A104 Flashcards
As weight increases, aircraft performance _____________.
Decreases
Define useful load
The variable weight—pilot, passengers, baggage, usable fuel
Define center of gravity
The balance point on an aircraft
In weight and balance calculations, what is the arm?
The distance from the datum line to the item
Define datum line
An imaginary vertical plane which all measurements are taken from
What affects does an aft CG have in relation to stall speed, stability, and cruise speed?
Stall speed: lower (flies at a lower angle of attack because of the additional downward force on tail)
Stability: less stable (elevator has a shorter arm from CG, requiring greater deflection to produce same result)
Cruise speed: higher cruise speed (less downward force on tail which requires less lift which in turn creates less drag)
What effects does a forward CG have on stall speed, stability, and cruise speed?
Stall speed: higher indicated stall speed (total lift increased with higher angle of attack which increases drag)
Stability: more stable (elevator has longer arm which will require less deflection to produce same results)
Cruise speed: slower cruise speed (more lift required, higher angle of attack, more drag)
define moment
The product of the weight multiplied by the arm
Where is the air most dense?
Sea level (close to ground)
How does air density affect performance?
Greater density, better performance
What main three environmental conditions affect aircraft performance?
Air pressure, temperature, humidity
Increase in air pressure causes a(n) ___________ in air density.
Increase
Higher air temperature equals _____________ air density
Lower
What affect does high temperature have in aircraft performance?
Lower aircraft performance
Define humidity
Amount of water vapor in the air
Water vapor is ___________ than air.
Lighter
As humidity increases, air density ____________.
Decreases
As humidity increases, aircraft performance ____________.
Decreases
As humidity increases, air density ___________.
Decreases
What altitude and pressure, temp, humidity levels are best for aircraft performance?
Sea level, high pressure, low temps, low humidity
What is pressure altitude?
Pressure altitude tells you how high you have to fly to have the same pressure you have now
**Height above the standard datum plane
What altitude the plane feels like it’s flying at based off atmospheric conditions
What is the standard temperature lapse rate?
Increase in 1000ft = decrease by 2 degrees Celsius
What is the standard pressure lapse rate?
Increase in 1000ft = decrease in 1in mmHg
How do you determine the pressure altitude when preparing preflight?
Apply correction factor (added or subtracted) to the known field elevation.
