This week’s New England Journal of Medicine published a study funded by Boeing which has received much media attention, including this Washington Post article.
The study sought to reveal the effects on passengers of different cabin pressures during prolonged flights. The authors hoped to find whether different pressures made passengers uncomfortable or caused acute mountain sickness, an illness marked by headache, shortness of breath and nausea which is caused by rapid altitude gain. Typically airplane cabins are pressurized to a pressure equivalent to an altitude of 8,000 feet, since maintaining normal atmospheric pressure during a flight would require much more fuel and would increase wear on the airframe.
The study placed volunteers in a hypobaric chamber to simulate a 20 hour flight. Simulated flights were conducted with the chamber pressurized to different altitudes and the patients were monitored for adverse events. They also completed a questionnaire about their symptoms. For the sake of realism, I hope they underwent a prolonged and detailed security screening and had their deodorant summarily confiscated.
The good news is that no one developed acute mountain sickness. Passenger discomfort, however, increased with decreasing pressure. There was less discomfort when the cabin was pressurized at 6,000 feet than 8,000 feet. Since Boeing sponsored this study, I assume they’re about to announce sales of an airframe that remains pressurized to 6,000 feet, heralding a new era of travel comfort.
At least now I know why I was uncomfortable during our family’s recent flight to Orlando. Until this week I thought it was because the food was horrible and my three year-old wouldn’t stop hitting me.