11:5:1 Instrument Systems Flashcards
What name is given to the arrangement of the most important flight instruments
BASIC T
Other than the instruments in the basic T what additional flight instruments are there
- Vertical speed indicator
- Mach meter
- Temperature indicators
What component is ALWAYS in the same place in the basic T
The Altimeter
How many pointers do small aircrafts altimeters have
2
1 for 100ft and 1 for 1000ft. Larger aircraft which fly higher have an additional one for 10,000ft
How do altimeters work
They measure the static pressure of the atmosphere and indicate it in feet
In the standard atmosphere what is the static pressure at sea level
1013.25 hectopascals Hpa
With increasing altitude the pressure decreases. At 18k feet what is the static pressure
50% at sea level and at 36k ft its 25%
What is the sensitive gauge called in a pneumatic altimeter called
An aneroid bellows
Large aircraft aren’t driven by a bellows so how are they driven
By an (ADC) Air Data Computer
Does the accuracy of an altimeter increase or decrease with altitude
They accuracy of altimeters decreases with altitude
What are conditions are altimeters calibrated to
Conditions of the standard atmosphere
What is QNH
The baro is set to the actual pressure of the airport
What barro code is set for sea level at 15° and 1013hpa
QNH
What airport code is set for the airport that the aircraft is and not sea level
QFE
How do pneumatic airspeed indicators work
The total pressure line is connected to the inside of the bellows and the static pressure is distributed to the indicator case so that it surrounds the bellows
What happens to the bellows in an airspeed indicator at low medium and high speeds
Low - The total pressure is low and the bellows are compressed
Medium - All mechanical parts are in the present condition
High - Total pressure is high and the bellows expand
In small aircraft the speed limits are marked with coloured ranges and lines on the airspeed indicator scale what are they
Green band - Normal operating range
The white band - Full flap operating range
Yellow band - Caution range. This speed must only be used in smooth air with no hard manoeuvres
What are VSO, VS1, VFE, VNO, VFE
VSO - Stall speed in landing config. Flaps and gear are down
VS1 - Stall speed in clean config with max weight
VFE - Max speed with flaps extended
VNO- Max speed for cruise flight
VNE - Never exceed, max allowed airspeed
What do jet aircraft have on the airspeed indicator to indicate maximum speed
A pointer, the reason for this is it is not a fixed speed like in a small piston aircraft
What is (VMO) Maximum Operating Velocity
The limit of dynamic pressure acting on the skin of the aircraft
What is the purpose of the (VSI) Vertical Speed Indicator
To show the pilot the rate of climb or decent in ft per min
What is the purpose of the Mach meter
Indicated the ratio of the aircrafts true airspeed to the actual speed of sound
What component can a Mach meter be integrated in to
Airspeed indicator
What is the static air temperature SAT
The temperature of the undisturbed air around the aircraft. It’s also called Outside Air Temperature OAT
What are the 2 types of temperatures indicated for aircraft
- Static Air Temperature (SAT)/ Outside Air Temperature
- Total Air Temperature (TAT)
What is the TAT probe called after the manufacturer
Rosemount probe
What do the Altimeter, The Airspeed Indicator and the Vertical speed indicator need to indicate correct values
Static pressure
