Fill in the Blanks
1. a. absolute, b. gauge, c. differential
2. 29.92, 14.7
3. gauge
4. Bourdon
5. a. pitot, b. static
6. engine pressure ratio
7. altimeter
8. indicated
9. mean sea level
10. inches, mercury (Hg), millibars
11. pressure
12. 32,000
13. temperature
14. position
15. 91.411
16. 24
17. indicated
18. Machmeter
19. 0.95
20. vertical speed
21. Wheatstone bridge, ratiometer
22. thermocouple
23. accelerometer (G-meter)
24. synchroscope 25. tachometer
True or False
2. 29.92, 14.7
3. gauge
4. Bourdon
5. a. pitot, b. static
6. engine pressure ratio
7. altimeter
8. indicated
9. mean sea level
10. inches, mercury (Hg), millibars
11. pressure
12. 32,000
13. temperature
14. position
15. 91.411
16. 24
17. indicated
18. Machmeter
19. 0.95
20. vertical speed
21. Wheatstone bridge, ratiometer
22. thermocouple
23. accelerometer (G-meter)
24. synchroscope 25. tachometer
True or False
1. false
2. true
3. true
4. false
5. false
6. true
7. false
8. false
9. true
10. true
11. false
12. true
13. false
14. false
15. false
Knowledge Application
2. true
3. true
4. false
5. false
6. true
7. false
8. false
9. true
10. true
11. false
12. true
13. false
14. false
15. false
Knowledge Application
1. The airspeed indicator, the vertical speed indicator, and the altimeter.
2. None. All repairs and alterations must be made by the instrument manufacturer or by an FAA-approved repair station certificated for the particular instrument.
3. A red radial line marks a never-exceed condition.
4. A yellow arc marks a caution range of operation.
5. A green arc indicates the normal range of operation.
6. A white arc on an airspeed indicator indicates the airspeeds at which the flaps may be lowered.
7. A white slippage mark that extends across the lower part of the instrument cover glass and the instrument case bezel shows whether or not the glass has slipped. A slipped glass would put the range marks over the incorrect numbers.
8. In the Type Certificate Data Sheets for the aircraft.
9. The static system must be checked for leaks.
10. A steel case concentrates the flux produced by magnets in the instrument and keeps it from affecting other nearby instruments.
11. The bonding straps carry the return current from the instruments into the aircraft structure.
12. Deviation error.
13. A special water-clear fluid that is similar to kerosine.
14. 10 degrees.
15. For an unpressurized aircraft, the system is checked with a 1,000-foot indication on the altimeter. It must not leak more than 100 feet in one minute. For a pressurized aircraft, the system is checked at the maximum certificated pressure differential of the cabin. It must not leak, in one minute, more than 2% of the equivalent altitude of the maximum differential pressure or 100 feet, whichever is greater.
Multiple Choices
1. b
An aircraft's magnetic compass is swung to correct for magnetic disturbances within the aircraft, called deviation.
2. a
A hydraulic pressure gage generally uses a Bourdon tube and a gear-and-pinion mechanism by which the Bourdon tube's motion is amplified and transferred to the pointer.
3. b
The fixed reference marker attached to the compass bowl of a magnetic compass is called a lubber line.
4. a
Instrument range markings indicate at a glance whether a system or component is operating in a safe range or an unsafe range. See also FAR 23.
5. c
A compensating device containing small permanent magnets is incorporated in the compass to correct for deviations of the compass which result from the magnetic influences of the aircraft structure and electrical system.
6. b
An aircraft's altimeter and airspeed indicator rely on the static pressure reading to accurately indicate their readings. The altimeter displays altitude as a function of outside (ambient) pressure, a reading which comes from the static system. The airspeed indicator displays a reading by comparing the total pressure in the pitot system to the static pressure reading. If the static pressure value being supplied to both of these systems is coming from a pressurized cabin, it will cause the altimeter and the airspeed indicator to both read low.
7. a
According to FAR 23, the maximum deviation (during level flight) permitted in a magnetic direction indicator installed in an airplane is 10.
8. a
The magnetic compass consists of a liquid filled bowl containing a pivoted float element to which one or more bar magnets, called needles, are fastened. The liquid in the bowl dampens the oscillations of the float and decreases the friction of the pivot.
9. b
When suction is applied to the static system in an aircraft, the altimeter is made to read a higher altitude (as a function of the decreased pressure). By observing the rate of change (decreasing altitude) in the altimeter, it is possible to check the static system for leakage.
10. b
According to FAR 23, the maximum altitude loss permitted during an unpressurized aircraft instrument static pressure system integrity check is 100 ft in one minute.
OTHER QUESTIONS
2. None. All repairs and alterations must be made by the instrument manufacturer or by an FAA-approved repair station certificated for the particular instrument.
3. A red radial line marks a never-exceed condition.
4. A yellow arc marks a caution range of operation.
5. A green arc indicates the normal range of operation.
6. A white arc on an airspeed indicator indicates the airspeeds at which the flaps may be lowered.
7. A white slippage mark that extends across the lower part of the instrument cover glass and the instrument case bezel shows whether or not the glass has slipped. A slipped glass would put the range marks over the incorrect numbers.
8. In the Type Certificate Data Sheets for the aircraft.
9. The static system must be checked for leaks.
10. A steel case concentrates the flux produced by magnets in the instrument and keeps it from affecting other nearby instruments.
11. The bonding straps carry the return current from the instruments into the aircraft structure.
12. Deviation error.
13. A special water-clear fluid that is similar to kerosine.
14. 10 degrees.
15. For an unpressurized aircraft, the system is checked with a 1,000-foot indication on the altimeter. It must not leak more than 100 feet in one minute. For a pressurized aircraft, the system is checked at the maximum certificated pressure differential of the cabin. It must not leak, in one minute, more than 2% of the equivalent altitude of the maximum differential pressure or 100 feet, whichever is greater.
Multiple Choices
1. b
An aircraft's magnetic compass is swung to correct for magnetic disturbances within the aircraft, called deviation.
2. a
A hydraulic pressure gage generally uses a Bourdon tube and a gear-and-pinion mechanism by which the Bourdon tube's motion is amplified and transferred to the pointer.
3. b
The fixed reference marker attached to the compass bowl of a magnetic compass is called a lubber line.
4. a
Instrument range markings indicate at a glance whether a system or component is operating in a safe range or an unsafe range. See also FAR 23.
5. c
A compensating device containing small permanent magnets is incorporated in the compass to correct for deviations of the compass which result from the magnetic influences of the aircraft structure and electrical system.
6. b
An aircraft's altimeter and airspeed indicator rely on the static pressure reading to accurately indicate their readings. The altimeter displays altitude as a function of outside (ambient) pressure, a reading which comes from the static system. The airspeed indicator displays a reading by comparing the total pressure in the pitot system to the static pressure reading. If the static pressure value being supplied to both of these systems is coming from a pressurized cabin, it will cause the altimeter and the airspeed indicator to both read low.
7. a
According to FAR 23, the maximum deviation (during level flight) permitted in a magnetic direction indicator installed in an airplane is 10.
8. a
The magnetic compass consists of a liquid filled bowl containing a pivoted float element to which one or more bar magnets, called needles, are fastened. The liquid in the bowl dampens the oscillations of the float and decreases the friction of the pivot.
9. b
When suction is applied to the static system in an aircraft, the altimeter is made to read a higher altitude (as a function of the decreased pressure). By observing the rate of change (decreasing altitude) in the altimeter, it is possible to check the static system for leakage.
10. b
According to FAR 23, the maximum altitude loss permitted during an unpressurized aircraft instrument static pressure system integrity check is 100 ft in one minute.
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