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How Lockheed Is Using Intermittent Detection to Diagnose Fighter Jet Faults

Lockheed Martin is partnering with the only company with a practical intermittent fault detection solution to offer the military a panacea for an ailment costing it billions in inefficiency: the inability to diagnose intermittent faults in avionics.

Lockheed Martin is partnering with the only company with a practical intermittent fault detection solution to offer the military a panacea for an ailment costing it billions in inefficiency: the inability to diagnose intermittent faults in avionics.

Military aircraft reporting electronics errors are later tested only to show no fault around half the time — a major contributor to U.S. Defense Department non-value costs on the order of $2 billion, according to Jason Brooks, Lockheed Martin’s deputy program director of support equipment solutions.

It’s called an intermittent fault, and mounting frustration with equipment that “fails in a working environment” but shows nothing wrong when pulled for testing led the DoD to start a joint service effort in 2012 focused on addressing the problem, which really ramped up in recent years.

“If you go back to the [General and former Secretary of Defense James] Mattis memo about 80 percent mission capability, this is a huge driver in being able to affect that,” Brooks said. “If you think about a piece of equipment that goes up, goes into fail mode and you don’t have that [line-replaceable unit] that you can plug in, that aircraft is down until you can replace that piece.”

The problem with intermittent fault detection is two-fold: First, common faults are caused by things such as a loose solder joint or ribbon cable that only reveal themselves to be problematic under certain vibrations or G-pulls —stresses that they’re generally exposed to exclusively in-mission.

Second, traditional testing entails the evaluation of one circuit at a time through the use of an oscilloscope, serially scanning each individual one.

“That meant that the testing had to occur at the same time as the fault, and the chances of that are just infinitesimal,” according to Ken Anderson, president and CEO of Universal Synaptics.

Lockheed and Universal Synaptics are trying to change that with a partnership based around the latter’s intermittent fault detection technology. Lockheed is the system integrator, provides the equipment and system analysis, working with the customer to tailor the solution to their needs. It will also lead program management and sustainment.

The much-smaller Universal Synaptics — a company of about 20 people, half operations and half engineering or technology — provides the solution. Brooks said that Lockheed “watched this company for a while” because of the technology it was developing before they went into business together, while Anderson is aware of the benefits a small company like his can get from partnering with a global presence, from industry experience to brand awareness — and certainly resources.

“But I think what really kicked it off and got it started for us — a lot of the platforms [that the intermittent fault detection technology has been used on] are Lockheed platforms,” Anderson said.

Universal Synaptics and Lockheed are offering two customizable options for intermittent fault detection in avionics and wiring systems: the portable Voyager and the rack-mounted intermittent fault detection & isolation system 2.0 (IFDIS), for use in shops.

Compared to the normal one-point-at-a-time testing, Voyager can test up to 512 points, while IFDIS is expandable in 1,280-point increments with no functional limit — for more complicated systems, 8-to-10,000 might be required.

Voyager, which travels in a large briefcase, is also available in 128- or 256-point configurations and provides the same real-time testing results as IFDIS.

Where IFDIS has an advantage, beyond number of test points, is the testing environment. It is housed in a chamber that is designed to replicate some of the stressors a piece of equipment might experience in flight. If a ribbon cable only comes loose during high-vibrations, the testing environment can expose it to that to get the fault it is looking for.

Lockheed Martin F-35s.Lockheed Martin

IFDIS and Voyager, which are the only automated test systems that currently meet the DoD’s MIL-PRF-32516 standard for intermittent fault test equipment, can also leave the fault-found realm and drift into predictive functionality.

“Since our capability is like a neural network, if it’s got 500 or 8,000 test points, it sits on all those test points and waits for something to fail and waits for it to tell you ‘On these 20 different connection points, you’ve got an issue,’” Brooks said. “And it will say ‘On these next 20, you’ve got an issue where it’s starting to get intermittent, starting to get loose, you may want to go ahead and address them.’ So, it’s not only solving the current problem, but it’s also forward-looking.”

The Mattis memo Brooks referenced on mission capability specifically names the F-16 Fighting Falcon, F-22 Raptor and F-35 Lightning II — all Lockheed Martin offerings — as well as Boeing’s F/A-18 Hornet/Super Hornet as targets for improved readiness to help with efficiency.

“The great thing about this technology is, the tester itself is agnostic; it doesn’t care what it’s testing,” Brooks said. “It’s basically just the capability testing the number of circuits. The part that’s unique to each piece of equipment is the adapter that Lockheed Martin provides. A customer may want to test F-16 and F-22 at a specific site, so we’d size the tester to meet both and the cables [for connecting to the equipment] would be different.”

Currently, six IFDIS platforms have been deployed to a Lockheed facility and “a dozen or so” Voyager units have been deployed for foreign military use.

At a busy site, such as a regional repair center of certain bases, Lockheed would recommend multiple IFDIS units to handle the throughput, while some are fine with just one unit.

The company is currently talking with “decision-makers with every branch of the U.S. military and some foreign militaries,” and Brooks said it is targeting 2019 or 2020 to start delivering systems.

“From a capability perspective, we’re doing everything proactive to look at production lines on Voyager, IFDIS and [connector equipment], to make sure we’re ready for when orders start pouring in,” Brooks said. “There’s a period of defining requirements, putting orders in and acquisition … There are many in the U.S. government and foreign governments that want this capability right now.”

If people do want that capability, Lockheed and Universal Synaptics are pretty much the only game in town.

“With our current capability, I believe we have the solution set for the no-fault-found problem,” Anderson said. “One thing we have to be cognizant of is that nobody is really doing what we’re doing, so we’re sort of out-developing ourselves. There isn’t really anybody knocking on our door.”

Anderson said there would be additional iterations in the product — miniaturization, perhaps — but that the company had to be careful about its development schedule.

“We’re talking about pacing ourselves, and we’ll do this one in two years and this one in four years and that way we’ll stay so far ahead of the innovation curve,” he said.

Already, Universal Synaptics has cut the shortest-duration intermittent fault it can detect from 300 to 50 nanoseconds, and Anderson said more is possible with some design enhancements.

“I can pull the trigger tomorrow and we can get shorter-duration intermittent faults,” he said. “But, when you look at what the next-closest piece of equipment is, the shortest they can do is 17 milliseconds, and that’s if they happen to be on the failing circuit at that specific moment in time.”