1. Industrial Training Report on
Non Destructive Testing (NDT)
GROUP: 05
AE-05
Team Members:
Submission Date: 17 December, 2015.
Motiur Rahman
ID: 201322028
Rushda Rahman
ID: 201322029
Mahfuza Sultana
ID: 201322030
Ahmed Shahriar
ID: 201322032
Md. Golam Sarwar
ID: 201322033

2. Introduction:
Biman Bangladesh Airlines is the national flag carrier of Bangladesh in the aviation sector
throughout the world. It was established as a corporate body called Bangladesh Biman
Corporation under the Bangladesh Biman Ordinance (Presidential Order No. 126) of 4 January
1972. Initially it started with a Second World War vintage Dakota, DC-3, a gift from the
Bangladesh Air force. Biman's domestic services with the DC-3 commenced within a month
after its inception. Now it has 14 fleet in active. Biman Bangladesh airlines has already signed a
contract to buy some more modern aircrafts such as Boeing 787, 777 and 737 in near future.
NDT section is a very crucial part of Biman Bangladesh Hanger Complex.
At a glance of Biman Bangladesh Airlines:
Head quarter Dhaka
CEO
Kyle Haywood
Hubs Shahjalal International Airport
Secondary hubs
Shah Amanat International Airport
Osmani International Airport
Flight root
25(International flight )
7 (Domestic flight)

3. Organogram:
Managing Director and
CEO
Director Engineering
an d Material
Management
Chief Engineer
(Engineering Production)
Principal
engineer
MCC
Deputy Cheif
Engineer
(Base
maintenance)
Deputy Cheif
Engineer (line
maintenance)
Deputy chief
Engineer
(component)
manager
hanger
complex
Principal
engineer-
IFE
Principle Engineer
(Base Maintainance)
Principal Engineer
(Base Maintainance)
Principal Engineer
(Support Shop)
Priciple Engineer
Specialized Services

4. NDT section of Base Maintenance organogram:
1. NDT In charge
2. Engineer Officer
3. Junior Inspection officer
4. Mechanic
Non- Destructive Testing(NDT)
Nondestructive testing or NDT is a wide group of analysis techniques used in science and industry to
evaluate the properties of a material, component or system without causing damage. The
terms Nondestructive examination (NDE), Nondestructive inspection (NDI), and Nondestructive
evaluation (NDE) are also commonly used to describe this technology. Because NDT does not
permanently alter the article being inspected, it is a highly valuable technique that can save both money
and time in product evaluation, troubleshooting, and research. Nondestructive testing (NDT) is the
examination of an object or material without destroying. NDT is performed to detect internal or external
imperfection, related information and characteristics without affecting the form, fit or function of the
test object .
In this report, we are going to write about some NDT method’s which we learned from the NDT Section
in Biman Bangladesh hanger complex .
Common NDT methods are:
1) Liquid penetrant Inspection
2) Magnetic particle Inspection
Principal Engineer
(Base Maintainance)
Engineer
(Base Maintainance)
Engineer
(Engine Buildup Shop)
Engineer
NDT

5. 3) Eddy current Inspection
4) Ultrasonic Inspection
5) Radiography (x-ray/gamma ray) Inspection
Liquid penetrant Inspection:
Initial inspection of the geometry of the component and the type and nature of the defect likely to be
present is the 1st
stage of any inspection. The inaccessible surface can be inspected by introscopes.
Miniature conventional cameras have been developed to examine internal condition of long parts. The
photographs can be taken by remote controls. Miniature television cameras have also been developed.
These transmit a continuous record of the inner surface of the parts,to be viewed on a monitoring
screen by the operator.
Procedure:
1. Clean and dry the surface of the component
2. Apply penetrant
3. Remove access penetrant
4. Apply developer
5. Reveal the flaw pattern under white light or ultraviolet light
6. Visual inspection
7. Post clean component
8. Crack reporting
Advantages:
1. Provide visual evidence cracks, porosity, laps, seams of other surface discontinuities
rapidly
2. Economically reliable
3. Easily portable
4. Can be used on aircraft or in the workshop.
5. Fairly simple method
6. Sensitive to fine, tight discontinuities
Limitations:
1. Can detect non porus surface discontinuity only
2. Difficult to use on very rough surface

6. 3. No easy method to produce permanent record
Figure: Liquid Penetrant Inspection
Magnetic Particle Inspection:
In order that minimum material be used for high strength, it is essential that minute irregularities and
discontinuities be discovered in the material. Magnetic-particle inspection is a non destructive method
for detecting flaws or defects in magnetisable materials, by which a visible indication of the defects is
produced on the surface of the part being inspected. This method will locate cracks and surface defects
in a wide range of products. The name “Magnaflux” is commonly associated with this process.
Procedure:
1. Component pre-cleaning
2. Introduction to magnetic field
3. Examine the test object under suitable lighting conditions for interpreting & evaluating
the indications.
Advantages:
1. Quantitative
2. Can be automated, apart from viewing
3. Simplicity of operation and application
4. Easily portable
5. It is quicker
Limitations:
1. Restricted to ferromagnetic materials

7. 2. Restricted to surface or near surface flaws
3. Not fail safe in the lack of indication could mean no defects or process not carried out properly
Figure: Magnetic particle Inspection
Eddy Current :
Eddy current tests are important test & widely used method within the broad field of
Nondestructive materials & evaluation. This method is particularly well suited for the detection
of service induced cracks usually caused either by fatigue or by stress corrosion. Eddy current
inspection can be performed with a minimum of part preparation and a high degree of sensitivity.
Eddy currents are electrical currents induced in a conductor of electricity by reaction with
alternating magnetic field. Eddy currents are circular & oriented perpendicular to the direction of
the applied magnetic field. The a) electrical conductivity b) magnetic permeability c) geometry
and d) homogeneity of the test object, all affects the induced currents. The electrical conductivity
& magnetic permeability of a material is influenced by its chemistry and heat treat condition.
Mixed lots of materials or parts subjected to fire or excessive heat damage can be quickly &
easily separated. Changes in the geometry & homogeneity of the test object will change the
magnitude & distribution of the eddy currents. By monitoring these changes, the presence of
cracks & other flaws can be detected.
Advantages:
1. Does not require couplant.
2. Gives instantaneous response
3. Is very repeatable

8. 4. Accurate for dimensional analysis of flaws
5. Extremely sensitive to flaws
Limitations:
1. Applied for conductive material only
2. Depth of penetration is limited
3. Lack of proper calibration of machine may occur error in crack detection
Figure: Eddy Current Inspection
Ultrasonic Inspection:
High frequency sound waves are introduced into a material and they are reflected back from surfaces or
flaws. Reflected sound energy is displayed versus time, and inspector can visualize a cross section of the
specimen showing the depth of the features that reflect sound.
Ultrasonic inspection is usually performed with two techniques:
(i) Reflection or “Pulse echo” technique
(ii) Through transmission technique. 'Pulse echo' technique is most widely used in aircraft
maintenance inspection
Advantages:
1. Thickness and length up to 30 ft can be tested
2. Position, size, type of the defect can be determined
3. Instant test result
4. Portable
5. Extremely sensible if required

9. 6. No consumables
7. Capable of being fully automated
Limitations:
1. No permanent record available
2. The operator can decide whether the test piece is defective or not while the test is in progress
3. Indications require interpretation
4. Considerable degree of skill is necessary to obtain the fullest information from the test
5. Very thin section can prove difficult
Figure: Ultrasonic inspection
Radiographic Inspection:
Radiography is one of the oldest and widely used nondestructive testing methods. A radiograph
is a photographic record produced by the passage of electromagnetic radiation such as x-rays or
gamma rays through an object onto a film. When film is exposed to x-rays, gamma rays or light
an invisible change called a 'latent image' is produced in film emulsion. The areas so exposed
become darker when the film is immersed in a developing solution. After development the film
is rinsed to stop development. The film is next put into a fixing bath and then washed to remove
the fixer. Finally dried so that it may handled for interpretation and record.
Advantages:
1. It is used to inspect a variety of nonmetallic parts
2. Excellent for detecting internal discontinuities

10. 3. Beam direction unaffected by part geometry
4. No calibration required
Disadvantages:
1. Radiation hazard
2. Limited depth penetration
3. Access to both side required
4. Orientation limitations
Figure: Radiographic Inspection
Conclusion:
This report has discussed on five common NDT methods and their advantages and limitations. The basic
purpose of this report is to give a detail idea on the NDT methods as well as a brief idea on the base
maintenance section of Biman Bangladesh Hanger Complex. This report is basically built on the
experience we achieved during our industrial training.
Reference:
1. MCM Issue-3 Rev 23 DISTRIBUTION
2. “Non-destructive Testing Applications in Commercial
Aircraft Maintenance.” By Md. Alahi Uddin Khan - Biman Bangladesh Airlines,
Bangladesh.
3. https://en.wikipedia.org/wiki/Magnetic_particle_inspection
4. https://en.wikipedia.org/wiki/Nondestructive_testing
5. https://www.biman-airlines.com/