A supply chain is only as strong as the weakest link and when it comes to the rotary aviation industry, weakness is prohibited. Notwithstanding unexpected delays in production and training due to the COVID-19 pandemic, the Corpus Christi Army Depot’s (CCAD) Non-destructive Testing (NDT) program ensures that it is the strongest link in the supply chain for the U.S. Army.
At CCAD, the ability to examine the internal structure of manufactured components identifying any flaws or defects is paramount prior to the assembly of an aircraft. Defects, undetectable to the untrained eye, are made visible by special testing methods known as Non-destructive Testing (NDT).
Prevention of defect development into a critical flaw is vital to risk reduction and safety principles. Internal detection of the minutest changes in thickness, corrosion, flaws and material density is critical to our mission.
John Quesada of the NDT Program Office explained that during the pandemic, CCAD delivered the proper training needed for inspectors, whether virtual or face-to-face, and continuously provided quality NDT support to the Warfighter.
Great care is taken ensuring that every single part that goes into an aircraft has zero defects.
Approximately, 80% of all NDT inspections performed at CCAD are penetrant and magnetic particle methods of inspections.
Type 1 penetrants have fluorescent dye in the liquid that illuminates under ultra-violet black lights making it easier for the human eye to detect defects in component characteristics or welding.
Only three methods of penetrant application and removal processes are utilized at CCAD- method A (water washable); method C (solvent removed); and method D (post emulsifier). Each method denotes the means by which the penetrant is removed from test specimens.
Magnetic particle inspections can only be performed on materials that are ferrous; i.e. can be magnetized. Once a part or component becomes magnetized, a fluorescent oil based solution, that has very tiny metal particles, is applied. Any cracks on or near the surface will cause a break in the magnetic field. This break will produce a positive and negative field at each end of the break. Just like the common horseshoe magnet, the break will attract tiny fluorescent metal particles at the break site.
The use of Radiography Inspection is familiar to most individuals who have had an X-ray. The test part is placed between the radiation source and film (or detector). CCAD uses direct Digital Radiography with Digital Detector Array (DDA) panels.
“From manufacturing, refurbishment, examination to final flight test, the U.S. Army is assured that components are defect free and the aircraft are ready to engage and improve combat readiness,” acknowledged Mr. Rod Benson, CCAD Chief Operations Officer.
The NDT Certification Program is responsible for the allocation of funds for critical training needs as it relates to industry standard recertification requirements.
According to Bryan McMillan, CCAD Workforce Development Division, collaboration between CCAD and Wichita State University (WSU) garnered high level training from Cowley College in Wichita, Kansas, for certification levels I and II. At the conclusion of the six-week training course, three NDT operators will be certified through comprehensive written examinations and hands-on examinations.
“The instructor led training provided was exceptional and fulfilled all requirements for NDT Level I & Level II. Both theory and application reinforced a technical understanding which enhances and ensures safety, quality and reliability for NDT examination processes,” said Yessica Hernandez, Division Chief, Directorate of Manufacturing & Process Production.
“The instructor’s aerospace experience was instrumental in providing and keeping with the type of training our NDT artisans require,” noted George Franco, Quality Assurance Specialist in the NDT Program Office, “Cowley College and WSU were invaluable for their assistance and participation in facilitating this training opportunity. We look forward to working together again.”
With supplemental training and the future deployment of new technology at the Depot, the natural progression of an Artisan’s lifecycle brings about the opportunity to bolster and enhance methods of prevention and detection.
CCAD continues to look beyond 2020, for more efficient and sustainable methods to safely inspect aircraft components. Recruitment and retention of a workforce that is trained in the latest technology ensures capabilities for future workload.