Stuff
Define and describe adverse yaw?
Adverse yaw is an airplane's natural tendency to swing its nose in the opposite direction of a roll. This happens because the downward-moving aileron creates extra drag on that wing, which pulls the aircraft's nose away from the intended turn.
Define critical angle of attack
The critical angle of attack is the maximum angle between a wing's chord line and the relative wind where smooth airflow can create lift before an aircraft stalls.
What are the 4 left turning tendencies of an aircraft?
The four left-turning tendencies of a propeller-driven airplane are torque effect, spiraling slipstream, P-factor (asymmetric propeller loading), and gyroscopic precession.
what A/C design features manage Directional Stability about what axis?
Directional stability is managed about the vertical axis (also called the normal or yaw axis). Aircraft design features like the vertical stabilizer (fin) and wing sweep manage directional stability about the vertical (yaw) axis by generating aerodynamic restoring forces whenever the aircraft slips sideways.
Where does wing stall originates and progresses from on a rectangular planform wing on a training aircraft?
On a rectangular planform wing (on training aircraft like the Cessna 172 or Piper Cherokee), a wing stall originates at the wing root (the section closest to the fuselage) and progresses outward toward the wingtips.
Define and describe aircraft load factor:
Aircraft load factor is the ratio of the total lift produced by an airplane's wings to its total weight, expressed in units of acceleration or G-forces.
At approximately what angle (range) of attack will an training aircraft wing stall?
When the aircraft exceeds its critical angle of attack, it will stall—for many GA aircraft, that occurs between 16 and 18 degrees
Describe gyroscopic precession:
When an object spins, it builds up angular momentum. This momentum makes the object resist changes to its axis (a property called rigidity in space) because every piece of the rotating mass changes position continuously, the reaction gets delayed and shows up 90 degrees (a quarter turn) later around the circle.
Define Dutch Roll
A Dutch roll involves a combined oscillation around the yaw axis (vertical axis, or tail-wagging side-to-side) and the roll axis (longitudinal axis, or rocking the wings up and down).
What does the yellow area in a Vg diagram correspond to on an aircraft airspeed indicator?
The yellow area on a Vg diagram corresponds to the caution range (the yellow arc) on an aircraft airspeed indicator?
What is the load factor increase for 60 deg AoB?
A 60-degree angle of bank (AoB) in a constant-altitude, coordinated turn increases the load factor to 2.0 Gs, which is a 1.0 G increase (or a doubling of the normal 1.0 G straight-and-level load factor)
What instruments does an aircraft have to tell AoA without AoA indexers installed?
Without a dedicated Angle of Attack (AoA) indexer or dedicated AoA gauge, an aircraft does not have a single instrument that directly displays AoA. Instead, pilots estimate and monitor AoA using a combination of standard primary flight instruments and physical feedback cues
What is P-factor (asymmetric propeller loading)
P-factor (asymmetric propeller loading) happens when an aircraft flies at a high angle of attack, causing the descending propeller blade to bite more air and produce more thrust than the ascending blade. This uneven thrust creates an aerodynamic imbalance that yaws the airplane off course, typically to the left in standard clockwise engines
What are the aircraft performance effects of forward aircraft loading (with-in C.G. limits)?
A forward center of gravity (CG) within safe limits increases stall speed, decreases cruise speed, and increases fuel burn because the wings must generate extra lift to counter heavy tail-down force.
Define maneuvering speed
Maneuvering speed (Va)is the maximum speed at which you can fully and abruptly deflect an airplane's flight controls without causing structural damage.
At or below maneuvering speed, the aircraft will stall before the aerodynamic forces can exceed the structural load limit of the airframe.
What is the stall speed increase (%) for 60 deg AoB?
The stall speed increases by approximately 40% (41.4 to be exact) at a 60-degree angle of bank.
What does an illuminated upper chevron on a AoA gauge indicate and what pilot action should be taken?
An illuminated upper chevron on an Angle of Attack (AoA) gauge or indexer indicates that the aircraft is flying at an excessively high Angle of Attack, meaning the airspeed is too slow and the aircraft is approaching an aerodynamic stall - lower the AoA.
Below what speed is air in knots considered incompressible?
Air flow is generally considered incompressible below approximately 260 knots (or below Mach 0.3).
what are the aircraft performance effects of aft aircraft loading (with-in C.G. limits)?
An aft center of gravity (C.G.) within legal limits improves aircraft performance by increasing cruise speed and reducing fuel consumption, but it decreases longitudinal stability and lowers stall speeds.
Speed of sound at sea level?
The speed of sound at sea level in air is approximately 343 meters per second (761 mph/661 kts) at 15 °C (59 °F).
For an aircraft that normally stalls at 40kts, what is the stall speed in a 60 deg AoB turn?
40 x .4 =16 40+16=56
super precise: At a 60-degree angle of bank, the aircraft's accelerated stall speed will increase to 56.6 knots (commonly rounded to 57 knots)
Increaseng A/S with a constant AoB will do what to turn radius?
Increasing airspeed (A/S) with a constant Angle of Bank (AoB) will increase the turn radius.
Why are sweep back wings used for high speed a/c?
Swept-back wings are used on high-speed aircraft primarily to reduce wave drag and delay the onset of shock waves as the plane approaches the speed of sound. Sweeping the wing backward causes the air to flow over it at an angle, which artificially reduces the effective airspeed experienced by the wing's profile. This allows the aircraft to cruise at transonic or supersonic speeds much more efficiently while maintaining structural stability.
The green arc on a aircraft airspeed indicator shows stall speed with what CG loading (forward or aft)?
Aircraft certification regulations mandate that airspeed indicators reflect the most conservative (worst-case) scenario for safety. Because a forward CG requires greater tail-down force—increasing the wing's effective load and raising the stall speed—the instrument must display this higher, safer threshold. Conversely, an aft CG naturally lowers the stall speed, which is a "best-case" scenario not depicted by the green arc.
Speed of sound at 30,000 in knots?
589.3 (roughly 590) knots at 30,000 feet.
Decrease with temperature decrease.