Aviation Aircraft Systems 1 — Questions and Answers
Question 1: What is the purpose of the aircraft pitot-static system?
- To supply air for cabin pressurization
- To provide ram air pressure and static pressure for flight instruments (Correct answer)
- To cool the engine cylinders
- To supply fuel pressure to the carburetor
Correct answer: To provide ram air pressure and static pressure for flight instruments
The pitot-static system supplies ram air (pitot) pressure and atmospheric (static) pressure to the airspeed indicator, altimeter, and vertical speed indicator.
Question 2: What indicates a blocked pitot tube during flight?
- Altimeter freezes
- Airspeed indicator reads zero or fails to change with actual speed changes (Correct answer)
- Turn coordinator fails
- Vertical speed indicator shows a steady climb
Correct answer: Airspeed indicator reads zero or fails to change with actual speed changes
A blocked pitot tube prevents ram air from entering the system, causing the airspeed indicator to read zero or remain frozen at the speed when the blockage occurred.
Question 3: What is carburetor icing, and at what conditions is it most likely?
- Ice in the fuel tank; occurs below -40°C
- Ice forming in the venturi of the carburetor due to cooling of fuel-air mixture; most likely in high humidity, 20°F–70°F (-7°C to 21°C) (Correct answer)
- Ice on the engine cowling; occurs in heavy precipitation
- Ice blocking the exhaust; occurs in winter only
Correct answer: Ice forming in the venturi of the carburetor due to cooling of fuel-air mixture; most likely in high humidity, 20°F–70°F (-7°C to 21°C)
Carburetor icing forms in the venturi as fuel vaporization and pressure drop cause temperature to fall below freezing, even in mild ambient temperatures with high humidity.
Question 4: What is the function of the aircraft vacuum system?
- To provide pressure for cabin pressurization
- To drive the gyroscopic instruments (attitude indicator and heading indicator) (Correct answer)
- To supply fuel pressure as a backup
- To cool the avionics bay
Correct answer: To drive the gyroscopic instruments (attitude indicator and heading indicator)
The vacuum system powers gyroscopic flight instruments — typically the attitude indicator and directional gyro (heading indicator).
Question 5: In a normally aspirated aircraft engine, as altitude increases, what happens to engine power?
- Power increases due to cooler temperatures
- Power decreases because air density decreases (Correct answer)
- Power remains constant up to the service ceiling
- Power increases to the critical altitude then drops
Correct answer: Power decreases because air density decreases
As altitude increases, air density decreases, reducing the mass of air entering the engine and therefore decreasing engine power output.
Question 6: What does the VSI (Vertical Speed Indicator) display?
- Groundspeed in knots
- Rate of climb or descent in feet per minute (Correct answer)
- True airspeed
- Density altitude
Correct answer: Rate of climb or descent in feet per minute
The VSI uses the rate of change of static pressure to indicate the aircraft's rate of climb or descent in feet per minute.
Aviation Aircraft Systems 1
What is the purpose of the aircraft pitot-static system?