Intermittent electrical faults are more than just a nuisance to DoD maintainers. They cost the DoD about $2B a year in inspection and re-inspection, repair, replacement, and spares. Unlike a failed electrical component, or an open or a short in a circuit, which you can usually find and isolated by a systematic process of elimination, locating intermittent or steady state electronic faults is like chasing ghosts. One moment the fault appears, the next it disappears. Intermittence occurs randomly in time, place, amplitude and duration. Electromechanical devices go into a long and frustrating period of low-level intermittency as their mechanical tolerances change. It only takes one undetected and hence unrepaired intermittent circuit in an electronic box to cause it to randomly malfunction. The replacement of these assemblies is a major contributor to an annual intermittence faults cost of $2 Billion within the DoD. It is therefore very important that all intermittent circuits that are present in these boxes be detected, isolated and repaired. With the proper test equipment, it is now possible to detect and repair these intermittent circuits and steady state electronics. This virtual technology forum will provide examples of intermittence testing currently in use within the military Services, discuss the benefits and challenges of each, and talk about new technology being developed and demonstrated.
Troubleshooting Intermittent & Steady State Electronic Faults
JTEG Forum Minutes
Event: On 25 July, 2017, the Joint Technology Exchange Group (JTEG), in coordination with the National Center for Manufacturing Sciences (NCMS), hosted a virtual forum on “Troubleshooting Intermittent & Steady State Electronic Faults”.
Purpose: The purpose of this forum was to provide examples of intermittence testing currently in use within the military Services, discuss the benefits and challenges of each, and talk about new technology being developed and demonstrated.
Welcome: Ray Langlais (LMI) welcomed everyone to the forum, thanked the presenters and all the listeners for their attendance, and briefly previewed the agenda.
Administrative: This was an open forum. The presentations, along with questions and answers, were conducted through Adobe Connect. A separate audio line was used. Approximately 40 participants from across DOD and industry joined in the forum.
IFDIS at NAVAIR – Fernando Zuniga, COMFRC, Laurie Zuniga, and Ken Anderson, Universal Synaptics discussed the IFDIS F/A-18 GCU pilot with FRCSW (North Island), FRCW
(Lemoore), and PMA265 concurrence, to gather additional data including potential Time On Wing (TOW) increases that could result in improved F/A-18 Readiness. COMFRC is partnering with the NAVAIR JIT @ Lakehurst ahead of the acquisition of IFDIS for additional avionics components, partnering with NAVSUP to pilot 10 GCUs through the workflow process as a time study for process improvements, partnering with industry via CRADA’s to test portable units on A/C and helicopters, and collaborating with the PMA’s to identify additional avionics components that are candidates for Intermittence Testing.
There was a healthy discussion on the future implementation of IFDIS and what challenges exist to include culture change, lack of requirements, the need and cost to demonstrate IFDIS and build TPS’ for each individual WRA/LRU, and limits in funding and manpower to conduct the demonstrations and BCAs.
Automatic Wire Test Set Technology – Phil Mathis (160th SOAR(A) Fort Campbell) described the 160th certification test protocol for the following:
- Automatic Wire Test Set (AWTS) the following test programs employed:
- MH-47G Full Authority Digital Engine Control (FADEC)
- MH-6M Full Authority Digital Engine Control (FADEC)
- 45 LRU Test Programs Locally Developed at the Special Repair Activity
- Near term test programs under development:
- MH-60M Digital Automatic Flight Control System (DAFCS)
- MH-60M Engine Harnesses (YT-706 Engine)
- Future program development:
- MH-47G DAFCS, Digital ICS, ASE, & Common Avionic Architecture System (CAAS)
- MH-6M Weapons Systems
NAVAIR Fault Detection Capabilities – Brett Gardner (FRC-SW) provided an overview of FRC-SW’s Advanced Technology Innovation (ATI) intermittent wiring initiatives.
- IFDIS was originally an Air Force SBIR project with Universal Synaptics. The system was implemented at FRCSW as a CIP project 2015/16 SBIR phase 3 purchase and IFDIS installed in 2015. FRCSW Pilot program to evaluate impact to Depot $$ to implement IFDIS testing. 10 F18 Super Hornet GCU’s will be evaluated.
- Ncompass/Voyager – Cooperative Research and Development agreement (CRADA) to demonstrate technology on F18 and other Navy platforms using AWTS TPS wiring harness. Nose steering cable and CGU AC cables have been obtained.
- AMUET – FY18 demonstration of technology on F18 and other platforms. Nose steering cable and GCU AC cables are the initial systems of interest, other systems tested as funding and time permits
- CRADA with Eclypse International to demonstrate intermittence capability of AWTS. Software updates to AWTS to provide for intermittence capability. Collaborate with 4.8 Lakehurst to verify intermittence capability of AWTS. Anticipate Oct 18 start date.
Advanced Mobile Universal Electrical Tester (AMUET) – Frank Zahiri (WR-ALC) provide a description of USAF testing with AMUET including:
- Expanded testing of AMUET on multiple cross-Services aircraft (C-5, C-130, F18) electrical subsystems, and validate benefits via a BCA
- Funding through FCT (Foreign Comparative Testing) with an Air Force Cybersecurity/IATT (Interim Authority To Test) one year extension requested
- CTMA Contract Mod for NAVAIR F-18 aircraft electrical subsystem(s) for AMUET testing in progress
- Status: AMUET is small, portable, fast and easy visual training, setup, and testing, has a wide range of tester and wiring troubleshooting capabilities, requires fewer technicians than USAF Standard Tester, short lead time, cost and perhaps less complex execution for new subsystem’s TPS (Test Program Set)
Closing Comments: Ray Langlais thanked the presenters for their contributions and the audience for their participation. He suggested continuing the information exchange beyond the forum and the importance of teaming/partnership to the DoD maintenance community.
- Obtain “public release” versions of the presentations and post to the JTEG website. These meeting minutes, the Q&A, and those briefing slides approved for public release, will be posted on the JTEG website at http://jteg.ncms.org/ . (All presenters, LMI, NCMS)
Next JTEG Meeting: The next JTEG virtual forum is 29 August, 1:00 – 3:00 pm EST. The topic is “Non-Destructive Inspection (NDI)”.
POC this action is Ray Langlais, email@example.com , (571) 633-8019
IFDIS at NAVAIR – Fernando Zuniga, COMFRC
Q1. How were the GCU’s historically tested before IFDIS? Multi-meter? Dedicated test set?
A1. Multi-meters, visual inspections, and even manually for the Super Hornets.
Q2. How user friendly is this device? You mentioned that it was brought to your attention by the USAF, but I’m led to believe that the AF isn’t using it. If it generates such success then I’m scratching my head as to why they would have stopped? Any ideas?
A2. It is a culture change for the workforce. A reduction in time to [perform the work, results in less OT or even working your way out of a job. To prevent that feeling, you must ensure there is additional work lined up…there are lots of components out there. Reference the USAF, they had some issues, but will be back up operating shortly. One of the common challenges to acceptance is the PM’s needing an existing requirement. One USAF approach to meet that requirement, is to look at IFDIS as automated way to trouble-shoot the chassis. A major issue is that each LRU or WRA is being treated as needing their own approval. That requires developing a TPS, testing, and a BCA for each component to gain acceptance. With limited manpower and funding, that is extremely difficult to accomplish.
Q3. Is this type of technology going to be developed for other systems, IE, I primarily deal with surface navy SLQ-32, intermittent faults are a pain to troubleshoot.
A3. Yes, but see above. Using IFDIS on a new system currently requires a new TPS, testing, and BCA to gain approval.
COMMENT: For the Eclypse AWTS technology example – word of mouth internally by the military helped spread the word. It doesn’t happen overnight.
Automatic Wire Test Set technology – Phil Mathis (160th SOAR(A) Fort Campbell)
Q1. Interested in knowing how you build the backshells if you are having issue with continuity.
A1. We don’t build harnesses locally for the aircraft. Based upon the fact that we have failure on our new build aircraft that have less than 300 Hrs we can only surmise that the harnesses were improperly built in the factory. Do realize that the Isodyne backshell installation practice is not in the General Practice (NAVAIR 1-505-1). Olliie Muja at NAVAIR has an action to include these tool-less backshell into the manual. Therefore most of the legacy backshell failures may be caused by improper installation practices.
NAVAIR Fault Detection Capabilities – Brett Gardner (FRC-SW)
Q1. No Questions
Advanced Mobile Universal Electrical Tester (AMUET) – Frank Zahiri (WR-ALC)
Q1. Does the AMUET need TPS’s developed for Testing?
A1. Yes, TPS’s and procedures are required of course. We use a digital format, not a program. We use common connections so it is much faster and reduces costs.