airplane nomenclature and other useful definitions

Question 1

Stabiliser

Answer 1

noun: a device to improve the tendency
of an aircraft to return to its original
attitude after being deflected

Question 2

Stabilator

Answer 2

noun: allmoving tailplane

Question 3

Aft

Answer 3

referring to the back part of a plane. Rear is also used with the same meaning. It contrasts with forward.

Question 4

Empennage

Answer 4

arrangement of stabilizing surfaces at the tail end of an aircraft; typically consists of the horizontal stabilizer, the elevators, the vertical stabilizer, and the rudder

Question 5

Squall

Answer 5

noun: a sudden
increase in wind speed lasting for several minutes

Question 6

Stall

Answer 6

noun 1. a loss of lift caused
by the breakdown of airflow over the wing when the angle of attack passes a
critical point In some configurations it
is possible for the buffet speed to be less
than the required 7% margin ahead of
the stall. 2. a situation in which an
engine or machine stops suddenly
because an opposing force overcomes
its driving power Compressor stall
can be caused by ice formation in the
air intake

Question 7

Buffet

Answer 7

noun: a shaking movement of the aircraft caused by the breakdown of the airflow over the upper surface of the wing

“The aircraft was buffeted by strong crosswinds as it made its final approach to land.”

COMMENT: Buffet is a warning to the pilot that the smooth airflow over the wing is breaking down and that he should take corrective action to prevent a stall.

Question 8

buffet speed

Answer 8

noun: the speed at which buffet is first noticed

Question 9

elevators

Answer 9

used to adjust, or control, the pitch of the airplane. connected to the control wheel or stick of the airplane and are moved by the forward and backward motion of the control

Question 10

rudder

Answer 10

noun: a control surface
on the fin which rotates the aircraft about its vertical axis to produce yaw

The rudder does not turn
the aircraft. It is used, together with aileron deflection, to initiate turns, to
balance forces in turns and to
counteract yawing motions created by the propeller during flight. The rudder
pedals are mounted on the floor of the cockpit

makes small directional changes in turns

Question 11

trim tabs

Answer 11

most airplanes have small hinged sections on trailing edge of the elevators; sometimes move in opposite direction of control surface.

the purpose is to reduce the necessary force on the control wheel, or yoke, for pilot to maintain desired flight attitude

Question 12

strut

Answer 12

/ noun a bar or rod used to
strengthen a structure against forces
from the side

Question 13

aileron

Answer 13

which are used for roll control. The ailerons are
coupled so that when one swings up the other swings down

Question 14

flap

Answer 14

noun: a movable control surface on the trailing edge of an aircraft wing, used primarily to increase lift and
drag during final approach and landing

Flaps should be retracted immediately after landing to decrease lift and
therefore increase brake effectiveness.

Question 15

leading edge

Answer 15

forwardmost edge of an aircraft wing

Question 16

trailing edge

Answer 16

backmost edge of aircraft wing

Question 17

chord

Answer 17

imaginary straight line connecting the leading edge with the trailing edge of airfoil.

used for determining the geometric angle of attack

Question 18

mean camber line

Answer 18

the line equal distance from the upper and lower surfaces of the wing.

the camber is the curvature of the mean camber line. a wing with an airfoil with a great deal of curvature in its mean camber is said to be highly cambered. a symmetric airfoil has no camber

Question 19

relative wind/relative airflow

Answer 19

the direction of wind at some distance from the wing. it is parallel to and opposite to the direction of motion of the wing.

velocity of the relative wind = speed of the wing

Question 20

Axes of Control

Answer 20

roll, pitch, and yaw

roll - longitudinal axis
pitch - lateral axis
yaw - vertical axis

Question 21

four forces

Answer 21

lift, weight, thrust, and drag

Question 22

in straight-and-level flight, what does net lift equal?

Answer 22

weight

Question 23

Mach number

Answer 23

the speed of the airplane, or speed of the air, measured in units of the speed of sound.

an airplane traveling at mach 2 is going twice the speed of sound

Question 24

what is the value of Mach 1 at sea level?

Answer 24

760 m/h

Question 25

what is the mach value at an altitude of 35,000 feet?

Answer 25

660 mi/h

speed of sound decreases with altitude to about 35,000 feet, and remains essentially constant to an altitude of 80,000 ft. no airplanes fly above this altitude with the exception of space shuttle on its way back from space

Question 26

kinetic

Answer 26

adjective: referring to motion or something produced by motion

Question 27

equation for kinetic energy

Answer 27

K.E. = 1/2mv^2

Question 28

what three measures of pressure are there?

Answer 28

total, static, and dynamic

Question 29

what is the equation for total pressure?

Answer 29

total = static + dynamic

Question 30

explain which directions total, static, and dynamic pressure is measured

Answer 30

total, or Pitot pressure, is measured perpendicular to the airflow

static is measured perpendicular to the airflow, but through a hole in the wall.

dynamic pressure, or pressure due to the motion of the air, is a pressure parallel to the flow of air. the dynamic pressure is proportional to the kinetic energy in the air. the faster the air goes, the higher the dynamic pressure

Question 31

differential pressure

Answer 31

the difference in pressure between total, or Pitot, and static pressure.

Question 32

static port

Answer 32

the hole that measures the static pressure of the air

Question 33

geometric angle of attack

Answer 33

the angle between the mean chord of the wing (a line drawn between the leading edge of the wing and the trailing edge) and the direction of the relative wind.

Question 34

critical angle of attack

Answer 34

At this angle the forces become so strong that the air begins to separate from the wing and the wing loses lift while experiencing an increase in drag, a retarding force.