Performance + Limitations Flashcards
(64 cards)
4 dynamics of force
lift, weight, thrust, drag
what flight condition will result in the sum of opposing forces being equal
in steady-state, straight-and-level, unaccelerated flight
what is an airfoil? Example?
device which gets a useful reaction from air moving over its surface, namely LIFT. Wings, horizontal stabilizer,
what is angle of incidence
angle formed by the longitudinal axis of airplane and the chord of the wing. measured by angle which wing is attached to the fuselage
what is relative wind
direction of airflow with respect to the wing
what is the angle of attach
angle between the wing chord line and direction of the relative wind
what is Bernoulli’s principle
the pressure of a liquid or gas decreases at points where the speed increases
example of Bernoullis principle
the wing has increased velocity above its surface, decreasing pressure above the airfoil
what are several factors that affect both lift and drag
wing area, shape of the airfoil, angle of attack, velocity of the air, air density
what is torque effect
involves newtons 3rd law, as the prop is turning in one direction, the airplane wants to go the opposite direction
what reaction does torque effect have on the airplane in the air
it wants to make the airplane roll
what reaction does torque effect have on the airplane on the ground
during the takeoff roll, since the left side of the airplane is being forced down by torque reaction, more weight is on the left causing more drag and friction making left turning tendency
what are the 4 left turning tendencies
torque effect, gyroscopic precession, p-factor, and slipstream
describe the torque effect left turning tendency
rotation of prop (from the cockpit) to the right, tends to roll/bank the airplane to the left
describe gyroscopic precession left turning tendency
if the axis of the prop is tilted, the resultant force will be excepted 90 degrees ahead in the direction of the rotation
describe the slipstream left turning tendency
the slipstream strikes the vertical tail surface on the left side pushing the tail to the right and yawing it to the left
describe p-factor left turning tendency
the downward moving blade moves faster than the other side meeting the relative wind causing greater thrust on the downward part on the right side and forces the plane to war to the left
what is centrifugal force
the “equal and opposite reaction” of the airplane to change in direction and it acts “equal and opposite” to the horizontal lift component
what is load factor
the ratio of the total load supported by the airplanes wing to the actual weight of the airplane + contents
why is load factor important to pilots (2 reasons)
- the dangerous overload that is possible to impose on the aircraft structure
- an increased load factor increases stalling speed and makes it possible at seemingly safe flight speeds
what situations can result in load factors reaching maximum extent
level turns - especially those after45/50 degrees of bank
turbulence - can change angle of attack suddenly, resulting in large loads
speed - the amount of excess load that can be imposed on wind depends on how fast the airplane is flying
what are the different operational categories of aircraft?
normal, utility, aerobatic
what operational category is the C-172S
normal/utility
what does an increase in load factor have on stalling speeds
as it increases, stalling speed increases
