Aircraft Instrument Systems Flashcards
What three flight instruments are normally operated from the pitot-static system?
The airspeed indicator, which is connected to both pitot static pressure, plus the altimeter and the vertical speed indicator, which are connected to the static pressure source only.
What instrument indications will result if the static pressure line becomes disconnected inside the cabin of a pressurized aircraft?
The altimeter and airspeed indications will both be lower than normal, and the vertical speed indicator will indicate a momentary descent and then return to zero
What is required after replacement of components connected to the pitot-static system?
A leak test is required.
What are the sources of power for gyroscopic instrument operation?
Gyroscopic instruments can be operated either by vacuum, electricity, or by air pressure.
What causes an electric driven gyro rotor to tilt when the aircraft is turned?
Gyroscopic precession.
What is used as a guide for range marking of aircraft instruments?
The Aircraft Specifications or Type Certificate Data Sheets and the specific aircraft Maintenance or Flight manual.
Where are instrument range marking placed?
They are applied to the outer edge of the cover glass or over the calibrations on the dial face of the instrument.
What other type mark is required when range markings are applied to the glass instrument cover?
An index mark, which is a white line extending from the glass cover onto the instrument case to indicate slippage of the glass. Glass slippage would cause the range markings to be in error.
What is a synchro-type remote indicating system?
A synchro system is an electrical system used for transmitting information form one point to another. The three most common synchro systems are the Autosyn, the Selsyn, and the Magnesyn. These systems can be used to show movement and position of landing gear, wing flaps, oil cooler doors, or other movable parts of the aircraft.
What type fuel quantity system is an electronic fuel-measuring device that accurately determines the weight of the fuel in the tanks of an aircraft?
The capacitor-type fuel quantity system.
What is meant by “swinging a compass”?
It is the adjustment of the NORTH-SOUTH and EAST-WEST magnets in order to reduce deviation, which is the magnetic influences of the aircraft structure and electrical systems.
When inspecting a magnetic compass, the bowl should be filled with liquid and should not contain any bubbles or discolorations. What is the purpose of the liquid in the bowl?
It is to dampen the oscillations of the float.
Which instrument is used to indicate the speed of the crankshaft of a reciprocating engine and the speed of the main rotor assembly in a turbine engine?
A tachometer.
What type indicating system is used to indicate turbine engine exhaust gas temperature (EGT)?
A thermocouple system.
What does the manifold pressure gage indicate when the engine is not operating?
It indicates atmospheric pressure.
