Aircraft Instrument Systems Flashcards
The rad radical lines on the face on an engine oil pressure gauge indicates
minimum and/or maximum safe operating limits.
The lubberline on a directional gyro is used to
Represent the nose of the aircraft.
When an aircraft altimeter is set at 29.92” Hg on the ground, the altimeter will read
Pressure altitude
A synchro transmitter is connected to a synchro receiver
Electrically with wires
Magnetic compass bowls are filled with liquid to
Dampen the oscillation of the float.
Aircraft instrument value should be marked and graduated in accordance with
The specific aircraft maintenance of flight manual
Instrument panel shock mounds absorb
Low frequency, high amplitude shocks
The requirements for testing and inspection of instrument static systems required by section 91.411 are contained in
Part43, appendix E
A barometric altimeter indicates pressure altitude when the barometric scale is set at
29.92” Hg
Which instrument condition is acceptable and would not require correction?
1) Red line missing
2) Case leaking
3) Glass cracked
4) Mounting screws loose
5) Case paint chipped
6) Leaking at line B nut
7) Will not zero out
8) Fogged
5
Aircraft instrument panels are generally shock-mounted to absorb
low frequency, high-amplitude shocks
What will be the result if the instrument static pressure line becomes disconnected inside a pressurized cabin during cruising flight?
The altimeter and airspeed indicator will both read low
The function of a display controller in an EFIS is to
Allow the pilot to select the appropriate system configuration for the current flight situation.
Which of the following causes of aircraft magnetic compass in accuracies may be compensated for by mechanics?
Deviation
How many of the following are controlled by gyroscopes?
1) Attitude indicator
2) Heading indicator
3) Turn needle of the turn-and-slip indicator
Three
Which of the following operating mechanisms would be found in a hydraulic pressure gauge?
Bourdon tube
Fuel flow transmitters are designed to transmit data
Electrically
Where may a person look for the information necessary to determine the required markings on an engine instrument?
1) Engine manufacturer’s specifications.
2) Aircraft flight manual
3) Instrument manufacturer’s specification
4) Aircraft maintenance manual
2 or 4
Cases for electrically operated instruments are made of
Iron or steel cases
An aircraft instrument panel is electrically bonded to the aircraft structure to
Provide current return paths
Data transmitted between components in an EFIS are converted into
Digital signs
The maximum deviation (during level flight) permitted in a compensated magnetic direction indicator installed on an aircraft certificated under Federal Aviation Regulation part 23 is
10 degrees
The maximum altitude loss permitted during an unpressurized aircraft instrument static pressure system integrity check is
100 feet in 1 minute
When an unpressurized aircraft’s static pressure system is leak checked to comply with the requirements of section 91.411, what aircraft instrument may be used in lieu of a pitot-static system tester?
1) Vertical speed indicator
2) Cabin altimeter
3) Altimeter
4) Cabin rate-of-change indicator.
5) Airspeed indicator
3
The green arc on an aircraft temperature gauge indicates
The desirable temperature range
A radar altimeter indicates
Altitude above ground level
Which instruments are connected to an aircraft’s static pressure system only?
1) Vertical speed indicator
2) Cabin altimeter
3) Altimeter
4) Cabin rate-of-change indicator
5) Airspeed indicator
1 and 3
1) Aircraft instruments are color-coded to direct attention to operational ranges and limitations.
2) Aircraft instruments range markings are not specified by title 14 of the code of Federal Regulations but are standardized by aircraft manufacturers.
Regarding the above statements,
Only no.1 is true
Which instruments are connected to an aircraft’s pitot-static system?
1) Vertical speed indicator
2) Cabin altimeter
3) Altimeter
4) Cabin rate-of-change indicator
5) Airspeed indicator
1,3, and 5
Which of the following instruments will normally have range markings?
Cylinder head temperature gauge, airspeed indicator
At sea level, when the average atmospheric pressure is 14.7 PSI, the barometric pressure is
29.92” Hg
Aircraft temperature thermocouple leads may
Not be altered and are designed for a specific installation
A certificated mechanic with at least an airframe rating may perform
Inspections and function checks on aircraft instruments
Turbine engine exhaust gas temperatures are measured by using
Chromel/alumel thermocouples
The operation of an angle-of-attack indicating system is based on detection of differential pressure at a point where the airstream flows in a direction
Not parallel to the true angle of attack on the aircraft.
How is flangeless instrument case mounted in an instrument panel?
By an expanding-type clamp secured to the back of the panel and tightened by a screw from the front of the instrument panel.
A certificated mechanic may perform
100-hour inspections of instruments
The method of mounting aircraft instruments in their respective panels depends on the
Design of the instrument case.
Resistance-type temperature indicators using wheatstone bridge or ratiometer circuits may be used to indicate the temperatures of which of the following?
1) Freeair
2) Exhaust gas temperature
3) Carburetor air
4) Coolant (engine)
5) Oil temperature
6) Cylinder head temperature
1,3,4, and 5
What marking color is used to indicate if a cover glass has slipped?
White
Which statement regarding an aircraft instrument vacuum system is true?
Dry-type vacuum pumps with carbon vans are very susceptible to damage from solid airborne particles and must take in any filtered air.
When performing the static system leakage check required by section 91.411, the technician utilizes
Negative pressure
A certificated mechanic with Airframe and Powerplant ratings may
Not perform repairs to aircraft instruments
Which of the following instrument discrepancies could be corrected by an aviation mechanic?
1) Red line missing
2) Case leaking
3) Glass cracked
4) Mounting screws loose
5) Case paint chipped
6) Leaking at line B nut
7) Will not adjust
8) Fogged
1,4,5,6
When installing an instrument in an aircraft, who is responsible for making sure it is properly marked?
The mechanic installing the instrument
Which of the following will cause inaccuracies in a magnetic compass that may be compensated for by an aircraft mechanic?
Deviation
What does a reciprocating engine manifold pressure gauge indicate when the engine is not operating?
The existing atmospheric pressure
How would an airspeed indicator be marked to show the best rate-of-climb speed (one engine operative)?
A blue radial line
A radar altimeter determines altitude by
Transmitting a signal and receiving back a reflected signal.
What is the fixed line mark attached to the compass bowl of a magnetic compass called?
Lubber line
A bourdon tube instrument may be used to indicate
1) Pressure
2) temperature
3) Position
1 and 2
When flags such as NAV, HDG, or GS are displayed on an HSI, the indication is
That function is inoperative
Which of the following instrument discrepancies would require replacement of the instrument?
1) Red line missing
2) Case leaking
3) Glass cracked
4) Mounting screws loose
5) Case paint chipped
6) Leaking at line B nut
7) Will not adjust
8) Fogged
2,3,7,8
Who is authorized to repair an aircraft instrument?
1) A certificated mechanic with an airframe rating.
2) A certificated repair station with an airframe rating.
3) A certificated repair station approved for that class instrument.
4) A certificated airframe repair station.
3
Which procedure should you use if you find a vacuum-operated instrument glass loose?
Install another instrument
What must be done to an instrument panel that is supported by shock mounts?
Bonding straps must be installed across the instrument mounts as a current path.
Instrument static system leakage can be detected by observing the rate of change in indication of the
Altimeter after suction has been applied to the static system to cause a prescribed equivalent altitude to be indicated.
If a static pressure system check reveals excessive leakage, the leak(s) may be located by
Isolating portions of the line and testing each portion systematically starting at the instrument connections.
A turn coordinator instrument indicates
Both roll and yaw
The function of a CRT in an EFIS is to
Display alphanumeric data and representations of aircraft instruments
Which condition would be most likely to cause excessive vacuum in a vacuum system
Vacuum relief valve improperly adjusted
The function of a symbol generator (SG) in an EFIS is to
Receive and process input signals from aircraft and engine sensors and send the data to the appropriate display.
An aircraft magnetic compass is swung to update the compass correction card when
Equipment is added that could affect compass deviation.
