Stresses of Flight Modern commercial aircraft are very safe and, in most cases, reasonably comfortable. However, all flights, short and long haul, impose stresses on all passengers. Preflight, these include airport tumult (e.g., carrying baggage, walking long distances, and flight delays). Inflight stresses include lowered barometric and oxygen pressure, noise and vibration (including turbulence), cigarette smoking (banned on most airlines today), erratic temperatures, low humidity, jet lag, and cramped seating. Nevertheless, healthy passengers endure these stresses which, for the most part, are quickly forgotten once the destination is reached. In general, passengers with stable medical conditions usually arrive at the destination airport none the worse. However, there is always the potential that some passengers, particularly those with unstable illness, may become ill during or postflight due to these stresses. A brief review of these stresses follows.