HindustanAeronauticsLtd. Paper Contributed by Kajal updated on Mar 2019

                                          HAL Placement Papers


In HAL written test the first section contains Aptitude questions and the next section contains Technical questions. The aptitude consists of multiple choice questions. Here are a few questions asked in the Aptitude section and Technical section of HAL written test:


1. Aptitude Questions with Answers


1. 35% of 160 +?% of 180 = 50% of 310


(a) 35

(b) 55

(c) 65

(d) 45

(e) None of these


Answer: b


2. A man complete a journey in 10 hours. He travels first half of the journey at the rate of 21 km/hr and second half at the rate of 24 km/hr. Find the total journey in km.

(a) 220 km
(b) 224 km
(c) 230 km
(d) 234 km


Answer: b


3. ?3781 x 5.36 = ?


(a) 350

(b) 330

(c) 240

(d) 280

(e) None of these


Answer: b 


4. Find the wrong number in the sequence 1,2,6,15,31,56,91


(a) 15
(b) 6
(c) 56
(d) 91

Answer: d


5. If (26)2 is subtract from square of a number, the answer so obtained is 549. What is the number ?


(a) 35

(b) 33

(c) 29

(d) 41

(e) None of these


Answer: a


6. A man is facing south. He turns 90o in the clockwise direction and then 135o in the same direction. Which direction is he facing now?


(a) North-East
(b) North-West
(c) South-East
(d) South-West


Answer: a


7. [(4)3 x (5)4 ] ÷ (4)5 = ?


(a) 30.0925

(b) 39.0625

(c) 35.6015

(d) 29.0825

(e) None of these


Answer: b


8. (8.2% 365) – (1.75% of 108) = ?

(a) 16.02 (b) 28.04 (c) 42.34 (d) 53.76 (e) None of these




9. (739% of 383) ÷ 628 ? ?


(a) 10.00

(b) 4.50

(c) 15.75

(d) 19.25

(e) 24.15


Answer: b


10. 94.5% of 550 = ?


(a) 506.45

(b) 521.65

(c) 518.55

(d) 519.75

(e) None of these


Answer: d


11.  ………….. is the part of the computer that does the arithmetical calculations.


(a) Memory

(b) OS

(c) CPU

(d) ALU

(e) None of these




12. A rectangular park 60 m long and 40 m wide has two concrete crossroads running in the middle of the park and rest of the park has been used as a lawn. If the area of the lawn is 2109 sq. m, then what is the width of the road?


(a) 3 m
(b) 2.91 m
(c) 5.82 m
(d) None of these


Answer: a


13. The CPU, also called the …………… when talking about Pcs, does the vast majority of the processing for a computer.


(a) macroprocessor

(b) RAM

(c) Memory System

(d) microprocessor

(e) None of these




14. Two pipes A and B can fill a cistern in 37 1/2 minutes and 45 minutes respectively. Both pipes are opened. The cistern will be filled in just half an hour, if the B is turned off after:


(a) 5 min
(b) 10 min
(c) 9 min
(d) 15 min

Answer: c


15. A computer’s type, processor, and operating system define its.


(a) brand

(b) size

(c) platform

(d) speed

(e) None of these


Answer: d


16. The part of the Central processing unit (CPU) that accesses and decodes program instructions and coordinates the flow of data among various system components is the


(a) ALU

(b) control unit

(c) megahertz

(d) motherboard

(e) None of these


Answer: b


17. What is the difference between a CD-ROM (Read Only Memory) and a CD-RW?


(a) They are the same-just two different terms used by different manufacturers.

(b) A CD-ROM can be written to and a CD-RW cannot

(c) A CD-RW can be written to, but a CD-ROM can only be read from

(d) A CD-ROM holds more information than a CD-RW.

(e) None of these


Answer: c


18. When a product is sold at certain price, it gives 20% gain. What is the gain when it is sold at thrice the price ?


(a) 250
(b) 260
(c) 270
(d) 280

Answer: b


19. Find the next number in the sequence 1,2,4,7,11,___


(a) 15
(b) 18
(c) 16
(d) 12

Answer: c


20. A disk’s content that is recorded at the time of manufacture and that cannot be changed or erased by the user is-


(a) memory-only

(b) write-only

(c) read-only

(d) run-only

(e) None of these


Answer: c


21.The sum of two digit number and its reverse number is 99. How many such numbers are possible ?


(a) 9
(b) 10
(c) 16
(d) 100

Answer: b


22. What is the least number to be added to 3986 to make it  a perfect square ?


(a) 118

(b) 95

(c) 110

(d) 100

(e) None of these

Answer: c


23. 137% of 12345? ?


(a) 17000

(b) 15000

(c) 1500

(d) 14300

(e) 900


Answer: a


24. The average weight of two groups consisting of 70 and 30 members are 70 and 30 respectively. What is the total average weight ?


(a) 61
(b) 58
(c) 49
(d) 52

Answer: b


2. Technical questions


a) Electronics and Electrical questions

The HAL Electronics and Electrical written test is an online test, in which objective type of questions are asked with a time limit of mostly 2 ½ hours.Here are a few questions asked in the Electronics and Electrical section of HAL written test:


1. The function of pole shoes in the case of D.C. machine is


(a) to reduce the reluctance of the magnetic path
(b) to spread out the flux to achieve uniform flux density
(c) to support the field coil
(d) to discharge all the above functions

2. In the case of lap winding resultant pitch is


(a) multiplication of front and back pitches
(b) division of front pitch by back pitch
(c) sum of front and back pitches
(d) difference of front and back pitches

3. In D.C. generators, the cause of rapid brush wear may be


(a) imperfect contact
(b) rough commutator surface
(c) severe sparking 
(d) any of the above

4. In lap winding, how many numbers of brushes are used always?


(a) two
(b) same as the number of poles
(c) half the number of poles
(d) double the number of poles

5. What are Laminations of core are made of generally?
(a) carbon 
(b) silicon steel
(c) cast iron
(d) stainless steel


6. For a D.C. generator when the number of poles and the number of armature conductors is fixed, then which winding will give the higher e.m.f.?


(a) Wave winding 
(b) Lap winding
(c) Either of (a) and (b) above
(d) Depends on other features of design

7. Which of the following could be lamina-proximately the thickness of laminations of a D.C. machine?


(a) 5 m
(b) 0.05 mm
(c) 0.5 m
(d) 0.005 mm


8. Why are Copper brushes in D.C. machine used?


(a) where low voltage and high currents are involved
(b) where high voltage and small cur-rents are involved
(c) in both of the above cases
(d) in none of the above cases

9. How is a separately excited generator as compared to a self-excited generator better?


(a) is amenable to better voltage control
(b) is more stable
(c) has exciting current independent of load current
(d) has all above features

10. Why is the armature of D.C. generator laminated?


(a) provide the bulk
(b) reduce the bulk
(c) insulate the core
(d) reduce eddy current loss

11. On what does the resistance of armature winding depends?


(a) cross-sectional area of the conductor 
(b) length of conductor
(c) number of conductors
(d) all of the above

12. What are the field coils of D.C. generator usually made of?


(a) Copper
(b) Mica
(c) Cast iron 
(d) Carbon

13. The commutator segments are connected to the armature conductors by means of


(a) resistance wires
(b) copper lugs 
(c) insulation pads
(d) brazing

14.In a commutator, what is harder


(a) copper is harder than mica
(b) mica and copper are equally hard
(c) mica is harder than copper
(d) none of the above

15. In D.C. generators how are the pole shoes are fastened to the pole core by


(a) brazing 
(b) counter sunk screws
(c) rivets
(d) welding

16. According to Fleming's right-hand rule for finding the direction of induced e.m.f., when middle finger points in the direction of induced e.m.f., forefinger will point in the direction of


(a) lines of force
(b) motion of conductor
(c) either of the above
(d) none of the above


17. What is the material used in commutator brushes?


(a) carbon 
(b) copper
(c) cast iron 
(d) Mica

18. What is the insulating material used between the commutator segment is?


(a) Graphite 
(b) mica
(c) paper 
(d) insulating varnish

19. What does the Fleming's right-hand rule regarding direction of induced e.m.f correlates to


(a) magnetic field strength, induced voltage and current
(b) magnetic flux, direction of motion and the direction of e.m.f. induced
(c) magnetic flux, direction of current flow and resultant force
(d) magnetic flux, direction of force and direction of motion of conductor

20. While applying Fleming's right-hand rule to And the direction of induced e.m.f., the thumb points towards


(a) direction of induced e.m.f.
(b) direction of flux
(c) direction of motion of the conductor if forefinger points in the direction of generated e.m.f.
(d) direction of motion of conductor, if forefinger points along the lines of flux

21. In a four-pole D.C. machine


(a) all the four poles are north poles
(b) alternate poles are north and south
(c) two north poles follow two south poles
(d) all the four poles are south poles

22. In case of D.C. machines, mechanical losses are primary function of


(a) speed 
(b) voltage
(c) current
(d) friction

23. What are the Brushes of D.C. machines made of?


(a) soft copper
(b) carbon
(c) hard copper 
(d) all of above

24. If B is the flux density, I the length of conductor and v the velocity of conductor, then induced e.m.f. is given by



25. In case of a 4-pole D.C. generator provided with a two layer lap winding with sixteen coils, the pole pitch will be


(a) 8 
(b) 4
(c) 32
(d) 16

26. In D.C. generators, the brushes on commutator remain in contact with conductors which


(a) lie under south pole
(b) lie under north pole
(c) are farthest from the poles
(d) lie under interpolar region

27. Which of the following statement about D.C. generators is false ?


(a) Compensating winding in a D.C. machine helps in commutation
(b) In a D. C. generator interpoles winding is connected in series with the armature winding
(c) Back pitch and front pitch are both odd and approximately equal to the pole pitch
(d) Equilizing bus bars are used with parallel running of D.C. shunt generators


28. In a D.C. generator, how are the ripples in the direct e.m.f. generated reduced by?


(a) using conductor of annealed copper
(b) using commutator with large number of segments
(c) using carbon brushes of superior quality
(d) using equiliser rings

29. Magnetic field in a D.C. generator is produced by


(a) electromagnets
(b) permanent magnets
(c) both (a) and (b)
(d) none of the above

30. On what does the number of brushes in a commutator depends on?


(a) speed of armature
(b) voltage 
(c) type of winding 
(d) amount of current to be collected


b) Current Affairs Question

Here are a few questions asked in the HAL written test of current affairs:

1. Who was the Miss World 2013?


(a) Megan Young 

(b) Marine Lorphelin
(c) Naa Okailey
(d) Laura Jane Corker


2. Who had discovered oxygen?

(a) Carl Scheele and Joseph Priestley
(b) Carl Scheele and Charles Babbage
(c) Charles Babbage

(d) Benjamin Franklin

3. How many Major Mountain Ranges in India?

(a) 7
(b) 8
(c) 5
(d) 9

4. Which automobile company became first automaker to participate in Greenhouse Gas Reporting Programme in India on 23 July 2013?

(a) Ford Motor Company
(b) General Motors
(c) Maruti Suzuki
(d) Mahindra and Mahindra Limited


5. When was battle of Plessey fought? 

(a) 1757
(b) 1751

(c) 1752
(d) 1758

6. What does Ophidiophobia means?


(a) Fear of Height
(b) Fear of water
(c) Fear of snakes
(d) Fear of darkness

7. Which country won the first Fifa world cup?

(a) Spain 
(b) Germany 
(c) France

(d) England

8. Who has written the autobiography "my life".


(a) Bill Clinton

(b) Queen Elizabeth
(c) Prince Charles

(d) Barack Obama


9. Who is the Winner of Saraswati Samman Award 2013?


(a) Sugathakumari

(b) Rani Jaisingh
(c) Palashi Yuddha
(d) Rani Sugatha

10. According to the recent satellite images, deforestation has dropped down by around one-third since 2000 in which rainforests of Africa?


(a) Congo Basin

(b) Zaire Basin
(c) Amazon Rainforest

(d) Tropical Region

11. INSAT-3D was launched successfully by the European rocket from the spaceport of Kourou in French Guiana on 26 July 2013. What is the purpose of INSAT-3D?


(a) To provide technological experience in building and operating a satellite system
(b) To provide experience in building and operating a payload experiment three-axis stabilised communication satellite
(c) For multipurpose communication: business communication, developmental communication, and mobile communication
(d) Meteorological Satellite with advanced weather monitoring payloads

12. In Olympics when did India won first ever gold medal?


(a) 1920
(b) 1900

(c) 1925
(d) 1921

13. The Supreme Court of India on 24 July 2013 slapped contempt notices on two Sahara firms for not complying with its order of refunding around 19000 crore rupees to investors. Which body filed the contempt petition against Sahara firms?


(a) Pension Fund Regulatory and Development Aulthority (PFRDA)
(b) The Insurance Regulatory and Development Authority (IRDA)
(d) Securities and Exchange Board of India (SEBI)
(e) Forward Markets Commission (FMC)

14. What is the technical name of Northern Lights?


(a) Aurora borealis

(b) Geometric Storm
(c) Solar Wind
(d) Substorm


15. What are Uber Cup, sudiman Cup tournaments are related to?


(a) Cricket
(b) Badminton.
(c) Hockey
(d) Football

16. Tallinn is a capital city of.
(a) Romania
(b) Estonia

(c) Gaza
(d) Lithuania

17. Zend Avesta is a holy book of which religion?


(a) Buddhism 
(b) Scientology 
(c) Zoroastrianism 
(d) Jainism

18. Who is the painter of the Famous painting "sun flower" ?

(a) Edgar Degas
(b) Vincent van Gogh
(c) Edward Munch
(d) Frida Kahlo


19. The President of India, Pranab Mukherjee inaugurated the first?


(a) First Engineers Conclave-2013 on 17 September 2013
(b) First Engineers Conclave-2013 on 17 October 2013
(c) First Engineers Conclave-2013 on 17 December 2013
(d) First Engineers Conclave-2013 on 17 March 2013

20. Which of these are associated with cricket stadium or ground?
(a) Pavilion end
(b) Nursery end
(c) St. Johns Road

(d) End Road

c) Chemical Engineering Questions

Here are few questions asked in the HAL written test of Chemical Engineering section. 


1. How is Bleaching of paper pulp done?

(a) bromine
(b) activated clay
(c) chlorine or chlorine dioxide 
(d) magnesium sulphite

2. Why is Plasticisers added to paints?

(a) make it corrosion resistant.
(b) give elasticity & prevent cracking of the film. 
(c) increase atmospheric oxidation.
(d) make glossy surface

3. What is the function of thinner in paint?

(a) accelerate the oxidation of oil.
(b) prevent gelling of the paint. 
(c) from a protective film.
(d) suspend pigments & dissolve film forming materials.


4. From the following which is a high grade pulp?

(a) Sulphate pulp
(b) Mechanical pulp
(c) Rag pulp 
(d) Sulphite pulp

5. Why are enamels used?

(a) are same as varnish. 
(b) give good glossy finish.
(c) are prepared from non-drying oil.
(d) do not contain pigment.

6. What does Bond crushing law states?

(a) calls for relatively less energy for the smaller product particles, than does the Rittinger law. 
(b) is less realistic in estimating the power requirements of commercial crushers.
(c) state that the work required to form particle of any size from very large feed is proportional to the square root of the volume to surface ratio of the product.
(d) states that the work required for the crushing is proportional to the new surface created.

7. What varnish does not contain?

(a) anti-skimming agent. 
(b) thinner
(c) dryer
(d) pigment

8. Which of the following is the starting material for the production of Molasses?

(a) massecuite 
(b) essential oil
(c) fatty acids
(d) Alcohol

9. What is the Shape factor for a cylinder whose length equals its diameter?

(a) 1.0
(b) 0.5
(c) 1.5
(d) 2.0

10. What is the ratio of the actual mesh dimension of Taylor series to that of the next smaller screen?

(a) 1
(b) v2 
(c) 1.5
(d) 3

11. What is the opening of a 200 mesh screen Taylor series?

(a) 0.0047 cm 
(b) 0.0074 mm
(c) 0.0074 cm 
(d) 74 mili-microns

12. What is the ratio of the area of openings in one screen to that of the openings in the next smaller screen?

(a) 1.5
(b) 1
(c) 1.7
(d) none of these 


13. What is the enzyme which converts starch into the disaccharides maltose?

(a) yeast 
(b) maltase
(c) diastase
(d) none of these

14. The equivalent diameter of a particle is the diameter of the sphere having the same

(a) ratio of surface to volume as the actual volume. 
(b) ratio of volume to surface as the particle.
(c) volume as the particle.
(d) none of these

15. What is used for the coarse reduction of hard solids?

(a) compression 
(b) attrition
(c) impact 
(d) cutting

16. What is made of Soft & non-abrasive materials into fines?

(a) attrition 
(b) compression
(c) cutting
(d) none of these


17. What is Cooking liquor in case of sulphite process?

(a) sodium sulphite and sodium bisulphite. 
(b) magnesium sulphite and free SO2 in acid medium.
(c) magnesium sulphate and magnessium bicarbonate.
(d) none of these

18. What is the ratio of Crushing efficiency?

(a) surface energy created by crushing to the energy absorbed by the solid.
(b) energy absorbed by the solid to that fed to the machine.
(c) energy created by crushing.
(d) energy absorbed by the solid to the surface energy created by crushing.

19. What does the Rittinger's crushing law states?

(a) work required to form a particle of any size is proportional to the square of the surface to volume ratio of the product.
(b) work required to form a particle of a particular size is proportional to the square root of the surface to volume ratio of the product.
(c) work required in crushing is proportional to the new surface created. 
(d) for a given machine and feed, crushing efficiency is dependent on the size of the feed & product.


20. Why is SO2 bubbled through hot sugar cane juice?

(a) increase the crystal size. 
(b) increase its concentration.
(c) increase the amount of molasses. 
(d) act as an acidifying agent.

21. How does work index defined?

(a) gross energy (k Wh/ton of feed) needed to reduce very large feed to such a size that 80% of the product passes through a 100 micron screen. 
(b) energy needed to crush one tonne of feed to 200 microns.
(c) energy (k Wh/ton of feed) needed to crush small feed to such a size that 80% of the product passes a 200 mesh screen.
(d) energy needed to crush one ton of feed to 100 microns.


22. Which oil is preferred for manufacturing paint?

(a) Saturated oil 
(b) Non-drying oil
(c) Semi-drying oil
(d) Drying oil

23. What is a fluid energy mill used for?

(a) cutting
(b) grinding
(c) ultragrinding 
(d) crushing


24. The Cumulative analysis for determining surface is more precise than differential analysis, because of the

(a) assumption that all particles in a single fraction are equal in size.
(b) fact that screening is more effective.
(c) assumption that all particles in a single fraction are equal in size.
(d) assumption that all particles in a single fraction are equal in size, is not needed.

25. The ideal pulp for the manufacture of paper should have high content of which material?
(a) ellulose 
(b) lignin
(c) Lignin and ellulose
(d) none of these

26. Comparing sulphate process with sulphite process, what do we find in the later.

(a) both temperature & pressure in the former is less than that
(b) both temperature & pressure in the former is more than that 
(c) temperature is more in the former whereas pressure is more
(d) pressure is more in the former whereas temperature is less


27. What does Wet grinding in a revolving mill do as compared to dry grinding?

(a) gives less wear on chamber walls
(b) requires more energy
(c) increases capacity 
(d) decreses handling of the product


28. The operating speed of a ball mill should be ......... the critical speed.

(a) much more than 
(b) less than
(c) at least equal to
(d) slightly more than

29. During manufacturing which of the following paper does not require filler?

(a) Blotting paper
(b) Writing paper
(c) Bond paper 
(d) Coloured paper


30. White cooking liquor consists of caustic soda, in Kraft process of paper manufacture

(a) sodium sulphide & sodium carbonate. 
(b) sodium sulphite & sodium carbonate.
(c) sodium sulphite & sodium sulphide.
(d) All of the three


d) Computer Science Questions

Here are few questions asked in the HAL written test of Computer Science Engineering section. 

1. Which is the most significant difference between a simple desk calculator and computer? Choose from the following (note that some of the following may not even be true). 

(a) One has to know the method of calculation while using a calculator but a computer user can depend upon the computer to choose the method automatically. 
(b) the computer is useful in business applications while the desk calculator is not 
(c) the computer can print its results, while the desk calculator can only show it on a display 
(d) the computer is controlled by a program stored in its memory while calculator require step-by-step manual control 

2. Why is RAM used as a short memory?

(a) is volatile 
(b) is very expensive 
(c) has small capacity 
(d) None of the above

3. A computer derives its basic strength from 

(a) speed 
(b) accuracy
(c) memory 
(d) all of the above 

4. A term associated with the comparison of processing speeds of different computer systems is : 

(a) MIPS
(b) MPG 
(c) EFTS 
(d) CPS

5. The use of computer for business applications is attractive because of its 

(a) accuracy 
(b) reliability 
(c) speed 
(d) All of the above 


6. Modern computers compared to earlier computers are 

(a) faster and smaller
(b) less reliable 
(c) larger and stronger 
(d) slower but more reliable

7. A computer is capable of performing almost any task, provided that it can be 

(a) reduced to a series of logical steps
(b) memorized 
(c) analyzed 
(d) coded


8. Pick up the false statement 

(a) the space in the primary storage section is divided into four areas: input, working, storage, output and program storage.
(b) computer errors can usually be traced to faulty programs or inaccurate input data 
(c) the facts or informational raw materials represented by numeric and non-numeric symbols are called information 
(d) computer can manipulate both numeric and non-numeric symbols

9. A computer has very high speed, accuracy and reliability. Its intelligence quotient could be of the order of 

(a) 0
(b) 01 
(c) 50
(d) 200

10. A Computer can not do anything without?

(a) program 
(b) memory
(c) output device 
(d) chip

11. How does a computer possess information? 

(a) as directed by the operator 
(b) gradually
(c) at once 
(d) automatically

12. What does the processors of all computers, whether micro, mini or mainframe has?

(a) Control Unit 
(b) primary storage 
(c) ALU
(d) all of the above 

13. What is a correct statement about computers 

(a) Computers have the built-in ability to obey different types of instructions. 
(b) all comparisons are made in the control section 
(c) the arithmetic-logic section of the CPU selects, interprets and executes the program steps. 
(d) the secondary storage devices are usually connected on line to the CPU but for accepting data from them or returning data to them, human intervention is required 

14. Real time computing is possible because of the following characteristic of computer 

(a) storage capability 
(b) high speed 
(c) automatic in execution
(d) versatility 

15. What is not true about modern computer systems 

(a) these are simple and easy to take care of 
(b) even beginners, untrained persons can safely handle them 
(c) they require a highly disciplined approach 
(d) the negligent use of a computer system will almost always introduce time bombs into the system. 


17. What is false about microcomputers, mini-computers, etc.? 

(a) most micros use rigid disk storage devices rather than floppy disk drives
(b) a minicomputer can have more processing capability than a mainframe model 
(c) a microcomputer chip performs the arithmetic-logic and control functions of a microcomputer 
(d) ROM chips may be used in micros; to permanently store program instruction 

18. What does a collection of eight bits called? 

(a) byte 
(b) word 
(c) record 
(d) file 

19. What does a group of instructions that directs a computer called ?

(a) storage 
(b) memory 
(c) logic 
(d) None of the above


20. What does BIT represents? 

(a) binary digit 
(b) octal digit 
(c) decimal digit 
(d) hexa decimal digit 

21. Which of the following does not describe one or more characteristics of a computer?

(a) electronic 
(b) external storage 
(c) program modification at execution
(d) All of the above are characteristics. 

22. What is the general purpose of computers that can be adapted to countless uses simply by changing its? 

(a) keyboard 
(b) program 
(c) printer 
(d) None of the above

23. Which is the computer memory that does not forget?

(a) RAM 
(b) ROM
(c) PROM 
(d) None of the above 

24. Why is the Santa Clara Valley near Palo Alto, California popularly known as Silicon Valley of America?

(a) huge deposits of silicon are found there 
(b) many silicon chip manufacturing firms are located there 
(c) it is full of large grain sand
(d) Santa Claus visits it every Christmas

25. Computers are incapable of emotional feelings. However, some people attribute humanlike emotions to imitate objects including computers. What is it called?

(a) anthropogenesis 
(b) anthropomorphism 
(c) anthroolatory 
(d) cybernetics 

26. The most common binary code in use today is the 8 bit ASCII code. What do the letters ASCII stand for?

(a) American Scientific Code for Information Interchange 
(b) American Standard Code for Information Interchange 
(c) American Standard Code for Intelligence interchange 
(d) None of the 


27. In order to trace the incorrect input data or unreliable programs this of the following acronym recognizes the fact that “computer errors?" 

(a) IGO 
(b) ROM
(c) LIFO
(d) DASD

28. What is the Control Unit of a digital computer called? 
(a) Lock 
(b) Nerve centre 
(c) ICs 
(d) None of the above