While most NDI services are Part 145 repair stations with a repair station manual they may also perform their work to an FAA approved process specification. These should be noted by the auditor in the preparation phase of the evaluation. Work instruction and internal procedures for management of the various inspection techniques must be reviewed. Personnel who perform NDI inspections should be at least a Level 2 and certified using one of the following standards:
- The American Society for Nondestructive Testing (ASNT) Standard SNT-TC-1A Recommended Practice No. SNT-TC-1A: Personnel Qualification and Certification in Nondestructive Testing
- AIA-NAS-410, Aerospace Industries Association, National Aerospace Standard, NAS Certification and Qualification of Nondestructive Test Personnel.
- ISO 9712, International Organization for Standards, Nondestructive Testing -- Qualification and certification of personnel.
- Air Transport Association (ATA) Specification 105, Guidelines for Training and Qualifying Personnel in Non-Destructive Testing.
The standards establish minimum requirements for certifying NDI personnel. The NDI provider’s internal maintenance procedures will identify the standard that personnel are certified to. The training program will describe the classroom and experience requirements for technicians at each level.
Level 1: Can accomplish equipment calibration and may perform inspection under supervision of a Level 2 or 3 technician.
Level 2: These are journeymen technicians able to perform the inspection, interpret result, and document the results of the inspection.
Level 3: In the NDI world Level 3 technicians may design inspection techniques and processes. However in aviation, where much of the work is related to ADs or other approved data, the ability to design a deviation is of little use unless an alternate means of compliance is needed. The Level 3 will likely be the prime mover in the training and certification program as well as the supervisor of much of the work.
Each technician must have a current eye exam. The Jaeger eye chart is commonly used to test near vision of NDI technicians and can be administered by an optometrist, or someone designated by the repair station through its internal procedures.
Inspections are conducted using manufacturers’ instructions. Repair station quality manuals describe the means of assuring that technical data is current. The audit should review technical data for currency to those standards.
Need some help?
Feeling a little lost? NDI is a major form of inspection. Entire books have been written on its processes. But we are just trying to decide if the NDI provider is the right choice for our airplane. In the time it takes to accomplish an audit you can make a reasonable determination of an NDI provider’s suitability to work on your aircraft. There is plenty of help on the Internet to get you started. A very reasonable checklist developed for FAA safety inspectors and can be downloaded at: www.faa.gov/aircraft/repair/become/media/NDICKLIST.doc.
Vern Berry began his aviation career as an A&P mechanic in 1979. His experience in aviation includes key management roles in quality and safety for both MRO and air carrier operations. He manages a consultant firm at www.blowntireaviation.com.
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