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DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING

İZMİR INSTITUTE OF TECHNOLOGY

SUMMER PRACTICE REPORT

IN

[TAI]

SUBMITTED TO: [Zübeyir ÜNLÜ]

SUBMITTED BY: [Mustafa Can AKBAŞ,150206013]

[Summer, 2011]

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TABLE OF CONTENTS

1)DESCRIPTION OF THE COMPANY.………………………………….………………..3

Company Name………………………………………………………..….….……………....3

Department Name………...……………………………...……………….….………………3

Company Location……………………………………………………………….…....…......3

Organizational Structure of the Company……………………………………………….......3

History and Main Area of Business of the Company………………………………………..4

Total number of working days of training……………………………………...……………6

2)INTRODUCTION…………………………………………………...…………………….7

3)LIST OF TASKS…………………………………………………...……………………...7

4)BODY OF THE REPORT…………………………………………………………………8

4.a) Briefing and the Factory Tour.…………………………………………………………..8

4.b) Informed about what FTI group do…………………………………………………….11

4.c) Introduction to Avionic Systems Education ……………………………………...……15

4.d) Informed about Data Acquisition, Calibration and Measurement Processes ………… 16

4.e) Software Engineering Education ………………………………………………………17

4.f) Informed about Avionics Data Buses …………………….…..…….………………….18

5)CONCLUSION……………………………….……………….………………………….20

References…………………………………………………………………………………...21

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1)DESCRIPTION OF THE COMPANY

NAME OF THE COMPANY

TURKISH AEROSPACE INDUSTRIES INC.

NAME OF THE DEPARTMENT

AVIONIC SYSTEMS-FLIGHT TEST INSTRUMENTATIONS

LOCATION OF THE COMPANY

Fethiye Mahallesi, Havacılık Bulvarı No:17

06980 Kazan-ANKARA / TÜRKİYE

ORGANIZATIONAL STRUCTURE OF THE COMPANY

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HISTORY AND MAIN AREA OF BUSINESS OF THE COMPANY

TAI was established on 15 May 1984 in Ankara, Capital of Turkey. The Turkish Armed

Forces Strengthening Foundation, the Undersecretaries for Defence Industries and the Turkish

Aeronautical Association are TAI's shareholders. TAI aimed to improve Turkey's national

power since it was established.

In TAI, co-production of F-16 fighters, CN-235 light transport, maritime patrol,

surveillance aircraft, SF-260 trainers, Cougar AS-532 search and rescue (SAR), combat

search and rescue (CSAR) and utility helicopters as well as design and development of

unmanned aerial vehicles, target drones and agricultural aircraft is among the products which

is in modernization or production. Furthermore, TAI is the prime contractor of the Turkish

Unmanned Aerial Vehicle (MALE) and the Turkish Armed Forces Attack Helicopter

production program. Also it is continuing designing and development working of Primary &

Basic Trainer (HÜRKUŞ) Aircraft.

152 F-16C/D aircraft was manufactured and delivered to the Turkish Air Force under

the Peace Onyx I Program between 1987 and 1995 80 F-16C/D aircraft to the Turkish Air

Force under Peace Onyx II Program between 1995 and 1999 and 46 F-16s to the Egyptian Air

Force under Peace Vector IV Program between 1993 and 1995. TAI also produced 34 SF-

260D primary trainers for the Turkish Air Force between 1991 and 1993 with AGUSTA of

Italy. TAI produced and delivered 50 CN-235 light transport aircraft to the Turkish Air Force

between 1991 and 1998 and six CN-235 Surveillance Aircraft for the Navy Command and

three CN-235 Maritime Patrol Aircraft for the Coast Guard Command between 1998 and

2003 with CASA of Spain. 30 Cougar AS-532 helicopters , 20 of whom is for the Turkish Air

Force and 10 of whom is for the Turkish Land Force were produced between the year of 1997

and the year of 2003.

There are a lot of modernization, modification and systems integration programs in TAI

and its core business also includes after sales support of both fixed and rotary wing military

and commercial aircraft that are in the inventory of Turkey. Electronic warfare retrofit and

structural modifications on TuAF F-16s, modification of the S-2E Tracker Maritime Patrol

Aircraft into Fire Fighting Aircraft, Black Hawk modifications for Special Forces,

modification and modernization of Cougar AS-532, Glass Cockpit Retrofit of S-70

helicopters, modification of CN-235 platforms for MPA/MSA missions for the Turkish Navy

and Coast Guard, the modification of ATR-72 platforms for the Turkish Navy as well as

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structural modification and systems integration activities required for the conversion of B737-

700 aircraft into AEW&C aircraft are major programs of TAI. Furthermore, TAI is the prime

contractor of the Erciyes program, which comprises the avionics modernization of C-130

aircraft that are in the inventory of the Turkish Air Force Command.

TAI is a qualified supplier for AgustaWestland, Airbus, Boeing, CASA, Eurocopter,

Lockheed Martin, Northrop Grumman, MDHI, Sikorsky and many more. TAI manufactures

sections 18 fuselage panels for Airbus A319/320/321 aircraft, wing tips and flight deck panels

for Boeing 737 aircraft, rear doors and engine cowlings for Eurocopter EC-135 helicopters,

horizontal stabilizers, tail rotor pylons and tail booms for Sikorsky S-70A and MH-60

helicopters, horizontal stabilizers for S-76 helicopters, MD-902 fuselages for MDHI and

AB139 fuselages for AgustaWestland. Moreover, TAI manufactures nose landing gear doors

for B747, Dorsal Fin for B777 and parts/subassembly parts of B737/767/777, wire harness

assembly for B737, piano panel parts for B777, and it also produces seven components of the

Cougar AS-532 helicopters. The center fuselage of Joint Strike Fighter (JSF) - F-35 aircraft

will be manufactured at TAI's facilities from February 2007.

To develop the Turkish Unmanned Aerial Vehicles program is among TAI’s miissions.

With the locally productions of MARTI, KEKLİK, TURNA/S, TURNA/G, GÖZCÜ,

PELİKAN and BAYKUŞ, TAI, which has gained experience in UAV technology, became

dominant in integration of subsystems to the platform.

Determined to follow global technological developments and be among the major

aerospace companies, TAI aims to be a leader of Turkey in aviation area in the 21st century.

TAI'S VISION: In the 100th anniversary of the Republic of Turkey; TAI, by possessing

indigenous/co- designed aircraft and satellites; seizing modern high technologies in

modification, modernization and production, and attaining global competitive power, will

become a world brand company with its devoted employees.

TAI'S MISSION: With our great leader Ataturk’s vision: "The Future is in the Skies"

and our nation's eagerness to "Build its own aircraft"; TAI has dedicated itself to be in the

skies and space and be pioneers in developing Turkey's aviation and space industry.

Projects of the company are in three groups which are; Aircraft Projects, Aircraft

Components and Satellite Projects, Helicopter Projects.

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Capabilities

• Design and Engineering

• Tool design and manufacturing

• Machining, tubing, welding and sheet metal fabrication

• Composite and metal bonding

• Electrical assembly

• Maintenance, repair and overhaul

• Integrated product support

• Quality systems

• Quality assurance

• Information technologies

• Training

Total number of working days of training

20 working days between 11 July and 5 August

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2)INTRODUCTION This summer practice aimed to be getting introduced with the business life, being

prepared to events that will happen in the future and adaptation to the working day; wake up

at 6:00 AM, start working at 7:45 AM and working until 5:30 PM with only a break time. In

addition to these, one of the main purposes was doing practices about the courses we learned

in IYTE. According to the these aims I tried getting close to engineer.

In my summer practise, I was interested in testing avionic equipments in Flight Test

Instrumentations department. Moreover, the engineers in my department was very helpful to

me. They give me some subjects to research about avionic systems. While I gave datas and

test results of the machines and also with the engineer’s helping to me, I felt like an engineer

in TAI, not an inturn. 3)LIST OF TASKS

Date Task description

11.07.2011 - 13.07.2011 Briefing and the Factory Tour

14.07.2011 - 22.07.2011 Informed about what FTI group do

25.07.2011 Introduction to Avionic Systems Education

26.07.2011 - 29.07.2011 Informed about Data Acquisition, Calibration and

Measurement Processes

01.08.2011 Software Engineering Education

02.08.2011- 05.08.2011 Informed about Avionics Data Buses

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4) BODY OF THE REPORT

4.a) BRIEFING AND FACTORY TOUR

4.a.i) My task was attending to educations and seminars given by TAI and making

factory tour with other inturns.

4.a.ii) Training took 2 days and the factory tour took 1 day.

4.a.iii) I think this educations aren’t interested with IYTE courses because these are

factory educations.

4.a.iv) I learned a lot of things about factory rules and concepts, business health and

safety and FOD and ESD.

4.a.vi) This task is compulsory in TAI to work as an inturn or an engineer.

In my first day, I went to sports hall in TAI fot orientation and firstly they controlled our

names. They had also wanted some documents for the security. We gave the documents and

lined up in sports hall and waited for getting identity cards. After getting identity cards, there

was a presentation about TAI’s history and working areas, rules that must be obeyed by

engineers and interns and about the application contidions for employment in TAI, privileges

provided by TAI to employers. There was a briefing about the Business Health and Safety

subject, FOD and ESD on Tuesday. We learned about factory safety concerns. On

Wednesday, we learned the department. My department was Avionics Systems. After learning

about avionics systems it’s wanted from us to choose a department to work with. I had wanted

to work at Flight Instrumentations Department and it was accepted. Finally I arrived our

section and get acquainted with the engineers in our section.

BUSINESS HEALTH AND SAFETY

TAI gives some important knowledge about business health and safety and wants every

workers to take this education preventing the work accident.

This education provide a positive health and safety culture to employees, meeting the

legal duty to protect the health and safety of employees and finding out how they manage

health and safety better.

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FOD (Foreign Object Damage)

Foreign Object Damage or Foreign Object Debris (FOD) is a matter that has potential to

cause damage to a vehicle or system. A foreign object can extremely be hazardous to plane or

any kind of machine. It may causes planes blow up while flying. This may results loss of

billion dollars to industry and also deaths. FOD costs the aerospace industry $1.1–$2 billion

USD per year in direct costs, and as much as ten times that amount in indirect costs from

delays, aircraft changes, incurred fuel costs, unscheduled maintenance, and the like for a total

of $12 billion USD per year.

Some FOD reasons:

• Dust comes from the air

• Broken machine parts

• Forgotten tools or excess wire parts while constructing plane

• Birds

Examples to FOD:

Air France Flight 4590

The crash of a Concorde, Air France Flight 4590, at Charles de Gaulle International

Airport near Paris on 25 July 2000 was caused by FOD; in this case a piece of titanium debris

on the runway which had been part of a thrust reverser which fell from a Continental Airlines

McDonnell Douglas DC-10 that had taken off about four minutes earlier. [4] All 100

passengers and nine crew on board the flight, as well as four people on the ground, were

killed.

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US Airways Flight 1549

US Airways Flight 1549 was a scheduled commercial passenger flight from New York

City to Charlotte, North Carolina, that, on January 15, 2009. Plane ditched in the Hudson

River adjacent to Manhattan six minutes after departing from LaGuardia Airport.

ESD (Electrostatic Discharge)

Electrostatic discharge (ESD) is the sudden and momentary electric current that flows

between two objects at different electrical potentials caused by direct contact or induced by an

electrostatic field.

People can carry about 10000V static voltage on. This high difference makes body

discharge sparks to integrated circuits or boards. There are also devices affected by small

electrical discharges about 10V. A spark is triggered when the electric field strength exceeds

approximately 4 - 30kV/cm, the dielectric field strength of air. In that case air becomes an

electrical conductor and allowing free electrons and ions pass through and this phenomenon is

called dielectric breakdown.

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4.b) INFORMED ABOUT WHAT FTI GROUP DO

4.b.i) My task was to be informed about FTI GROUP works

4.b.ii) 7 work days

4.b.iii) I think IYTE educations contribute me while studying how FTI groups take the

measurements. Circuit Analyze and Laboratory lessons help me when I was learning about

FTI group works.

4.b.iv) I learned a lot of things about department, what FTI group do.

4.b.vi) I think this task is important to recognize the department which you work.

Note: For strict security reasons I could only give some space just headings of some job I

involved in.

FTI GROUP

TAI has many sub-divisions. Flight test instrumentation (FTI) group is one of the

important ones. Group’s responsibility is to make:

• Design of required on-plane test instrumentation

• Provide test instrumentation

• Integration and implementation of test instrumentation

• Transformation of acquired data

• Confirmation of acquainted data

In short, FTI Group performs required test instrumentation for the on-plane tests. Job of

instrumentation design is carried out by taking account of some parameters:

• Choosing appropriate sensor

• DAQ system/card, signal conditioning

• Filter necessities

• Sampling rate

• Appropriate data record device and record capacity

• EMI/EMC necessities

• Power necessities

• Localization necessities

• Environmental factors

• Data transfer rates

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Capabilities:

• Vibration measurements

• Temperature measurements

• Avionic confirmation instrumentation

• Strain-Gauge measurements

• Force-Torque measurements

• Air-data system measurements,

• Electrical system measurements and etc

During my summer practice, testing department demanded some jobs. One of them is

about being able to use a data acquisition tool with MATLAB software by its DAQ toolbox.

My duty was to establish a connection with DAQ device via Ethernet and sending sampled

sinusoid waves to observe analog ones of them from one of its outputs. Also I took place in a

paratroopher door test. It was about measuring strain and force on the door in order to finalize

design.

Toolbox has commands helping in finding devices via computer’s connections. We can

create analog and digital I/0 adaptors for configuring DAQ devices. Sampling rates and

triggering is adjustable for engineer’s needs.

For instance:

AO = analogoutput('winsound',0) opens analog device.

chan = addchannel(AO,1) adds one channel to device.

set(AO,'TriggerChannel',chan(1)) set commands help us to adjust properties of our devices

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AVIONICS ELECTRICAL SYSTEMS

A plane has composed of there systems:

• airframe

• utility and

• avionic systems

 

First power systems are engines of plane. They provide impulsion for thrust which

makes plane fly. Lift, weight and drag forces are consequences thrust and plane itself.

Auxiliary power systems are compressed power and shaft power when enginees are

running and battaries, ground carts and ram air turbines even before actuation They are

seperated into three forms:

• Pneumatic (use of pressurized gas to affect mechanical motion) power system

• Hydrolic power system and

• Electrical power system

They also named as APU (auxiliary power unit), in short, whose main purpose is to

provide energy for functions other than propulsion.

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POWER SYSTEMS

These systems composed of DC and AC systems. Generally 28V dc is used on planes;

but some use 270V dc. The difference between two choices above is cable weight of plane.

For instance, a 280W heater allows about 1A current pass through for 270V dc system, but in

28V dc’s it is about 10A. The Ampere passing though cable massively effective on its length.

There are applications which uses currents up to 400A and channels having capacity of

12KW in 28V systems. Nowadays brushless electric motors are on outrun because of

expensive brush checkings. They are more efficient and reliable with overall reduction of

electromagnetic interference (EMI), more power, longer lifetime.

Figure 5 [9]

AC power systems are produced as 3 fhased 115Vac. In general, constant frequency in

AC systems is 400Hz. IDG (Integrated Drive Generator) produces that output. During flight a

plane flies with its 60 or 100 percent of speed. Plane needs to produce a constant power to

carry on its flight. CSD (constant speed drive) that is basically the transmission component of

the IDG which is made up of the CSD and the generator, stabilizes output rpm to produce 400

+/- 20 cycle operation.

System is also composed of transformer rectifiers (AC to DC) and Inverters (DC to AC).

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4.c) INTRODUCTION TO AVIONIC SYSTEMS EDUCATION

4.c.i) Task is to participate to the education.

4.c.ii) The education took 1 work day.

4.c.iii) IYTE lessons are not related to Avionics Systems. I learned about avionic

systems in this education in TAI.

4.c.vi) I learned briefly Avionics Systems. I recommend other students to attend the

Avionics Systems Education, if they are interested in aircrafts and its avionic systems.

Yasin Kaygusuz telled about the definition of avionic systems and the history of avionic,

architectures, cockpit. After these informations, Soner Uyar explained the radio systems on an

aircraft and Tolga İnan explained about recording control systems.

Avionic is the combination of two words, aviation and electronic: Avionic = aviation +

electronic. It comprises electronic systems for use on aircraft, aircraft satellites and spacecraft,

comprising communication, navigation and the display and management of multiple systems.

In this training, I have learned main components of avionic system and also learned that

avionic systems can be categorized, and main categories are aircraft avionic, mission avionic,

aircraft network. In this scope, it is indicated that the avionic systems are essential to enable

the filght crew to carry out the aircraft mission safely and efficiently. Even on an aircraft in

general aviation category, the avionic equipment is now relatively significant and can be in

the region of %10 of the total cost of an aircraft.

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4.d) INFORMED ABOUT DATA ACQUISITION, CALIBRATION AND

MEASUREMENT PROCESSES

4.d.i) My task was to be informed about data acquisition, calibration and measurement

processes.

4.d.ii) 4 day

4.d.iii) I think IYTE courses became useful while measuring and acquiring datas.

4.d.iv) I learned how to acquire datas, why calibration is necessary.

DAQ is acquiring electrical signals representing data gathered from real world

phenomena by using sensors and some kind of electrical instruments. Data is usually in digital

format. Any stimulus is convertible to electrical signals with appropriate sampling rates, for

instance, pressure, strain, force, vibration, light, heat, etc.

Testing instruments are based on acquiring data. FTI (Flight test instrumentation) Group

uses sensors provided from vendors with their software to process data and some

programming languages for representing results in a meaningful way.

Test instruments require calibration before any preparation. It is the first thing to do. It’s

the act of checking or adjusting (by comparison with a standard) the accuracy of a measuring

instrument. Process requires two devices: a calibration device providing required standards

and the unit under test (UUT).

Devices used for testing must have very high sampling rates in order to catch

instantaneous changes and be flexible, because various testing processes may require high

expenses for devices, for the kind of tests.

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4.e) SOFTWARE ENGINEERING EDUCATION

4.e.i) My task was to attend to software engineering education

4.e.ii) It takes 1 day

4.e.iii) I think IYTE courses are not related with this education.

4.e.vi) This education is important to know what software is and what is necessary to

make a good process in software,and I recommend attending this education to the other

students.

Software systems were designed for completing some tasks in computer systems.

Software can be defined as an interface between the problem domain and the solution domain.

There are some properties for the high quality in software. These are maintainability,

reliability, efficiency, stability and usability. Changings according to the needs of the

customer, can be provided by maintainability. The reliability is the property that is working of

software as expected in the particular time interval. Reliability is determined by Mean Time

Between Failure. One of the efficient properties of the software is efficient usage of the

system sources as like memory and processor by the software. Safety is determined by a

threshold. The other property, usability, is having enough document and user interface. Acting

conceivably in unexpected case is also the property of software. This is the stability property

of the software.

To obtain a good software work, it is necessary to be careful while applying software

development process. Software requirement specification, software design, code, test and

integration is important in the process. Being accurate, coherent, precise and testable is

necessary to get a high quality software.

There are some methodologies while processing of software.These are Cascade Model,

V Model, Spiral Model, Evolutionary Development, Prototype Model, Evolutionary

Prototype, Incremental Development.

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4.f) INFORMED ABOUT AVIONICS DATA BUSES

4.f.i) My task was to be informed about avionics data buses

4.f.ii) 4 day

4.f.iii) In my opinion, IYTE courses are not related with this education.

4.f.vi) This education is important to know which data buses are used in measuring and

acquiring.

WHAT MAKES AN AVIONIC BUS?

The important factors of avionics buses include:

Deterministic behavior, Fault tolerance, and Redundancy. Most avionics buses are serial

in nature. A serial bus using only a few sets of wires keeps the point to point wiring and

weight down to a minimum. MIL-STD-1553 (rev B) is the best known military example,

having been developed in the 1970s. The trend seems to be moving to Fiber buses, MIL-STD-

1773 being the fiber version of 1553. Switched fabric networks are used to provide Fault

tolerance. [1]

INFORMATIONS ABOUT BUS STANDARDS ORGANIZATION

The US Military uses terms like MIL-STD-xxxx (Military Standard-"Doc #"). The

United Kingdom (UK) uses DEF-STAN-xxxx (Defense Standard-"Doc#"), NATO calls their

specifications STANAG (Standard Agreement). In some cases US military standards are

transferred to a commercial standards agency for control. In these cases the military standard

is retired and the document takes on the name of the commercial agency. In the case of the

1553B bus, the name changed from MIL-STD-1553B (US government standard) to AS

1553B (SAE standard). Aeronautical Radio inc. produces many of the commercial avionics

standards, termed ARINC #. Of course the IEEE or ANSI controls many bus standards.

There are busses specific to test & instrumentation section bonded strictly to standards

those above. And they are just some of busses used by TAI. [1]

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Commercial used bus: ARINC 429

• Digital Information Transfer System

• Point-to-point, 2-wire Bi-Polar Return-to-Zero signal

• 32 bit data.

• 100K or 12.5K bit rate

Bus may use Williamsburg Protocol, which transferred blocks of data. It’s similar to

ARINC 575, but being replaced by 629. [1]

MILITARY USED BUS (MIL-STD-1553)

It’s a DOD Military (MIL) Standard (STD), which defines both the Mechanical,

Electrical, and Functional characteristics. MIL 1553 uses a Balanced (Differential) interface.

The interface is dual redundant with between 2 and 32 interface devices on the bus.

Communication over MIL-STD-1553 is half-duplex at a speed of 1Mbps using 75 ohm

copper wire cable.

NATO calls MIL-STD-1553B: STANAG 3838AVS; the UK calls it DEF STAN 00-18.

Now controlled by the SAE as AS15531, and re-released by NATO as STANAG 7155. [1]

Digital Data Busses and MIL-STD-1553. [12]

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5)CONCLUSION

My summer practise was about testing avionics equipments on aircrafts before flight. I

was interested in these avionics systems during the summer practise. It was very good and

nondescript experience for me. Furthermore, being in TAI as an inturn was also very useful

thanks to TAI’s helpful engineers. I think TAI is a world brand company with its devoted

employees in Turkey and it gives a lot of opportunities to engineers to work more efficiently.

After being with these engineers, i want to be a member of TAI. Even if it is exhaustive to

work in this company, I want to be and work there because of these good conditions of TAI.

In my summer practise, I have learned so many things about factory structure, avionics

systems, jobs doing by electronical engineers in TAI, data acquasition, testing types before

flight. We were informed about working areas of electronical engineers and almost everything

which can be necessary while working.

During the summer practise, i woke up at 06:00 Am, I started to work at 07:45 Am and I

finished working at 17:30. There was a break time between 12:15 and 13:15. Except this

break time, I was in the office and testing area in the factory. We were also tested avionics

equipments on C-130 aircraft and learned so many things about this equipments’ working

modes. All the devices were produce of modern technology. I researched also Data

Acquisition, Calibration and Measurement Processes and Avionic Data Buses and learned so

many things about these subjects.

I think the tasks i have done in TAI are sometimes related to lessons in IYTE. Circuit

Laboratory Lesson was become useful during the summer practise. I used oscilloscope,

measured power.

As a consequence, i am happy to be as an intern student in TAI. TAI has so

many division and sections and it has got working areas for an electronical engineer. If

you are also interested in aircrafts, working as an engineer or an intern in TAI is undefinable

happiness. I recommend it to other students for summer practice or as an engineer in the

future.

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REFERENCES

1 Davis, Leroy. December 19, 2008.

http://www.interfacebus.com/Design_Connector_Avionics.html

2 “According to the National Aerospace Standard 412”. National Association of FOD

Prevention, Inc.

3 “The Economic Cost of FOD”. Insight SRI Ltd. November 28, 2008.

http://insightsri.com/publications

4 “Foreign-Object Damage Cripples Concorde on Takeoff from Paris”. Flight Safety

Foundation Accident Prevention. April 2002. http://www.flightsafety.org/ap/ap_apr02.pdf

5 “Live Flight Track Log (AWE1549) 15-Jan-2009 KLGA-KLGA”. Flightaware.

January 15, 2009.

http://flightaware.com/live/flight/AWE1549/history/20090115/2026Z/KLGA/KLGA/tracklog

6 US Military Handbook DOD-HKBK-263

7 CRC Handbook of Chemistry and Physics

8 wrdnet.princeton.edu/perl/webwn

9 “[JSAP] Tokai University Unveils 100W DC Motor with 96% Efficiency”. Nozawa,

Tetsuo. Nikkei Electronics. Apr 3, 2009.

http://techon.nikkeibp.co.jp/english/NEWS_EN/20090403/168295

10 http://www.tai.com.tr/

11 http://www.elec-intro.com/mfd-simulator

12 http://www.altadt.com/support/tutorials/mil-std-1553-tutorial/