1. Lesson 16: Aircraft Instrument Systems

2. Classification Of Instruments
Flight Instruments
Engine Instruments
Auxiliary Instruments

3. Flight Instruments
Those that help visualize the attitude, location and speeds of the aircraft.
Those which indicate the relationship to the air through which we are flying
Those which relate to our position in space without considering the air.

4. Pitot-static System
Dynamic Air Pressure - Pressure caused by moving air.
Ambient Static Air Pressure - Pressure of non-moving air just outside the aircraft.

5. Pitot-static System

6. Pitot Head

7. Pitot Head

8. Flush Static Port

11. Airspeed Indicator
Differential pressure gauge that measures the difference between dynamic and ambient static air pressure.

12. Airspeed Indicator Indicated airspeed
The speed of an aircraft as shown on the airspeed indicator.
True airspeed
The speed at which an aircraft is moving relative to the surrounding air.
Calibrated airspeed
Indicated airspeed of an aircraft, corrected for installation and instrument errors.

13. Altimeter
A barometer that measures the absolute pressure of the air.

14. Altimeter Indicated Altitude
The altitude shown by an altimeter set to current altimeter setting.
Pressure Altitude
Height above the standard pressure level of in.Hg.
Density Altitude
Pressure altitude corrected for nonstandard temperature variations.

15. Altimeter True Altitude
The actual height of an abject above mean sea level.
Absolute Altitude
Actual height above the surface of the earth, either land or water.

16. Vertical Speed Indicator
The rate of climb indicator
Serves only as a backup for the altimeter and airspeed indicator as a pitch indicating instrument.
Helps the pilot establish a rate of climb or descent.

17. Blockage Of The Pitot-Static System
Pitot Tube
Affects only the airspeed indicator, but a clogged static system affects all three pitot-static instruments.
If the pitot tube is blocked and its drain hole remains open, the airspeed reading will drop to zero.
If both pitot tube and the drain hole clog, the airspeed indicator will react like an altimeter.

18. Blockage Of The Pitot-Static System
Static port
The indicated airspeed increases as the airplane descends and decreases when it climbs.
The altimeter: air pressure in the system will not change and neither will your indicated altitude.
VSI continually indicates Zero.

19. Gyroscopic Instruments

20. Gyroscopic Instruments
Turn coordinator
Attitude indicator
Heading indicator

21. Gyroscopic Instruments
Rigidity In Space – Once a gyroscope is spinning, it tends to remain in a fixed position in space and resist external forces applied to it.

22. Gyroscopic Instruments
Precession – The tilting or turning of a gyro in response to pressure.
The reaction to this force occurs in the direction of rotation, approximately 90° ahead of the point where the force was applied.

23. Sources Of Power
Gyroscopes may be operated by electrical power or by a vacuum (suction) system.

24. Sources Of Power

25. Attitude Indicator
Vacuum powered instrument which senses pitching and rolling movements about the airplanes lateral and longitudinal axes.

26. Attitude Indicator

27. Attitude Indicator

28. Directional Gyro
Vacuum powered instrument which senses yaw movement of the airplane about the vertical axis.
Horizontal card directional gyro

29. Directional Gyro
Vertical card directional gyro

30. Rate Gyros
Turn And Slip Indicator
Turn Coordinator
Inclinometer

31. Rate Gyros

32. Turn Coordinator

33. Floating Magnet-type Magnetic Compass

34. Engine Instruments

35. Engine Instruments