問題一覧
1
What is the definition of mach number?
TAS/speed of sound
2
What is the definition of critical mock number?
The airplane indicated mock air speed when a point on the upper wing surface will reach a local mock air speed of 1.0
3
Select the true statement regarding shockwaves on the wing air foil
Shockwave formation is quite common blown, indicated air speed of mock 1.0
4
What is one of the reasons why shockwaves increase drag?
The boundary layer becomes turbulent and begins to separate from the air foil surface behind the shockwave formation, so parasite drag increases
5
As the aircraft accelerates to reach the drag rise mock number also called the first divergent mock number select two correct statements concern concerning this situation
At this mach, there is a significant rise in the coefficient of drag, At this mach, there is a substantial decrease in the coefficient of lift
6
What is the true statement regarding a characteristic of high altitude flight called Mach Buffett
This condition occurs at high mock numbers due to shockwave intensity, causing boundary layer separation
7
Which situation explains when mock Tuck happens and the result
As the aircraft increases air speed to approach, Mcrit and the result is a nosedown pitching moment
8
What is the protection system installed on all transport aircraft to control the effects of mock tuck?
Mock trim system
9
shockwaves can result in loss of Elon effectiveness due to flow separation behind the shockwave and head of the aileron
true
10
Regarding a Sweetback wing versus a straight wing, what is the effect of the coefficient of lift of the sweet back wing at the same angle of attack as the straight wing?
A swept wing will produce a lower CL than a straight wing
11
In cruise flight the sweep back wing will ____ compared to a straight wing
Be able to cruise at a higher air speed because of a higher critical mock number
12
Which of the following is a true characteristic of a swept wing versus a straight wing in the approach and landing phase of transport aircraft
Swept wing, maximum coefficient of lift is reduced so takeoff and landing air speeds must increase
13
Airframe structural limitations of an airplane are defined by two flight parameters that have maximum lifts, which are
Maximum indicated airspeed and maximum limiting load factors (g load)
14
Which is the true statement regarding the assumptions for limiting load factor
LLFs maximum G limits to protect against structural damage of the air frame and Flight
15
What are the true characteristics of the ultimate low factor also known as the ultimate stress limit select two that are true
ULF is the G load at which catastrophic structural failure may occur, ULF must succeeded the limit load factor by 150%
16
If the aircraft represented in fig 14.6 was flying at 200 KIAS enrolled into a 60° bank turn maintaining level of constant speed flight. It would exceeded its positive limit load factor.
false
17
Flying at or below maneuver speed, the aircraft cannot be overstressed with full elevator, deflection in one direction
true
18
What is the reason for FAR 25 to require a guest envelope for G load certification?
Wind gusts or turbulence and high air speeds may cause structural damage so design limits are required
19
What is the definition of VMO/MMO
Maximum operating IAS or mock number that may not be intentionally exceeded
20
Which is the true statement regarding VMO/MMO
All of the above are true
21
Low speed buffet boundary is defined as
A minimum safe airspeed where the onset of a pre-star buffet starts as the boundary layer begin separation as AOA increases
22
High-speed buffet boundary is defined as
Onset of buffet caused by turbulent airflow, separation behind shockwaves on the wings
23
Select the two correct cruise speed effects after climbing to a higher cruise altitude
IAS for the high-speed buffet boundary will decrease, IAS for the low speed buffet boundary will increase
24
positive static stability is defined as the Initial tendency of an aircraft after the original displacement from the equilibrium state the initial reaction will be
To return to the equilibrium position
25
Positive dynamic stability is defined as an aircraft is displaced from equilibrium then the aircraft reacts with
an oscillatory motion that decreases displacement towards equilibrium over a long time.
26
After an aircraft has been displaced a dampened oscillation is one that demonstrates
Both positive static and positive dynamic stability
27
An aircraft is said to be in a state of equilibrium if the sum of all moments enforces at its center of gravity or equal to zero list, the three aircraft axes were forces produce airplane rotations about the center of gravity
vertical longitudinal lateral
28
An aircraft is said to be in a state of equilibrium if the sum of all moments enforces at its center of gravity are equal to zero. List, the four forces acting on the airplane.
weight lift thrust drag
29
What transport aircraft component has the primary purpose of compensating for the large movement in CG location which can cause various longitudinal pitching moments
Horizontal stabilizer trim
30
Select the true statement regarding CG location in the wings contribution to pitch stability
A CG forward of the aerodynamic center of the wing results in more pitch stability
31
An aircraft is trimmed for non-side slip, Flight and then a subjected to a new gusting relative wind from the right which reaction will indicate positive static directional yaw stability
The aircraft will react with a yaw to the right into the gusting, relative wind, decreasing sideslip angle
32
What aircraft component has the greatest influence on directional yaw stability
Vertical stabilizer
33
If a gust subjects the aircraft to a sideslip, what is the reaction of the aircraft that is needed to show positive lateral roll stability
Aircraft rolling moment toward wings level
34
Which is a physical characteristic of the digital design of a wing
Wing with upward inclination from the wing root to the tip
35
An aircraft with wing dihedral encountering a sideslip condition will contribute to positive static lateral roll stability because
The down wing in the direction of sideslip were result in more left than the opposite rising wing in the aircraft roll wings level
36
Sweep back wings ___ lateral roll stability compared to straight wings
increase
37
Which is two flight control systems on large transport aircraft operate for lateral roll control
ailerons spoilers
38
Normally yaw Can produce role thus if a pilot of a stable airplane applies right rudder the airplane will
yaw to the right and roll to the right
39
Dutch roll is a couple directional yaw and lateral role oscillation that can be very serious. What aircraft component has been made mandatory equipment for transport category air aircraft to prevent this condition.
yaw dampers
40
Transport aircraft stability at high cruise altitudes has a significant difference versus low altitudes. Select the true statement regarding high altitude stability.
All three aircraft axes have a reduced restoring force and oscillation dampening force at high altitudes
41
A sweep back wing platform will begin to stall first at the
aft wing tip area
42
As the angle of attack is steadily increased, what happens to the airfoils boundary layer?
The turbulent BL area spreads from the trailing edge forward towards the leading edge and will eventually separate from the wing
43
What is the function of vortex generators on the upper wing surface?
To re-energize the boundary layer and delay airflow separation
44
At approximately the stall angle of attack is where the air foil will
Produce the maximum coefficient of lift
45
select the two variables that will increase the thrust available of a turbo jet engine on takeoff assumption is that throttles are set at maximum takeoff thrust And all other factors remain constant, except the variable specified in the answers
Decreased ambient air temperature, Engine inlet cross-sectional area is increased
46
What is the calculated ratio to achieve maximum specific range of an aircraft at a constant altitude weight and best specific range air speed
Maximum ratio of TAS/fuel flow
47
While flying out a particular cruise altitude list three pilot actions regarding a change in flight that will increase jet engine fuel efficiency, which is all about increasing the specific range of the airplane
Increase air speed with headwind, Decrease air speed with tail wind, Increase airspeed with high altitudes
48
Specific fuel consumption, which is a measure of jet engine efficiency is the ratio of
lbs fuel per hour/thrust
49
Referred to the handout fig 6.8 according to this thrust required drag curve what is the KTAS that will attain the minimum drag
250 KTS
50
How does the extension of trailing edge flaps on a swept wing airplane affect the stall angle of attack compared to the flaps up configuration
Decreases the stall angle of a attack