[Skip to Content]
[Skip to Content Landing]
May 5, 1989

High-Altitude Flights and Risk of Cardiac Disease

JAMA. 1989;261(17):2504. doi:10.1001/jama.1989.03420170046025

To the Editor.—  The last issue for 1988 contains a question about high-altitude flights and the risk of cardiac stress. Much of Dr Cummins'1 answer is correct, but there is also an important misstatement. The federal aviation regulations in effect require that no transport aircraft may operate with a cabin altitude that exceeds the equivalent of 8000 ft above sea level. As Dr Cummins states, weather and traffic conditions may oblige the pilot to fly at the maximum operational limit of the aircraft, but passengers may normally expect to be at a cabin altitude of 8000 ft under those circumstances.The figures used for the two aircraft in question are correct. However, several other very popular jet airliners are built with somewhat lower pressurization schedules. That is, an aircraft at 35 000 ft may have a much higher cabin altitude than the 5500 ft he quotes, but in no