed the pictures a week later. The photo was then featured in Life magazine's issue for the week of March 6, 1970, in their "Parting Shots" section of particularly newsworthy photos, across the fold of a two-page spread.^{[9][10][11][12][13][14]}

Below is a chronological list of documented aircraft wheel-well stowaway incidents. Stowaways have also traveled in a cargo hold,^[15] or in a spare parts compartment,^[16] both of which are pressurized, or even in the pressurized cabin itself.^[17] In at least one other instance, on July 31, 2013, a cat survived a flight from Athens to Zürich in the front undercarriage of an Airbus A321.^[18] Those types of incidents are not included in the scope of the list below.