Airplane Design Flashcards
An airplanes’ location of it’s CG (center of gravity-in front of wings) and CL (center of lift- at wings), determines its’ ________________ stability.
Longitudinal
As an airplanes’ CG moves aft, the plane becomes….
Less stable
To minimize side loads played on an airplane’s tricycle landing gear during touchdown, the pilot should
Keep the longitudinal body of the plane parallel with its direction of movement
Primary flight controls become (more/less) stable as airspeed (increases/decreases).
More as increases
-this is because there is more air moving over the control surfaces
Flaps allow pilots to…
Make steeper approaches without increasing airspeed
An airplane has been loaded in such a manner that the CG is located aft of the CG limit. One undesirable flight characteristic a pilot might experience would be…
Difficulty recovering from a stall
Longitudinal stability refers to an aircraft’s stability about which axis?
Lateral
An airplane that is more stable will….
Require less effort to control
Center of pressure is the same as….
Center of lift (at wings)
Changes in the center of pressure of a wing affect the aircraft’s…
aerodynamic balance and controllability
Purpose of rudder is to….
Control yaw
Loading an airplane the most aft CG will cause….
The plane to be unstable at all airspeeds
3 Types of Single Engine Aircraft that require a special endorsement to fly
High performance
-201+ hp
Complex
-retractable landing gear, controllable propeller, flaps
Tailwheel
-Conventional landing gear with wheel on tail
When does lift equal weight and thrust equal drag?
In unaccelerated flight
Bernouilli’s Principle states that when the speed of a fluid _________ it’s pressure _________. This also refers to an airplanes’ ___________.
Increases
Decreases
Wing
This causes air molecules to create a low pressure above the wing because they are hitting the leading edge of the wing, thus speeding up. Below the wing is still moving the same speed so it is a higher pressure. Air molecules want to move from high to low so lift is produced.
Angle of attack is defined as:
Angle between the chord line of the airfoil (wing) and the relative wind.
Ailerons control movement about which axis?
Longitudinal
(Roll)
Rudder control movement about which axis?
Vertical
(Yaw)
Elevator controls movement about which axis?
Lateral
(Angle of Attack)
Newton’s third law states in relationship to an airplane….
For every motion there is an opposite and equal reaction.
An additional upward force is created on the bottom of a wing as air hits and is deflected downward.
When do we have left turning tendencies in the airplane?
When climbing out. Need right rudder to correct.
When do we have right turning tendencies?
In a climb, need right rudder.
4 Left Turning Tendency Factors
Gyroscopic Procession- prop spins right causing a shift to the left
P-Factor- prop spins right, blade is scooping harder on the down spin than on up spin causing more thrust on the right, pushing plane left due to asymmetrical thrust
Torque- prop spins right, causes tail and fuselage to torque left
Spiraling Slipstream- air spins behind prop around the fuselage, striking left side of the tail causing it to turn the plane left
Why do we have canted wings (sloped upward towards the tips)?
Dihedral lines
-When we dip for a turn, more lift is produced on uplifted wing
-dihedral line becomes more horizontal as we turn, resulting in more lift on that wing
