An official website of the United States government
Here's how you know
A .mil website belongs to an official U.S. Department of Defense organization in the United States.
A lock (lock ) or https:// means you’ve safely connected to the .mil website. Share sensitive information only on official, secure websites.

Home : News : Features : Display
NEWS | July 21, 2014

Flying ‘high’: Aircrew members undergo altitude chamber training

By Senior Airman Austin Harvill 633rd Air Base Wing Public Affairs

Aircrew Service members contend with many factors while operating in air space. Aside from enemies outside of their cockpits, the flight environment itself can be treacherous. Aircrew and pilots may endure upwards of nine times the force of gravity, dizzying maneuvers and shifting perceptions, all-the-while trying to accomplish diverse and unique missions.

Whether in the cockpit or not, such factors test the limits of the human body. Fortunately, personnel at the 633rd Aerospace Medical Squadron altitude chamber are dedicated to ensuring aircrew members understand those dangers before they take to the skies.

"Vision loss, confusion, slurred speech and the threat of passing out could happen if aircrew members' breathing systems are damaged," said U.S. Air Force Capt. Max Alvarado, 633rd AMDS aerospace physiologist. "Unfortunately, if there is a systems failure, aircrew members won't be told they are undergoing these subtle - and sometimes deadly - changes."

That's where the altitude chamber comes into play. This tool allows Alvarado and his team to show participants the potential threats of depressurization and oxygen deprivation, commonly known as hypoxia, without putting them in danger.

Hypoxia is one of the biggest threats to pilots, said Alvarado. It feels good, it happens slowly and as it becomes more severe, the victim becomes less able to identify an issue.

Like hypoxia, depressurization can also cause serious issues. Most people associate pressure regulation with the ear-popping sensation they have on airplanes. Rapid changes of pressure can cause serious damage to the entire body as gasses rapidly expanding within the body.

Because depressurization cannot be simulated without harming Service members, unlike hypoxia, Alvarado and his team conduct classroom sessions on depressurization. The effects of pressurization on the other hand can still be implemented realistically and safely, thanks to the altitude chamber.

"The altitude chamber actually places participants at the pressure level they'd experience at high and low altitude operations," said Alvarado. "It is not a simulation - what they experience in the chamber is what they experience in the field. That kind of realism is invaluable to their safety."

In the chamber, Aircrew personnel engage in both simple and complex tasks, like cartography, signal identification and other mental tests to see first-hand how hypoxia impairs their judgment and skills.

After their initial training in the altitude chamber, aircrew must requalify every five years. During retraining, participants have an opportunity to utilize the Reduced Oxygen Breathing Device, a new, cheaper alternative to the bulky altitude chamber that can better serve pilots specifically.

"The ROBD is worn just like a normal oxygen mask, except we can change the gasses in the mask to mirror the effects of hypoxia," said Tech. Sgt. Jennifer Kernan, 633rd AMDS aerospace and operational physiology flight chief. "Unlike the chamber, where participants know when we start to adjust the pressure, the ROBD lets us change their air intake without warning, so they really have to know when hypoxia sets in."

The ROBD doesn't simulate all of the effects of high-altitude, however, so the Air Force plans to combine the capabilities of the altitude chamber and the ROBD into an integrated system that stays cost effective without compromising the quality training already in place, said Alvarado.

"It is imperative we keep our aircrew safe with whatever tools we have at our disposal," said Alvarado. "Whether we use the ROBD, the chamber or a combination in the future, I know our quality of training comes from the expertise and commitment to the mission shown every day by our Service members in the chamber."