081.01 SUBSONIC AERODYNAMICS .01 (basics) Flashcards
.01 Basics, laws and definitions
Taper ratio is the ratio of (tip/root) chord to (tip/root).
Taper ratio is the ratio of (tip) chord to (root).
- Taper Ratio: Tip/Root -
Angle of incidence is the angle between (…) and (…).
- Angle of incidence* is the angle between (aeroplane longitudinal axis) and (wing root chord line).
source: https://en.wikipedia.org/wiki/Angle_of_incidence_(aerodynamics)#/media/File:Aircraft_Angle_of_Incidence_(improved)–1080x660–25Mar2009.jpg
Angle of attack of a wing is the angle between (…) and (…).
Angle of attack is the angle between (chord line) and (relative airflow).
source: https://aviation.stackexchange.com/questions/21799/why-does-the-vortex-created-by-wing-affects-its-own-angle-of-attack
Wing loading is (…) devided by(…). The unit is (…).
Wing loading is (aircraft weight) devided by (wing area). The unit is (N/m2).
Aspect ratio = (…) ÷ (…)
or
Aspect ratio = (…) ÷ (…)
Aspect ratio = (wingspan2) ÷ (wing area)
or
Aspect ratio = (wingspan) ÷ (mean geometric chord)
List the SI unit for the following:
- mass
- acceleration
- weight
- velocity
List the SI unit for the following:
- mass = kg (kilogram)
- acceleration = m/s2 (meter per second squared)
- weight = N (newton)
- velocity = m/s (meter per second)
List the SI unit for the following:
- energy
- density
- temperature
- pressure
List the SI unit for the following:
- energy = J (joule)
- density = kg/m3 (kilogram per cubic meter)
- temperature = K (kelvin)
- pressure = Pa (pascal) → non-SI units: PSI (pounds per square inch)
List the SI unit for the following:
- force
- wing loading
- power
List the SI unit for the following:
- force = N (newton)
- wing loading = N/m2 (newton per meter squared)
- power = W (watt) → non-SI units: J/s (joules per second) = Nm/s (Newton meter per second)
kg•m/s2 is expressed in the SI-unit system as (…).
kg•m/s2 is expressed in the SI-unit system as (Newton).
Dihedral of a wing is the angle between the (leading edge/trailing edge/quarter chord line) of the wing and the (horizon/vertical axis/lateral axis).
- Dihedral* of a wing is the angle between the (0.25 chord line) of the wing and the (lateral axis).
- “The angle between the wing plane and the horizontal with the aeroplane in an unbanked, level condition.”*
source: https://nl.pinterest.com/pin/703617141762264820/
Wing sweep angle is the angle between the (leading edge/trailing edge/quarter chord line) of the wing and the (horizon/normal axis/lateral axis).
- Wing sweep angle* is the angle between the (quarter chord line) of the wing and the (lateral axis).
source: https://aviation.stackexchange.com/questions/4992/why-are-swept-wings-better-for-breaking-the-sound-barrier
An aeroplane’s angle of attack can be defined as the angle between its (longitudinal axis/lateral axis/speed vector) and (horizontal plane/longitudinal axis).
An aeroplane’s angle of attack can be defined as the angle between its (speed vector) and (longitudinal axis).
State he formula for dynamic pressure (q).
½ • ρ • v2
State Bernoulli’s equation for incompressible flow.
Ps + ½ • ρ • v2 = constant
Mean geometric chord of a wing is the (aspect ratio/wing area/wingspan2) divided by (wingspan/wing area/ taper ratio).
Mean geometric chord of a wing is the (wing area) divided by (wingspan).
relative thickness of an aerofoil is expressed in (meters / % chord / camber).
relative thickness of an aerofoil is expressed in (% chord).
Define indicated airspeed (IAS) and how it is derived.
Airspeed read directly from the airspeed indicator. It uses the difference between total pressure and static pressure.
TAS is IAS corrected for (instrument/position/compressibility/density) error(s).
TAS is IAS corrected for (instrument, position, compressibility and density) errors.
EAS is IAS corrected for (instrument/position/compressibility/density) error(s).
EAS is IAS corrected for (instrument, position and compressibility) errors.
CAS is IAS corrected for (instrument/position/compressibility/density) error(s).
CAS is IAS corrected for (instrument and position) errors.
State Newton’s first law.
A body will remain a rest or in uniform motion unless acted on by an external force
State Newton’s second law.
The force on an object is equal to its mass times its acceleration (F = m • a)
State Newton’s third law.
Every action has an equal and opposite reaction.
Compared to a two-dimensional airflow, in a three-dimensional airflow a (…) component exsist in addition to the chordwise speed component.
Compared to a two-dimensional airflow, in a three-dimensional airflow a (spanwise) component exsist in addition to the chordwise speed component.
- from wing root to wing tip -
