module 9 propellers Flashcards
a propeller is a mechanical devise to convert BHP into?
THP -trust horse power
the factor to enables a propeller to produce trust is?
the decrease on pressure created on the back of the propeller
the flat side of the blade is called?
propeller blade face
what is geometrical pitch on a propeller?
the theoretical distance that the propeller moves por each RPM with any loses
the forward distance that the a propellers moves during one revolution is know as?
effective pitch
define slip
the losses in efficiency of the propeller
slip=geometrical pitch - effective pitch
what is the greatest force acting on the propeller ?
centrifugal force
on what part of the propeller is the most stress imposed
the hub made of high grade steel
what is the portion of the propeller blade that is nearest to the hub ?
blade shank
what is pitch distribution?
the gradual twister of the propeller blade from the hub to the tip of the propeller - to equalize the center of pressure
why does the blade angle from the hub to the tip
to compensate the increase of velocity from the hub to the tip - to equalize the center of pressure
the normal tendency of the propeller blade when it rotates is?
go fine pitch as CTM is grater than ATF
the aerodynamics forces acting on a propeller in cruise RPM tend to?
Move the propeller to coarse pitch- ATF to coarse
the blade angle in a propeller fixed pitch stays the same during the flight. the angle of attack of the blade does what as the aircraft forward speed increases?
the angle of attack decreases
the forces that bend the propeller blades in the direction of the travel are called
trust bending forces
