aircraft instruments and systems. Flashcards
what are the pressure flight instruments
- Airspees Indicator (ASI)
- Altimeter
- Vertical Speed Indicator (VSI)
how do pressure flight instruments work
Pressure instruments measure atmospheric pressure by pitot-static system which is a combined system measuring the total pressure and the static pressure.
The total pressure, also called the pitot pressure, is measured, by the pitot probe.
The static pressure, which is measured either by the static port on the pitot probe or by a separate static vent.
The difference between the two will give a measurement of the dynamic pressure.
the dynamic and/or the static pressure measurements are thr basis of the flight instrument reading.
airspeed indicator (ASI) instruments errors
- Instrument error
- Pressure error
- Density error
- Compressibility error
- Maneouver error
- Blocked pitot static system
What are the altimeter indications and actions for a blocked static port?
the altimeter will display the altitude where the blockage occurred
errors that the vertical speed indicator (VSI) instrument suffer from
- Instrument time-lag error
- Pressure error (also known as position error)
- Maneouver error
What are the gyro flight instruments
- Directional indicator (DI)
- Artificial horizon (AH)
- Turn and slip indicator or turn coordinator
gyroscopic wander
Any movement of the gyroscope’s spin axis away from its fixed direction is called wander, and if this occurs, it gives rise to inaccurate instrument readings.
the advantage of the directional indicator (DI) over the magnetic compass
The rigidity of the DI gyroscope gives steadier heading information than the magnetic compass, which suffers from turning and acceleration errors.
Describe the earth’s magnetic field.
The earth has a magnetic iron core, which makes the earth act like a giant magnet with north and south magnetic poles. The magnetic poles are slightly offset from the geographic poles, and the earth’s surface is covered with a resulting weak magnetic field that radiates from its magnetic poles.
the purpose of a flight management system (FMS)
The purpose of an FMS is to manage the aircraft’s performance and route navigation to achieve the
optimal result.
the purpose of an autopilot system
The purpose of an autopilot system is to relieve the pilot of the physical and mental fatigue of flying the aircraft, especially during long flights. This will result in the pilot being more alert during the critical phase of landing the aircraft, thus improving safety
the advantages of a hydraulic system over a pneumatic system
Hydraulic fluid is incompressible, and this makes the system respond instantly and more efficient.
the advantages of a pneumatic system over a hydraulic system
- Air weighs less than hydraulic fluid, which is beneficial to the aircraft’s overall weight limitations.
- You do not have any problems of availability and cost with air, which you could have with hydraulic fluids.
Describe a typical braking system
Most aircraft braking systems use hydraulic fluid pressure to move friction brake pads (that are connected to small hydraulic pistons) against rotating brake plates to slow down the plates and therefore the wheel.
