CIA&D Quality Assurance Team Exemplifies Integrity.
- Article by Jacey Allen
The Quality Assurance team at Co-operative Industries Aerospace & Defense (CIA&D) strives for continued improvement and success. As a key supplier of electrical wiring harnesses and interconnects to the aerospace and defense industry, quality is a critical aspect of the manufacturing process. Angella Martin, the Quality Assurance Manager at CIA&D, has been instrumental in CIA&D’s efforts of exceeding of customer expectations. Martin is relatively new to CIA&D, but has ample experience as a quality manager in the aerospace industry. Her background and knowledge bring fresh perspective to an already strong quality system.
For a department reliant on integrity and teamwork to get a quality product out on time, a good work ethic is essential to be a quality inspector. Martin attributes the department’s success to the inspectors’ experience, work ethic, and integrity and her trust in them to produce an exceptional part. Every harness produced must go through the department in order to be shipped to the customer.
. . . a good work ethic is essential to be a quality inspector. Martin attributes the department’s success to the inspectors’ experience, work ethic, and integrity . . .
To ensure our products are meeting and exceeding customer requirements, the industry standard must be met first. Throughout the whole manufacturing process, CIA&D employees follow the IPC/WHMA-A-620 industry standard for cable and wire harness manufacturing as well as the IPC J-STD-001 for soldering. Dale Roney, Chief Testing Engineer, and Martin are IPC/WHMA-A-620 certified and can train the quality inspectors on what is acceptable per the industry standard.
The Quality Assurance team under Martin has around a combined 100 years of experience in quality inspection. Throughout their collective time in the field, they correlate success to the utilization of teamwork and communication. Quality Assurance works closely with other departments at CIA&D, like engineering and manufacturing. The quality team visits the engineering department whenever there is a question about the engineering drawing or Manufacturing Process Sheet (MPS). The two departments are then able to reach an understanding of what conditions need to be met and the best resources to utilize to guarantee that a quality part is created. The quality and manufacturing departments also have a close working relationship due to the constant communication between the two. Failed inspections resulting in rework being the main reason for a line of communication.
However, there also needs to be good communication within the quality department in order to set priorities and verify conclusions if parts fail. Quality products shipping on time is the main goal of the department. Therefore, priorities need to be set because many parts go through the department at the same time. Troubleshooting electrical issues and verifying measurements when parts fail is critical, and communication is needed to reach valid solutions. Poor relationships would result in frustration between departments and delays. Both of which would hinder success. Therefore, teamwork and communication are imperative to the achievement of Martin’s goals for the team and CIA&D’s goal for an on-time delivery with quality performance at or above 90%.
Achieving these goals is no easy feat and requires diligence throughout the process for quality inspection. Luckily, our quality team is experienced in every aspect of inspection and each member is the epitome of integrity. Outlined is the process followed by our Quality Assurance inspectors from the reception of parts to the final product.
The Quality Process
The quality process begins well before assembly does with an inspection of parts received from suppliers. Every part must meet the specification and have the necessary documentation, such as Certificates of Conformance, before being incorporated into the wiring harness. In-house manufactured pieces must be inspected per the engineering drawing, as well, to confirm correct dimensions and materials. Attention to detail is of utmost importance during this step of the quality assurance process. A defective part could prove costly down the road in the assembly process. To combat the issue of receiving wrong parts or documentation, the receiving inspector must work with the materials department, engineers, and the supplier to find a solution that will meet the customer’s needs.
In-Process and Final Inspection
Once assembly has begun, it is crucial that the wiring harness is per the customer drawing and the MPS written by the engineering team. Harnesses are inspected during and after the assembly process to ensure mechanical and electrical properties coincide with the specifications.
Mechanical inspection is the physical inspection of the wiring harness or interconnect. Lengths are measured with either calipers or a form board to assure the harness is within tolerance. The form board serves as a template for the harness and is used with harnesses that have been built at CIA&D for an extended period and are in our Legacy program. If a harness is out of tolerance it can affect the acceptability of the harness. Too short and it will not make connection. Too long and it can affect weight. Weight for an aircraft is key because the heavier an aircraft is, the more thrust it needs to counter the weight. The keyways of the connector are mechanically inspected to make sure they can fit the mating connectors that will eventually be interconnected with the manufactured harness. The soldering done on the harness is inspected in accordance with the IPC J-STD-001 standard. The braid of the harness is checked for damage and coverage.
Also included in the mechanical inspection process is the visual inspection for Foreign Object Debris (FOD). FOD is a foreign object that would otherwise not appear in the harness and could potentially cause damage to the harness. CIA&D is careful to prevent FOD with connector dust caps and other precautions that promote a clean workspace. The quality team is a last line of defense for FOD prevention and must assure that all products are FOD free.
Electrical properties of the harness must be tested to ensure a working harness. Tests performed include: continuity, insulation resistance (IR), and shield to shield resistance.
Continuity is confirmation that the harness is wired correctly using the wiring diagram provided in the engineering drawing. If a harness is not wired correctly, it is important to catch during the in-process stage. Usually if a harness is mis-wired, the harness needs to be opened and rewired. Most harnesses are electrically inspected before and after over-braiding to avoid having to open and scrap the braid if wired to a fault.
An IR test analyzes the leakage of current through the insulation of the conductors. The test applies Ohm’s Law and hipotting. Hipotting is the use of high potential also known as high voltage. By sending through a direct current (DC) voltage lower than the voltage for dielectric testing, the current value being leaked through the insulation is measured. The insulation resistance is then calculated by dividing the current into the voltage, per the definition of Ohm’s Law. The insulation resistance should be very high since the leaking current should be low. This resistance characterizes the quality of the insulation between two conductors and gives a good indication of the risks of leakage currents flowing. (Carelabs, 2019)
The last common electrical test is shield-to-shield resistance. This is measured with a multimeter by placing two leads on each end of the harness on either the backshell or braid near the connector. The resistance should be low, or fractions of an Ohm. High resistance is most likely due to a component shorting to the shield.
Automating the Harness Testing Process
At CIA&D, many harnesses are tested electrically with an automatic Hipot Tester by creating test harnesses that include the mating connectors. Programs are then created to execute the necessary tests required by the customer. These automated tests are preferred for they are far more accurate than manual testing and allow for easier documentation of results. However, if a test harness is unavailable, then manual electrical testing must be performed. This is often the case for harnesses that are being built for the first time and are still in development. Our Quality Assurance Inspectors would, in this case, use a multimeter to check for continuity and shield resistance per the wiring diagram. The insulation resistance can be tested on a non-automated Hipot tester. There would be no computer program, but the parameters for the test would be entered manually and then tested.
If a harness is to fail at any point during quality inspection, the harness is returned to the manufacturing floor to be fixed. An explanation of why a harness failed is included and a deadline of one work day is given for corrections so that the harness can be re-inspected and shipped to the customer on time. The planning team at CIA&D prepares for possible rework and works it into the lead time for the product so minor hiccups do not cause major delays.
Another aspect of Quality Assurance that is imperative is documentation. Every inspection requires an inspection record and electrical test results. The inspection record documents the procedure for inspection. All dimensions measured, tools used, and tests completed are recorded. The inspection record closely follows the engineering drawing by accounting for every note included on the drawing. If an automated test was not performed, then the values for the manual test are noted on the inspection record. A First Article Inspection (FAI) report is frequently written for a first piece build. This report is further documentation that the customer requirements and industry standards were met throughout the whole manufacturing process and that every step was followed to the letter. Documentation is important to prove to the customer they can be certain that their harness meets their needs.
About Co-Operative Industries Aerospace & Defense:
CIA&D is an AS9100 registered company based in Fort Worth, Texas. The company develops and manufactures electrical wiring interconnects, ignition leads, and flexible conduits for airframe, engine, and ground support equipment for a number of prime contractors. In addition to manufacturing capabilities, Co-Operative Industries also provides Part 145 repair services such as check & test, overhaul and repair, and S/B incorporation for many of the commercial aircraft wiring harnesses in service today (FAA No.: OI0R891N, EASA: EASA.145.5897, CAAC No.: F00100406).