Humans can survive for weeks without food; days without water; however, we can only survive for minutes without oxygen. While the percentage of oxygen in the atmosphere remains fairly constant up to 70,000 feet, the available amount of oxygen to sustain mental and physical alertness decreases above 10,000 feet. The atmosphere is primarily nitrogen (78%) with oxygen comprising 20.9 percent of the atmosphere.
The atmosphere is generally considered to exist up to 100,000 feet (above this altitude the atmosphere is virtually a vacuum until reaching outer space). One-half of the atmosphere is contained from 18,000 feet to the earth's surface (the other 50 percent is from 18,000 feet to 100,000 feet). At sea level, the pressure of the atmosphere is 14.7 pounds per square inch (psi). At 18,000 feet the pressure is 7.34 psi. By 34,000 feet, the pressure is reduced to one-half the value at the 18,000 foot level (3.62 psi). It is this reduction in pressure (or in other words, the less dense air) that causes hypoxia.
Hypoxia is the effects of an insufficient supply of oxygen to the body. Every person can have different symptoms when suffering from hypoxia (U.S. Air Force aircrews are required to take an altitude chamber ride every three years to reinforce and identify their hypoxic symptoms). Some of the common symptoms are: lightheaded sensation, dizziness, reduced vision, and euphoria.
Tuesday, September 25, 2012
For Those Who Still Can't Believe What The Madman Said ...
RACHEL HAS THE VIDEO! Yes, it's true, this imbecile is SO IGNORANT of BASIC aerospace science that he would presume to make decisions about the FAA (that's Federal Aviation Administration) and is a twitchy finger away from the proverbial nuclear button. As President Obama said, "If Mr. Romney wants to start another war, he should say so." On the other hand, Mitt knows ALL ABOUT interplanetary travel to the planet Kolob on the wings of WHITE Mormonic harp-playing angels ... By the way, Mitt, there's very little oxygen at a passenger plane's cruising altitude of 30,000 feet; and NO ONE says "aircraft" — it's "PLANE" to the rest of us with knowledge of BASIC science. Here's a brief primer, you fucking MORON:
Posted by Carlos at Tuesday, September 25, 2012