单选题 About the Mach number. which of the following statement is incorrect?
A、The Mach number is higher,more difficult the air compression
B、Mach number increases,then the air more compressed easily
C、The Mach number is a measure of the air compressed
单选题 A symmetrical airfoil will generate( )lift at positive angle of attack.
A、zero
B、positive
C、negative
单选题 A swept wing has a tendency to stall first at the ()
A、wing root,with the stall progression toward the wingtip.
B、wingtip,with the stall progression toward the wing root.
C、all of the rear parts on the wing.
单选题 ()makes the object tend to return to the original equilibrium state.
A、the stable moment
B、the damp moment
C、the friction moment
单选题 ()is the primary cause of high-speed buffet.
A、Vortex Generators
B、shock stall
C、wave drag
单选题 A jet aeroplane is climbing at constant Mach number below the tropopause. Which of the following statements is correct?
A、IAS increases and TAS increases
B、IAS decreases and TAS decreases
C、IAS increases and TAS decreases.
单选题 ()is usually installed in each tank for fuel quantity indication of modern aircraft.
A、A float type fuel gauging system
B、A capacitance-type fuel gauging system
C、A direct reading mechanical fuel measuring system
单选题 ()can prevent the tip of swept wing from first stall.
A、geometric torsion
B、trim tab
C、winglet