Flight INstruments Flashcards
Pitot-static System
Instruments?
Air Sources?
Instruments
•Altimeter
•Vertical Speed Indicator
•Airspeed Indicator
Air Sources •Pitot Tube -Ram/Dynamic Pressure •Static Port =Static Air
Do Glass Aircraft do have pitot-static systems?
What lines are connected to the ADC and what does ADC mean?
What else is it connected along with?
Yes
•The pitot line and static line are connected to the Air Data Computer (ADC)
oAlong with the OAT
Altimeter
What is inside?
What are the markings?
What is the window called?
Aneroid wafer = sealed capsule of air. Shows indication or climb of altitude on face of the instrument.
Markings •Hundreds •Thousands •Ten Thousands •Kollsman Window
Types of Altitude
Indicated Altitude – read right off the instrument
Absolute Altitude – height above ground (AGL)
True Altitude – height above sea level (MSL)
Pressure Altitude – height above standard datum plane of 29.92” Hg
Density Altitude – pressure altitude corrected for non-standard temperature (15°C)
91.121 Altimeter Settings
Below 18,000 MSL
- Current reported altimeter setting within 100 nm of the aircraft
- If no setting is available upon departure, the elevation of the departure airport may be set in to the altimeter
At and above 18,000 MSL
•All aircraft set altimeters to 29.92
Altimeter Malfunctions (1)
Blocked Static Port
•Solution – Alternate Static Source
Vertical Speed Indicator - Components
- Diaphragm
- Calibrated Leak
- Direct Static Pressure
Vertical Speed Indicator
As the altitude changes, pressure changes
Air in the diaphragm and case want to equalize with outside pressure
Diaphragm equalizes same rate as outside pressure
Case is restricted to equalizing by the
Calibrated Leak
This restriction allows the rate of climb or descent to be measured and is indicated on the face of the instrument
Vertical Speed Indicator Errors (1)
Static Blockage •Solution – Alternate Static Source Indication Lag •Allow 6-9 seconds to stabalize •Due to Calibrate Leak
Airspeed Indicator - System and Operation
- Only pitot-static instrument that uses both the static port and pitot tube
- Speed increases, ram air moves into pitot tube and expands diaphragm
- Static Port maintains ambient pressure in case
Airspeed Indicator Markings
White Arc?
Green Arc?
Yellow Arc?
Red Line?
White Arc – Flap Operating Range
•Vso to Vfe
Green Arc – Normal Operating Range
•Vs to Vno
Yellow Arc – Caution Range
•Vno to Vne
Red Line
•Vne
Types of Airspeeds
Indicated Airspeed (IAS) – read directly off instrument
Calibrated Airspeed (CAS) – IAS corrected for installation and position errors
True Airspeed (TAS) – CAS corrected for non-standard pressure and temperature and pressure
Ground Speed
Airspeed Indicator Malfunctions
3
Blocked Pitot Tube
Blocked Static Port
Blocked Drain Hole (drain hole allows excess water out)
•Solutions
oPitot Heat
oAlternate Static Source
Gyroscopic Instruments
Instruments? (3)
Vacuum Systems? (2)
Instruments
•Attitude Indicator
•Heading Indicator
•Turn Coordinator
Vacuum Systems
•Engine Driven
•Electrically Driven
G1000
Do glass aircraft have gyroscopic instruments?
What sensors replace conventional systems?
What reference system is included?
Does the c172 have a backup ?
Glass Aircraft do have gyroscopic instruments
•Accelerometers and Rate Sensors replace conventional systems
oAttitude and Heading Reference System (AHRS)
C172 does have a backup vacuum standby attitude indicator