IFD Test Reports

The portable Intermittent Fault Detector (IFD) solved a long-standing intermittent / No Fault Found (NFF) issue in an F-16 Nose Landing Gear (NLG) Electrical Wiring Interconnection System (EWIS) that conventional wire test sets were unable to solve. The maintenance organization had been chasing the intermittent / NFF issues for a month. The IFD solved the EWIS issues in less than an hour.

IFD technology detected and isolated intermittent faults on a GE90 engine harness that was deemed “serviceable” in accordance with Aircraft Maintenance Manuals (AMM), Component Maintenance Manuals (CMM), and Fault Isolation Manuals (FIM) after being returned from a repair facility.

Rapport d’essai (Français)

The portable IFD is capable of detecting intermittent faults as short as 50 nanoseconds in duration. This test harness had intermittent events that were passing traditional continuity hard fault tests and high impedance tests. IFD detected and isolated these low-level micro-breaks and then, upon visually inspecting the harness connector, technicians noticed the existence of pushed pins, possibly manifesting due to over-tightening of the cannon connector.

This test was conducted leveraging the constant monitoring capability of IFD technology. With an IFD, a test window does not start and stop nor does it scan each circuit of a Unit Under Test (UUT) one at a time like conventional test equipment functions. Intermittence testing constantly monitors each circuit of the UUT simultaneously and continuously until the technician decides to end the test. This allows for environmental stimulus to be applied as was the case with this project. Tested pitot probes were subjected to a cold soak and then, as the probe returned to room temperature intermittent faults manifested, which replicated a commercial flight’s descent to land.

IFD technology is extremely versatile and capable of running traditional hard fault tests such as continuity, high impedance, shorts testing. The intermittence test used to detect and isolate intermittent faults is at the core of the IFD test suite. This projects highlights the full range of testing capabilities of the Portable IFD.

IFD technology is used to verify that LRUs / WRAs are intermittent free and will not cyclically return for repairs due to No Fault Found. It is also used to verify that Interface Test Adapters (ITAs) manufactured by Universal Synaptics and other companies are intermittent free. This report highlights how a “gold” asset was being utilized to verify an ITA. During that process, the “gold” or condition code “A” / Ready-For- Install asset was found to have intermittent faults, thus highlighting the advanced capability of Intermittent Fault Detection technology vis-a-vis conventional Automatic Test Equipment (ATE) that had certified the component as serviceable. This is a perfect example of the No Fault Found (NFF) cycle that costs the U.S. DoD in excess of $3B annually and, according to the ATA, costs commercial aviation an estimated $250K per aircraft per year.

Once an interface is built, IFD technology rapidly and automatically builds the UUT Test Program Set (TPS). No coding or time-consuming / expensive manual efforts by engineers and technicians are needed. Although beneficial, data, schematics, and technical orders are not required either. AutoMap leverages AI to assess the connected UUT and provide the true as-wired configuration of the asset. This project highlights IFD technology’s rapid adaptation power and speed that a technician can leverage to detect and isolate intermittent faults. OEMs spend months and even years, as well as unnecessary funds trying to get to the root cause of issues. IFD eliminates the guesswork and gives technicians the appropriate tool that is purpose-built to fill the intermittent failure testing void.

This project consisted of three separate test days, all leveraging the portable IFD tester and patch cable with a MIL-STD-38999 cannon connector. This interface allowed for rapid interfacing and adaptation leveraging the partners’ previously procured interface cables, made feasible due to the power of AutoMap. Cable set intermittent faults were detected and isolated allowing for repair. Intermittent-free cable sets were then leveraged to interface into the desired UUT for intermittence testing on those assets. Intermittent faults were detected and isolated in over 90% of the A-10 EWIS harnesses tested during this project.

This project highlights how conventional troubleshooting techniques and tools are used incorrectly assuming they can identify intermittent faults. Conventional test equipment and tools, such as DMMs, Meggers, etc., test one circuit or test point at a time and are not built to detect and isolate intermittent faults. Quality assurance for these AH-64 Apache harnesses was being conducted with a DMM, and as this report highlights, exacerbates the No Fault Found (NFF) problem. IFD quickly found the intermittent events that was missed by the conventional tools and methods employed.

This demonstration highlighted the rapid set up and ease of Test Program Set (TPS) development through AutoMap. Eleven unique TPS were developed in real-time over the two day test demonstration. This process for 11 TPS utilizing conventional ATE would take months of software coding and cost users unnecessary funds. The AutoMap feature application comes standard on every IFD.

This project highlighted the Intermittent Fault Detection & Isolation System™ (IFDIS™) ability to adapt, AutoMap™ and test with no data or schematics provided by the commercial carrier or the Line Replaceable Unit (LRU) OEM. All ELAC LRUs were shipped to Universal Synaptics and remained boxed until the commercial carriers engineering team arrived in Utah. Each ELAC was then unboxed and tested. Sixty percent (60%) of all ELACs tested had one or more intermittent fault, all ELACs had been certified ready for install (RFI) previous to IFDIS testing.