NASA's New Spacecraft Air Leak Sensor
This sensor developed by Iowa State University researchers can detect leaks on spacecraft.
Credit: Iowa State University

An air leak sensor under development by an Iowa State research team is finally ready for installation as a prototype on a NASA spacecraft. Air leaks are notoriously difficult to find, because instruments and other gear cover most of the interior surface of spacecraft.

At present, astronauts aboard the International Space Station (ISS) use microphones to listen for the telltale hiss of air escaping into space. However, most of the sound energy goes out into space along with the air.


To give you some idea of the scope of the problem, consider the leak that developed on the ISS in January of 2004. The leak, which turned out to be just one millimeter wide, took several weeks to find and patch. If the leak had not been found, the astronauts would have been forced to return home.


The new air leak sensor (see photos) uses structure-borne vibration to detect the direction of the leak. The one-inch square sensor includes an array of 64 elements that detect vibration. The different elements pick up vibrations at different times. The data is analyzed by a computer to determine the direction of the leak; multiple sensors reduce the amount of time to detect a leak to a approximately one minute.


The research team is being lead by Dale Chimenti, and Iowa State University professor of aerospace engineering. The other team members are Stephen Holland, an assistant professor of aerospace engineering; Ronald Roberts, a scientist for Iowa State's Center for Nondestructive Evaluation; Ricky Reusser, a recent Iowa State graduate who earned his bachelor's degree in aerospace engineering; and Steven Sulhoff, a senior in aerospace engineering from Avoca.


Chimenti's team is now working with Invocon, a company that has already provided sensors to the ISS. If NASA approves Phase II funding, an air leak system will be prepared for installation.


Creative thinking about air leaks in space preceded the actual space program. Science fiction writer Robert Heinlein came up with a more colorful method in his 1948 short story Gentlemen, Be Seated, which described life in a lunar habitat.

"There were perhaps a dozen bladder-like objects in the tunnel, the size and shape of toy balloons. They seemed to displace exactly their own weight of air; they floated without displaying much tendency to rise or settle. Konski batted one out of his way and answered me before I could ask.

'This piece of tunnel was pressurized today,' he told me.


'These tag-alongs search out stray leaks. They're sticky inside. They get sucked up against a leak, break, and the goo gets sucked in, freezes and seals the leak.'"

(Read more about Heinlein's tag-alongs)


Robert Heinlein had some other creative ideas about space engineering; these articles compare his fictional solutions with the real thing:


HyperBike - NASA-Supported Heinlein Lunocycle?

This unique bicycle combines elements of old-fashioned big wheels and racing wheelchairs. NASA's interested, too.


Heinlein's Giant Waldo Comes To Life

Engineers and scrap metal artists worked hard to bring this enormous robotic hand to life.


Launch Ring Magnetic Launch System

Although just in the planning stages, this could give us a twist on an old Heinlein suggestion for reaching space.


Read more in the Iowa State news release; story via Roland.


(This Science Fiction in the News story used with permission of - where science meets fiction)