Machmeter/ADC Flashcards
(22 cards)
What is LSS
Local Speed of Sound = 38.94 x (square root of temp in kelvin)
Therefore changes with temp and pressure
What is Mach number
TAS / LSS
What is the free stream machine number
The MN of undisturbed airflow away from the aircraft
What is critical machnumber
The free stream mach number where local mach becomes sonic anywhere along the aircraft
What does a machmeter use
A ratio of dynamic to static pressure
Machmeter errors
BLIMP ONLY
what is mmo
Maximum mach operating number - never to exceed
Always shown with the white and red barbers pole
What is pressure altitude
The altitude read when set 1013hPa
What is true altitude
Altitude when QNH is set
What is the CTM
Chicken Tikka Masala
CAS , TAS , MACHNUMBER
from left to right on an altitude,speed graph
What happens to CTMin an isothermal layer
TAS and Mn merge and become the same
What happens to CTM in an inversion
TAS and MN switch places
What happens if you have a const FL and CAS entering Cold air
TAS - decreases
MN - const
LSS - decreases
TRUE ALT - lower
AIR DENSITY - increases
What happens if you have const CAS and FL entering warm air
TAS - Increases
MN - const
LSS - increases
TRUE ALT - higher
AIR DENSITY - decreases
What does the machmeter position error vary with
Angle of attack and TAS
What is the ADC
Air data computer
What are the main inputs for an adc
Pitot pressure
Static pressure
Total air temp
What is a periphery input to the adc
Angle of attack measurement
How does the adc convert data
It receives analogue measurements then converts them via a transducer into digital information
What is an advantage of a transducer
Can be installed close to the sensors
How do you have redundancy in the adc
Two displays and multiple sets of data
Total air temp can be both and input and an output
YES
