Helicopter Written Flashcards
An _____ is a structure or body which produces a useful reaction to air movement. Airplane wings, helicopter rotor blades, and propellers are airfoils.
airfoil
The _____ ______ is an imaginary straight line from the leading edge to the trailing edge of an airfoil.
chord line
In aerodynamics, relative wind is the wind felt by an ____________. It is created by the movement of air past an airfoil, by the motion of an airfoil through the air, or by a combination of the two.
airfoil
Relative wind is _______ and in the ______ direction to the flight path of the airfoil.
paralell
opposite
The _______ __ __________ is the angle at which a wing is attached to the aircraft fuselage.
angle of incidence
The _________ ___ __________is the angle between the chord line of the airfoil and the relative wind.
angle of attack
An airplane has three axes of rotation: the _____ axis, _________ axis, and the _______ axis.
lateral
longitudinal
vertical
The _______ ___ ________ (the imaginary point where all the weight is concentrated) is the point at which an airplane would balance if it were suspended at that point.
center of gravity
The four aerodynamic forces which act upon an aircraft are:
- weight
- lift
- drag
- thrust
As the velocity of a fluid (gas or liquid) increases, its pressure decreases. This is known as__________ ___________.
Bernoulli’s Principle
The angle at which a stall occurs is called the_____ __________ ___ __________
critical angle of attack
________ __________ is the uncorrected reading obtained from the airspeed indicator.
Indicated airspeed
_________ _______ is indicated airspeed corrected for installation and instrument error.
Calibrated airspeed
___________ _________ is calibrated airspeed corrected for temperature and pressure variations.
True airspeed
_______ ________ is the altitude read on the altimeter after it is set to the current local altimeter setting.
Indicated altitude
____ _______ is the height above the surface.
Absolute altitude
______ ________ is the true height above Mean Sea Level (MSL) normally measured in feet.
True altitude
________ _________ is the altitude that is indicated whenever the altimeter setting dial (Kohlsman window) is adjusted to 29.92.
Pressure altitude
________ _______ is the pressure altitude corrected for nonstandard temperature and/or pressure.
Density altitude
An aircraft may not be operated unless, within the preceding ______ calendar months, it has had an annual inspection and has been approved for return to service
twelve
In addition, when operating within the lateral boundaries of the surface area of Class B, C, D or E airspace designated for an airport, the ceiling must not be less than _________ feet. If the pilot intends to land, take off, or enter a traffic pattern within such airspace, the ground visibility must be at least _____ miles at that airport.
1,000
3
