The enlisted maintainers from the Air Force's 27th Fighter Squadron - which flies Lockheed Martin F-22A Raptor fighters from Langley, Virginia, and is currently deployed to Okinawa, Japan, for training - use one of the earliest on-board diagnostic systems to help them troubleshoot the advanced fighter. Maintainers such as Staff Sergeant Brad Fobear plug laptop computers into the jets after each flight to see if anything is broken. The accuracy of the system has helped maintainers rapidly boost the Raptor's reliability since its 2005 introduction while also providing a detailed portrait of the improvement, Fobear reports. "When we started we had literally hundreds of fault cues that hit while we were flying. Now we're down to five or six."

In the wake of the F-22 integration, similar monitoring systems are being built into other new aircraft. San Diego-based IAC, in business since 2000 with around 60 employees, holds contracts to equip Army CH-47F cargo choppers and drones plus Air Force C-17 airlifters and the forthcoming Air Force HH-47 rescue helicopter with its Health and Usage Monitoring System. HUMS, a $40,000 black box connected to various sensors that can be installed onto almost any aircraft, constantly monitors the machine's condition, according to vice president Bill Lawler. He says HUMS processes massive amounts of data and reports only the relevant information to maintainers.

HUMS is based on open-source software that is tailored by IAC and the military in order to match HUMS to the quirks of a particular aircraft design. And the system plugs into a network connecting maintainers, military officials and industry representatives all over the world, so that they can swap maintenance tips while building a single database for a given platform's typical faults. The Army is even considering adapting HUMS to its Blue Force Tracker battlefield network, so that commanders can see critical maintenance data on the same screens that show the positions of vehicles across the battlefield.

While IAC has won contracts to install HUMS on some of the latest aircraft designs, so-called "legacy" platforms represent the biggest market, especially considering the wear and tear that Army aircraft are suffering in Iraq and Afghanistan. "It's a big aging aircraft issue," Lawler says. "Faults start to happen in different ways. You need a system that can be adaptive." With HUMS, he adds, "you actually have real data to say: here's a part that's starting to fail."

How much does HUMS help? "After-action reviews have expressed a 10-percent readiness improvement," Lawler says. "That's huge."