# Aircraft Instrumentation MCQ (Multiple Choice Questions)

1. Which of the following is not the type of Quantitative Displays?
a) Circular Displays
b) Straight Displays
c) Digital or Counter Displays
d) Synchronous Displays

Explanation: Synchronous Displays are Qualitative Displays, whereas Circular Displays, Straight Displays and Digital or Counter Displays are Quantitative Displays.

2. The sequence of numbering always increases in a clockwise direction in case of Circular Displays.
a) True
b) False

Explanation: Because of the Visual Expectations of an observer, sequence of numbering always increases in a clockwise direction in case of Circular Displays.

3. Digital or Counter Displays are technically termed as ______
a) Alpha-Numeric Displays
b) Pictorial Displays
c) Pitot Static Displays
d) Alphabetic Displays

Explanation: Digital or Counter Displays present the given data in terms of Alphabets and Numbers, therefore they are known as Alpha-Numeric Displays whereas Pictorial Displays indicate data in Symbolic form and Pitot-Static Displays are used to get value of pressure which is used further to get value of Speed and Altitude.

4. Which of the following Display contributes to saving Panel Space?
a) Digital Displays
b) Straight and Circular Displays
c) Synchronous Displays
d) Counter Displays

Explanation: Straight and Circular Displays improve Observational Accuracy and these Displays are easy to group with other indicators which results in saving the Panel Space, whereas Digital Displays or Counters and Synchronous Displays have some electric circuit associated with them, so they require more space on the instrument panel.

5. Which of the following Scale is used to indicate various Engine related quantities?
a) Circular Displays
b) Straight Displays
c) Dual-Indicator Displays
d) Counter Displays

Explanation: Because of Dual Displays in Dual-Indicator Displays, it is easy to indicate the amount of Fuel and Oil in single Display instead of using separate displays for both quantities.

6. What does the Red Radial Line indicate in Coloured Displays?
a) Maximum and Minimum Limits
b) Take-Off Precautionary Range
c) Normal Operating Range
d) Operation Prohibited Range

Explanation: Red Radial Line indicates Maximum and Minimum Limits, whereas Green arc indicates Normal Operating Range and Red arcs indicates Operation Prohibited Range.

7. Which of the following indicates Take-Off Precautionary Range?
b) Yellow Arc
c) Green Arc
d) Red Arc

Explanation: Take-Off Precautionary Range is indicated by Yellow Arc. In this range, Airspeed Turbulence is not high, whereas Red Radial Line indicates range of speeds, Green arc indicates operating range and Red arcs indicates Operational Prohibited Range.

8. Airspeed Indicator Dials don’t have White Arc.
a) True
b) False

Explanation: White Arc on the Airspeed Indicator indicates Airspeed Range over which Landing Flaps can be extended during landing and take-off.

9. Which of the following Display is referred in the following diagram?

a) Straight Display
b) Circular Display
c) Digital Display
d) Counter Display

Explanation: Straight Displays are linear. They can be Vertical or Horizontal, whereas Circular Displays are not Linear. Digital and Counter Displays represent data in digital formats.

10. Quantitative Displays represent data in _____
a) Pictorial Form
b) Symbolic Form
c) Audio Form
d) Numeric Form

Explanation: Quantitative Displays represent data in Numeric Form, whereas Qualitative Displays represent data in Symbolic and Pictorial Forms.

11. The following diagram indicates which type of indicator?

a) Straight Display
b) Circular Display
c) Dual Indicator Display
d) Digital Display

Explanation: Diagram consists of Display having two indicators for two different quantities. Such Displays are known as Dual Indicator Displays.

## Aircraft Instrumentation MCQ on Qualitative Displays

12. The information is presented in Pictorial and Symbolic forms in case of Qualitative Displays.
a) True
b) False

Explanation: Qualitative Displays are special types of Displays which represent data in the form of Symbols and Pictures, whereas in Quantitative Display, data is presented in Numeric form, which is also known as Alpha-Numeric Displays.

13. Which of the following is an example of Qualitative Display?
a) Straight Displays
b) Digital Displays
c) Synchroscope
d) Circular Displays

Explanation: The Synchroscope Display represents Propeller Speed in which its pointers symbolize the Propellers, as we know Qualitative Displays represent data in Symbolic Form.

14. The ILS is an abbreviation of ______
c) Instrument Landing System

Explanation: The ILS stands for Instrument Landing System which is implemented during Aircraft Landing along with Flight Director and Integrated Instrument System, which acts as a localizer for an aircraft during landing.

15. Which of the following mechanism does not belong to Rod-Mechanisms?
a) Sine-Mechanism
b) Tangent-Mechanism
c) Double-Tangent-Mechanism
d) Lever-Angle-Magnification

Explanation: Lever-Angle-Magnification is considered Lever-Mechanism, whereas Sine, Tangent and Double-Tangent-Mechanism are Rod-Mechanism.

16. Angle of Observation affects the Instrument Reading.
a) True
b) False

Explanation: Although the Instrument Reading may be accurate, but observing that reading at different angles makes it inaccurate as it may give rise to Parallax Error. If user observes reading at some angle to perpendicular plane, then instead of accurate reading he may observe reading adjacent to the original one.

17. In Straight Scale, what does each Display Unit contain in place of Pointer?
a) Mercury
b) Triple Pointer
c) Servo-Driven White Tape
d) Magnetic-Needle

Explanation: Each Display Unit contains Servo-Driven White Tape in place of pointer in Straight Scale, because it rotates in vertical plane and indicates reading.

18. The Counter Display linked with Altimeter which automatically measures data is known as Static Counter Display.
a) True
b) False

Explanation: The Counter Display which measure data automatically is known as Dynamic Counter Display which is linked with Altimeter. In case of Static Counter Display, pressure data is mechanically set by pilot.

19. The Counter of TGT Indicator is driven by _____
a) Servo Transmission
b) Manual Transmission
c) Continuously Variable Transmission
Explanation: The Counter of TGT Indicator is driven by Servo-Transmission. Servo Transmission is automated and Counter of TGT Indicator is Dynamic as dynamic counters use an automated transmission. So, TGT Indicator Counter is driven by Servo Transmission.

20. The Alpha-Numeric Displays are also known as _____
a) Straight Display
b) Circular Display
c) Synchronous
d) Veeder-Counter

Explanation: Alpha-Numeric Counters are known as Veeder-Counters, because these types of Counters are mainly manufactured by Veeder-Root Company. As being the lead manufacturer, these Displays are also known by the name of their manufacturing company.

21. Pictorial representation offered by Qualitative Displays is further improved by painting of _____
a) Qualitative Lines
b) Flow Lines
c) Quantitative Lines
d) Computational Lines

Explanation: Flow Lines interconnect the System Switches and Indicators that’s why Pictorial representation offered by Qualitative Displays is improved by painting of Flow Lines.

22. In aircraft, Instrument Panels are sloped at how much angle with the vertical?
a) 15 Degrees
b) 30 Degrees
c) 45 Degrees
d) 60 Degrees

Explanation: To avoid errors in reading of Instruments caused by the Angle of Observation factor, Instruments Panels are sloped at 15 Degrees with the vertical to overcome Parallax Errors, in which if an observer observes instrument at an angle, he may get incorrect reading which is corrected by sloping instrument panel.

## Aircraft Instrumentation MCQ on High-Range Long Scale Displays

23. For Lengthy Scales which of the following Display is preferred?
a) Circular Display
b) Counter Display
c) Concentric Circular Display
d) Synchroscope Display

Explanation: For Lengthy Scales, it’s difficult to indicate reading as reading is very high and for accuracy, we need High Range Scale, so we use Concentric Circular Displays in which inner and outer indicator are continuous which provides Long Range of values.

24. Which of the following is not the type of High-Range-Long-Scale Displays?
a) Concentric Scales
b) Fixed and Rotating Scales
c) Common Triple Pointer Scales
d) Normal Circular Scale

Explanation: Normal Circular Scale is used for low-medium range readings, But for Long-Range reading we use Concentric, Fixed and Rotating, Common Triple Pointer Scales.

25. Can we consider the following Display as High-Range-Long Scale Display?

a) True
b) False

Explanation: Because this Display consists of two Circular Displays which increases its Range of Readings. It is converted to High Scale Circular Display from Simple Circular Display. Initially we were having only one pointer, now it has two pointers to indicate larger readings.

26. Length of Circular Instrument Scale can exceed the Operating Range of instrument.
a) True
b) False

Explanation: If the length of an Instrument Scale exceeds Operating Range, firstly we think that the length other than operating range is wasteful, but it’s not, as increment in length of circular scale decreases gap between two consecutive divisions which increases the accuracy.

27. In Straight Scale, Numbering Sequence is from _____
a) Right to Left
b) Left to Right
c) Clockwise
d) Anti-Clockwise

Explanation: Because of the Visual Expectations of an observer, numbering sequence is from Left to Right in Straight Scale, which makes it easier for an observer to take readings.

28. Which type of Error occurs while observing Indicator Displays at an angle?
a) Parallax Error
b) Tangent Error
c) Qualitative Error
d) Quantitative Error

Explanation: While observing Indicator Displays at an angle, it arises Parallax Error which means if we do not observe the pointer perpendicular to its plane then because of some angle of elevation or depression, we can see pointer at some different reading, which may be adjacent to the actual reading.

29. In Triple Hydraulic System, which of the following Coloured Display is not used?
a) Yellow
b) Green
c) Blue
d) Brown

Explanation: Brown Coloured Display is not used in Triple Hydraulic System. Yellow, Green and Blue colours are used to identify Pressure Indicator Systems in each Systems.

30. Which of the following Engine uses Synchroscope Indicators?
a) Propeller Engine
b) Piston Engine
c) Jet Engine
d) Turbo Jet Engine

Explanation: Synchroscope Indicator measures the Propeller Speed in symbolic form as it is Qualitative Display. To measure Propeller Speed, engine must be Propeller Engine or any engine having Propeller as thrust generator.

31. The application of Triple Pointer Display is mainly confined to _____
a) Speedometer
b) Altimeter
c) Pressure Indicator
d) Turn and Bank Indicator

Explanation: Triple Pointer Display is High-Range Long-Scale Display. So, it is used to measure higher values of altitude conveniently that’s why it is used in Altimeter, for Speedometer Dual Pointer Display is enough, for Turn and Bank Indicator single pointer pointed at both the edges is used and in case Pressure Indicator we use Pitot Static Tube.

32. Fixed and Rotating Scales and Split Pointers are generally used in _____
a) Pressure Indicator
b) Altimeter
c) Speed Indicator
d) Pitot Static Tube

Explanation: Being High-Range Long-Scale Displays, Fixed and Rotating Scales and Split Pointers are used in indication of Speed, in which two displays are adopted with only single scale.

More MCQs on Aircraft Instrumentation:

If you find a mistake in question / option / answer, kindly take a screenshot and email to [email protected]