05 Air Speed Indicator Flashcards
Describe how an Air Speed Indicator operates;
- What feeds it
- Components
- How it operates
- Feed by a Static Pressure feed and a Pitot Pressure feed
- Static feeds into the case
- Pitot feeds directly into a pressure capsule
- As dynamic pressure increases the pressure capsule expands indicating an increase in speed
What Errors are associated with an Air Speed Indicator?
- Instrument
- Manoeuvre
- Position
- Compressibility: Only applicable at TAS > 300kts
- Density: Due to altitude and temperature
Name the following speeds/ranges for a single engine Air Speed Indicator:
- Start of the white band
- Start of the green band
- White band
- End of the white band
- Green band
- Start of yellow band
- Yellow band
- Red line
- Vso: Stall speed in landing configuration
- Vs1: Stall speed in the normal configuration
- Speed range flaps extended
- Vfe: Max speed flaps extended
- Normal operating speed range
- Vno: Max speed normal operating
- Cautionary speed range
- Vne: Velocity never exceed
Name the following speeds/ranges for a multi engine Air Speed Indicator:
- Additional Red line
- Additional blue line
- Vmca: Min control speed in the air (one engine)
- Vyse: Best rate of climb speed (one engine)
What happens if the Pitot feed becomes blocked in an Air Speed Indicator during the climb?
Air Speed Indicator will Over Read
What happens if the Static feed becomes blocked in an Air Speed Indicator during the climb?
Air Speed Indicator will Under Read
What is the nemonic used when working out how an Air Speed Indicator will react if one of the feeds is blocked?
PUDSOD
What happens if the Pitot feed leaks in an Air Speed Indicator?
ASI will under read due to a drop in Pitot pressure
What happens if the Static feed leaks in an Air Speed Indicator in a Pressurised cabin?
Under read due to an increase in static pressure
What happens if the Static feed leaks in an Air Speed Indicator inside a Non-Pressurised cabin?
Slight over read due to a reduced cabin pressure (caused by cabin suction)
On an Air Speed Indicator, what does a ‘Barbers Pole’ (or second stripped needle indicate?
The Vmo
