OGINS 01.06 – Air Data Computer (ADC) – LMS

Results

Q1. A temperature sensor having a recovery factor of 0.75 indicates 30°C. Static Air Temperature (SAT) is 25°C. How high is the Ram-rise?

6.7°C

40°C.

5°C

18.8°C

5°C

Q2. The standard temperature for all our aerodynamic computations is:

273°K or 492°FR.

15°C or 59°F

0°C or 32°F.

0°F or 460°R.

15°C or 59°F

Q3. The ram air temperature (RAT) is defined as:

the OAT (outside air temp.) plus the SAT.

the temperature raise caused by adiabatic compression.

SAT plus the ram rise.

the temperature of the ram rise.

SAT plus the ram rise.

Q4. In An Air Data Computer (ADC), aeroplane altitude is calculated from:

The difference between absolute and dynamic pressure at the fuselage

Measurement of absolute barometric pressure from a static source on the fuselage

Measurement of outside air temperature (OAT)

Measurement of elapsed time for a radio signal transmitted to the ground surface and back

Measurement of absolute barometric pressure from a static source on the fuselage

Q5. To obtain total air temp. (TAT) the airflow to the sensor:

must not be submitted to adiabatic compression and friction.

must be brought to rest with the removal of the ram rise.

must be laminar without any turbulence or vortex.

must be brought to rest without addition or removal of heat.

Q6. The recovery factor of a “flush bulb” temperature sensor generally varies from:

0.90 to 1.00.

0.35 to 0.50

0.75 to 0.90.

0.50 to 0.75.

0.35 to 0.50

Q7. The advantages provided by an air data computer to indicate the altitude are: 1. Position/pressure error correction 2. Hysteresis error correction 3. Remote data transmission capability 4. Capability of operating as a conventional altimeter in the event of a failure. The combination of correct statements is:

2,3,4

1,2,3

1,2,3,4

1,3,4

Q8. An Air Data Computer (ADC):

Transforms air data measurements into electric impulses driving servo motors in instruments

Is an auxiliary system that provides altitude information in the event that the static source is blocked

Measures position error in the static system and transmits this information to ATC to provide correct altitude reporting

Converts air data measurements given by ATC from the ground in order to provide correct altitude and speed information

Transforms air data measurements into electric impulses driving servo motors in instruments

Q9. The measurement of SAT (static air temperature) by direct means is not possible on some (fast) aircraft because:

the boundary layer around the aircraft gets very turbulent.

of the effects from adiabatic compression and friction.

most temperature sensors have a low recovery factor.

the airflow causes too much cooling of the sensing probe.

of the effects from adiabatic compression and friction.

Q10. Given: Ts the static temperature (SAT), Tt the total temperature (TAT), Kr the recovery coefficient, M the Mach number. The total temperature can be expressed approximately by the formula:

Tt = Ts(1 - 0.2 M^2)

Tt = Ts(1 + 0.2 M^2)

Tt = Ts / (1 + 0.2 Kr.M^2)

Tt = Ts(1 + 0.2 Kr.M^2)