CHAPTER 15
NONDESTRUCTIVE INSPECTIONS, WELDING,
AND HEAT TREATMENT
Chapter Objective: Upon completion of this chapter, you will have a basic
knowledge of nondestructive inspection (NDI) methods, welding procedures and
equipment, and the different forms of heat treatment.
In this chapter, we will discuss the basic principles
and procedures of nondestructive inspections, welding,
and the heat treatment of metals. These three areas
require special training, and in the case of non-
destructive inspections and welding, they require
special certification prior to performing these two
functions. While not all AMs are required to become
NDI operators, aeronautical equipment welders, or have
the need to perform heat treatment of metal, there is the
need to be familiar with these procedures and how they
apply to the AM rate. The information in these areas is
being presented in a broad nature. For a more detailed
discussion of these procedures, refer to the applicable
technical manuals.
NONDESTRUCTIVE INSPECTION
PROGRAM
Learning Objective: Evaluate the background
and personnel training required for the NDI
program and the various NDI personnel
qualifications.
In the hands of a trained and experienced technician,
nondestructive inspection (NDI) methods allow
detection of flaws or defects in materials with a high
degree of accuracy and reliability. It is important that
you become fully knowledgeable of the capabilities of
each NDI method, but it is equally important that you
recognize the limitations of these methods. The non-
destructive inspection methods covered in this chapter
serve as tools of prevention, which allow defects to be
detected before they develop into serious failures.
During the inspection of aircraft, it is essential that
faults are found and corrected before they reach
catastrophic proportions. In applicable areas, NDI can
provide 100-percent sampling with no affect upon the
use of the part or system being inspected. The effective
use of NDI will result in increased operational safety,
and in many instances, dramatically reduce maintenance
man-hour expenditures.
NDI is the practice of evaluating a part or sample of
material without impairing its future usefulness. The
methods used in naval aviation include, but are not
limited to, visual or optical, liquid penetrant, magnetic
particle, eddy current, ultrasonic, and radiographic. The
success in their use depends heavily upon intelligent
application and discriminating interpretation of results.
NDi is performed only by qualified and currently
certified NDI personnel, and in accordance with NA
01-1A-16, Nondestructive Inspection Methods manual.
This is a general manual covering the theory and general
applications of the various methods of NDI.
The Aircraft Nondestructive Inspection School,
located at NATTC Memphis, Tennessee, provides NDI
technician training for both military and civil service
personnel. Career designated (grade E-4 and above)
Navy aviation structural mechanics (AMSs), Marine
Corps structural mechanics, and equivalent civil service
personnel are eligible for the course. In addition, NDI
operator training in liquid penetrant, magnetic particle,
and eddy current methods; refresher training; and
recertification of NDI technicians are provided by the
Naval Aviation Depot (NADEP) and ACC/TYCOM
designated NDI specialists. Information pertaining to
curriculum, quota requests, obligated service require-
ments, and, where applicable, convening dates is
published in the NAVEDTRA 10500, Catalog of Navy
Training Courses (CANTRAC). Requests for NADEP
training and authorization for recertification of NDI
technicians who have been inactive in NDI for more
than 1 year must be made, via the chain of command, to
the cognizant ACC/TYCOM. If the request is approved,
the ACC/TYCOM will advise which NADEP is to be
used.
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