Avit 323 Block 10 Exam: Thrust UPDATED
Exam Questions and CORRECT Answers
thrust - CORRECT ANSWER - -must be generated to overcome the natural resistance of
drag
-newton's third law
>"for every action there is an equal and opposite reaction"
unaccelerated - CORRECT ANSWER - means the airplane neither speeds up or slows
down, but remains at a constant velocity
accelerating - CORRECT ANSWER - if thrust is greater than drag, the speed would
increase - as speed increases so does drag - it will build until it equals the new drag and we will
once again be unaccelerated
deceleration - CORRECT ANSWER - initially drag is greater than thrust (speed), but as
we slow drag decreases until it reaches equilibrium with thrust
propellers: rotating airfoil - CORRECT ANSWER - subject to stalls, induced drag, and
other troubles that affect airfoils
thrust equation - CORRECT ANSWER - newton's second law of motion
f=ma
propeller driven airplanes - CORRECT ANSWER - large mass of air accelerated to
relatively low final velocity
propeller: thrust available - CORRECT ANSWER - -propeller is an airfoil
-not 100% efficient
-produces induced and parasite drag
, -affected by airflow disturbed by other blade
increase in forward velocity - CORRECT ANSWER - -angle of attack of blade decreases
-thrust decreases
fixed pitch prop - CORRECT ANSWER - peak efficiency at one airspeed
constant speed prop - CORRECT ANSWER - -more blade settings
-greater range of efficiency
reciprocating aircraft engine - CORRECT ANSWER - -power producing machine
-fuel flow directly proportional to power output
Output Power of an Engine: PLANK - CORRECT ANSWER - P-indicated effective
pressure (psi)
L-length of stroke in ft or fractions of ft
A-area of the cylinder (sq. in.)
N-number of power strokes per min
K-number of cylinders
non-geared, direct drive engine - CORRECT ANSWER - BHP = SHP
thrust horsepower - CORRECT ANSWER - power that is imparted by the propeller to the
air
Propeller efficiency - CORRECT ANSWER - always less than 100%
power = - CORRECT ANSWER - force x velocity
Exam Questions and CORRECT Answers
thrust - CORRECT ANSWER - -must be generated to overcome the natural resistance of
drag
-newton's third law
>"for every action there is an equal and opposite reaction"
unaccelerated - CORRECT ANSWER - means the airplane neither speeds up or slows
down, but remains at a constant velocity
accelerating - CORRECT ANSWER - if thrust is greater than drag, the speed would
increase - as speed increases so does drag - it will build until it equals the new drag and we will
once again be unaccelerated
deceleration - CORRECT ANSWER - initially drag is greater than thrust (speed), but as
we slow drag decreases until it reaches equilibrium with thrust
propellers: rotating airfoil - CORRECT ANSWER - subject to stalls, induced drag, and
other troubles that affect airfoils
thrust equation - CORRECT ANSWER - newton's second law of motion
f=ma
propeller driven airplanes - CORRECT ANSWER - large mass of air accelerated to
relatively low final velocity
propeller: thrust available - CORRECT ANSWER - -propeller is an airfoil
-not 100% efficient
-produces induced and parasite drag
, -affected by airflow disturbed by other blade
increase in forward velocity - CORRECT ANSWER - -angle of attack of blade decreases
-thrust decreases
fixed pitch prop - CORRECT ANSWER - peak efficiency at one airspeed
constant speed prop - CORRECT ANSWER - -more blade settings
-greater range of efficiency
reciprocating aircraft engine - CORRECT ANSWER - -power producing machine
-fuel flow directly proportional to power output
Output Power of an Engine: PLANK - CORRECT ANSWER - P-indicated effective
pressure (psi)
L-length of stroke in ft or fractions of ft
A-area of the cylinder (sq. in.)
N-number of power strokes per min
K-number of cylinders
non-geared, direct drive engine - CORRECT ANSWER - BHP = SHP
thrust horsepower - CORRECT ANSWER - power that is imparted by the propeller to the
air
Propeller efficiency - CORRECT ANSWER - always less than 100%
power = - CORRECT ANSWER - force x velocity
