ATK Flashcards
(124 cards)
1
Q
- At ISA -9 what will your altimeter read:
A
a. Over read. Note: Pressure is lower due to the lower temperature so the altimeter will be over reading
2
Q
- What happens to the ETP if you have a headwind component on the outbound leg?
A
a. The ETP will move towards the aerodrome of destination.
The position of the ETP will always move into wind, away from the mid point.
3
Q
- What is EAS corrected for?
A
a. Indicated
Position/pressure
Calibrated
Compressibility
Equivalent
Density
True
4
Q
- What happens to the difference between IAS and TAS with an increase in altitude?
A
a. Increase
5
Q
- Equivalent still air distance formula
A
ESAD (nm)=Total dist/GS x TAS
(Think of the V=d/t formula. Time is represented by GS x TAS)
6
Q
- What happens to TAS if climbing at a constant M. no.?
A
a. If an aircraft maintains Mach number, TAS reduces when an aircraft climbs. This is because air density (and consequently, the speed of sound) decreases with altitude. Therefore, Mach number, being the same part of a now lower value, is reached.
7
Q
- If you climb at a constant IAS, your limiting speed will eventually be
A
c. MMO, Limiting mach number.
Maximum Mach Number (MMO): Preventing Your Wing From Going Supersonic.
As you climb, the true airspeed to reach MMO decreases. In sub-sonic jets, MMO prevents you from reaching your critical mach number. That’s the speed where some air flowing over your wings begins traveling at the speed of sound.
8
Q
- Aircraft maintains a constant IAS in the climb, what happens to TAS & LSS (Local speed of sound)?
A
a. Constant IAS – TAS will increase & LSS will decrease
9
Q
- How does temperature affect the speed of sound?
A
a. The speed of sound is directly proportional to the square root of the absolute temperature (the speed of sound will increase with an increase in temperature).
LSS = 38.94√K
At sea level ISA: LSS = 661kts.
At 35,000’ ISA: LSS = 575kts.
10
Q
- Airspeed in the climb – at a constant TAS / IAS / Mach No. what do each do?
A
a. Constant IAS – Both TAS & Mach No. increase
Constant Mach No – Both IAS & TAS decrease
Constant TAS – Mach No. increases, IAS decreases
11
Q
- Cruise Mach No. is more limiting when
A
The higher the aircraft flies
12
Q
- What happens to the speed of sound with altitude / temperature
A
a. LSS reduces with altitude and with cooling temperatures
13
Q
- What errors does a Mach Meter NOT suffer from?
A
a. Density error & Compressibility error.
14
Q
- The two capsules in a Mach Meter are what?
A
a. Airspeed
Altitude calibration.
15
Q
- MFS is
A
b. Free stream Mach number – airflow unaffected by the aircraft
16
Q
- Ml is
A
a. Local Mach number – is the speed of air relative to the Local Speed of Sound measured at a point on the aircraft
17
Q
- In a single spool turbine, what is the RPM compared to turbine speed?
A
a. Same
18
Q
- In a single spool turbine engine, the speed of the compressor and turbine rotate at?
A
a. Same speed as turbine
19
Q
- Compressor stall / surge is
A
a. A reverse flow of air through the engine caused by unstable air
20
Q
- Symptom of compressor surge
A
d. An engine popping or banging noise and/or vibration
Rapidly rising turbine temperature
Fluctuating engine rpm,
Fluctuating fuel flow,
Engine thrust will rapidly decrease.
21
Q
- What does N1 mean?
A
a. “N” followed by a number is the rotational speed and number in the sequence of a spool.
22
Q
- What does TOT mean?
A
a. Turbine outlet temperature
23
Q
- What does ITT mean?
A
a. Interstage turbine temperature
24
Q
- What does TET or TIT mean?
A
a. Turbine entry temperature, turbine inlet temperature.
25
Regarding turbine engines, the LP compressor is connected to the ...?
a. The LP compressor is connected to the LP turbine (fan)
26
25. On a 3 spool gas turbine engine, the N1 is referred to as the;
a. RPM of the low pressure compressor fan.
27
26. What is the advantage of the 3 spool engine?
It has greater efficiency over a wider range of operating conditions.
Each spool can be rotated at its optimum design speed. It is also less noisy and easier to start.
The front spool sections rotate slower and thus achieve better reliability.
Improved stall/surge characteristics, better response, more exact rpm control, and higher compression ratios.
28
27. What are the symptoms of a hung start?
Engine rpm does not increase at a normal rate, and/or engine fails to reach idle rpm.
You will see an EGT (exhaust gas temp) rise, but the rpm will hang.
A hung start is normally due to a start generator malfunction, such as cutting too early, to insufficient fuel flow, or to some malfunction of the compressor inlet guide vanes or bleed valves, leading to excessive back pressure through the compressor stages.
29
28. A constant speed drive does what?
a. Mechanical gearbox that takes an input shaft rotating at a wide range of speeds, delivering this power to an output shaft that rotates at a constant speed, despite the varying input. Keeps electrical output at X amount and constantly despite varying input rpm.
A CSD runs off the accessory case and drives the AC generator at a constant RPM regardless of engine RPM. CSDs ensure that all generators are producing acceptable outputs of constant frequency, voltage, and phase, and allows each generator to be paralleled and to share the aircraft’s electrical load.
30
29. What is bypass ratio?
a. It is the ratio of air that does not enter the turbine section of the engine to the ratio that does. I.e, if 10 parts of air does not enter the engine and 1 part does, the engine has a 10:1 bypass ratio.
31
30. Why are high bypass engines more efficient then low bypass engines?
High bypass engines moves a large mass of air and accelerates it to a reasonably high speed. This is most efficient up to quite high mach numbers.
Low bypass engines move a smaller amount of air but accelerate it to a lot high speed. This is only efficient at very high mach numbers.
The high bypass engine is thus more efficient and achieves a lower Specific Fuel Consumption (lb of fuel / lb of thrust / per hour)
Also high bypass engines are less noisy.
32
31. Engine bleed air has what effect?
a. EPR decreases (engine pressure ratio)
EGT increases
Thrust decreases
33
32. What is cabin differential pressure?
a. Difference between ambient pressure and cabin pressure
34
33. If an aircraft is cruising at FL300 and the Cabin Altitude is increased from 4000ft to 6000ft. What is the effect on pressure differential?
a. Decreases
35
34. Cabin pressure is controlled by?
a. Outflow valve.
Airplanes control their cabin pressure via an outflow valve. This valve helps keep the incoming air inside the cabin and then releases it at a rate that is regulated by pressure controllers.
36
35. Cabin pressure reaches max differential, what happens if the aircraft climbs?
a. The cabin will climb
37
36. ASI requires what input?
a. Pitot and static
38
37. If you are in a climb and your static ports become blocked, what will your altimeter do
P S
C O U
D U O
a. Under read
39
38. Pitot tube is blocked in cruise, aircraft enters a descent what happens to ASI
P S
C O U
D U O
a. under read
40
39. Blocked pitot tube on your ASI in the climb, will it overread or underread
P S
C O U
D U O
a. ASI will over read
41
40. What is Gyro wander?
a. Due to the gyros rigidity, the spin axis of a perfect gyro should continue in a fixed direction. Any movement away from this direction is known as gyro wander.
42
41. What is real wander?
a. Is the wander caused by the movement of the spin axis due to imperfections and friction
43
42. What is apparent wander?
a. Is due to the apparent movement of the gyro axis due to the rotation of the earth. Corrected for by a drift nut/latitude rider.
44
43. What is a space gyro
a. Free to move in all planes
45
44. What is a tied gyro
a. A space gyro with freedom of movement in three planes, but tied to one reference. Used in the direction indicator.
46
45. What is an earth gyro?
a. Spin axis is perpendicular to horizon. Used in artificial horizon
47
46. What is a rate gyro?
a. Freedom of movement in only one plane, used in turn coordinator
48
47. How is hydraulic fluid pressurised (I don’t recall this being on cram)
?
49
48. What is the function of a hydraulic accumulator?
a. To store hydraulic fluid under pressure
50
49. How is the hydraulic pump cooled
?
51
50. What lubricates a hydraulic pump?
?
52
51. VMCA question. Make sure you know the angle of bank that is used when aircraft manufacturers work out VMCA.
a. Maximum angle of bank 5*
53
52. What does VMCA mean?
a. The minimum speed, whilst in the air, that directional control can be maintained with one engine in operative (critical engine on two engine aeroplanes), operating engine(s) at takeoff power and a maximum of 5 degrees of bank towards the good engine. 1.2 x Vs.
54
53. Does a jet aircraft have a critical engine?
a. Only on take-off in crosswinds. A four engine type, such as the boeing 747-400 obviously has the outer engines give more yaw if they fail due to moment arm.
Nil in head wind
The most upwind engine in x-wind due to increased yaw if engine fails (weather cocking)
55
54. What is the critical engine on a propeller aircraft?
a. On a propeller aircraft with conventionally rotating propellers, the critical engine is the left outboard engine, conversely with propellers rotating anti-clockwise, the outboard right engine would be critical. Counta/contra-rotating propellers do not have a critical engine.
With conventionally rotating propellers, the down-going blade on each engine has a greater angle of attack producing more lift (thrust) thus offsetting the thrust line on each engine to the right. The right engine (on conventionally rotating propellers) has a greater arm to the C of G causing greater yaw, making the left engine critical.
56
55. How does crosswind affect the critical engine?
a. On a propeller driven aircraft, a crosswind from the opposite side to the critical engine will assist the situation because the yaw required to offset that which is produced by the failure of the critical engine will be assisted by the effect of the crosswind (weathercocking).
The reverse situation will make matters worse. Crosswind from the same side as the critical engine will require even more demand from the rudder. The yaw produced by the failure of the critical engine will be compounded by the effect of the aircraft weathercocking.
57
56. What does an inverter do?
a. Regulate the flow of electrical power. Fundamentally, an inverter accomplishes the DC-to-AC conversion by switching the direction of a DC input back and forth very rapidly. As a result, a DC input becomes an AC output.
58
57. What is and causes thermal runway on a battery?
a. Thermal runaway occurs when the temperature inside the battery reaches the point that causes a chemical reaction to occur inside the battery. Can be caused by overcharging, or excessive loading.
59
58. Function of a rectifier
a. Converts AC-to-DC current
60
59. What is included in basic empty weight
a. Empty aircraft, unusable fuel, full oil, specified equipment in the flight manual.
61
60. What is basic operating weight?
a. Aircraft prepared for service (APSW)
Basic empty weight + pilot + crew, crew baggage, food, water. Max all up weight minus payload and fuel).
62
61. What is maximum zero fuel weight?
a. The maximum permissible weight of an aircraft with no disposable fuel or oil. (Basic operating weight, plus payload. Everything except the fuel)
63
62. What is ramp weight?
a. Zero fuel weight, plus fuel. The maximum gross weight permitted prior to taxi. May exceed the MAUW by the weight of the fuel to be burnt off for start and taxi.
64
63. What is MTOW
a. Maximum take off weight, The weight specified as the maximum take-off weight of the aircraft in a flight manual or airworthiness certificate.
65
64. Given figures for fuel on board, burn, ZFW, landing weight, max take-off weight and their max limits how much more fuel can we up lift? Determine what’s most limiting and see if you can put more on.
66
65. Definition of ASDA?
a. Accelerate-stop distance available means the length of the take-off run available plus the length of any stopway.
67
66. ASDA is calculated using
a. Distance to accelerate to V1 – 1 sec recognition – 2 sec transition phase – distance to bring aircraft to a stop
68
67. Definition of stopway?
a. A defined rectangular area on the ground at the end of the take-off run available prepared as a suitable area on which an aircraft can be stopped in the case of an abandoned take-off.
69
68. Define take-off run available?
a. The length of the runway declared by the aerodrome operator as available and suitable for the ground run of an aeroplane taking-off. TORA
70
69. Define take-off distance available?
a. The length of the take-off run available plus the length of any clearway. TODA (Runway + clearway)
71
70. What is e relationship between TORA and TODA?
a. TORA – Useable length of the runway, it DOES NOT take into account of any clearway or stopway.
b. TODA – Useable length of the runway PLUS any declared certified clearway.
72
71. A balanced field
a. Is when the TODA is EQUAL to the ASDA
73
72. Define clearway?
a. A defined rectangular area on the ground or water, at the departure end of the runway – under the control of the aerodrome operator, or with agreement of the authority controlling the clearway – selected or prepared as suitable area over which an aeroplane may make a portion of its initial climb to a specified height 35ft.
74
73. What is ASDA?
b. TORA + stopway available
75
74. VLOF
a. Is limited by max tyre speed/VMBE (maximum braking energy)
76
75. Define landing distance available? (draw picture)
a. The length of the runway that is declared by the aeroplane operator as available and suitable for the ground run of an aeroplane. LDA
77
76. What is dynamic aqua (or hydro) planning
a. Occurs when the water lifts your wheels off the runway. This usually happens when a wedge of water builds up in front of your tires and lifts them off the runway.
78
77. What is viscous aquaplaning?
a. Arises in the same way as dynamic aquaplaning, but only on abnormally smooth surfaces such as touchdown zones contaminated with excessive rubber deposits, where it may begin and continue at any ground speed.
79
78. What is reverted rubber aquaplaning?
a. It occurs when the pilot brakes heavily on wet runways, causing the wheels to lock and tires to skid. The heat generated by friction causes one or more tires to revert to their uncured state (melt).
80
79. What is the formula for aquaplaning?
9√of the tire pressure
Non-rotating 7.7 x tyre pressure
81
80. Hydro planning (aquaplaning) is affected by the following factors
a. Tyre pressure
Runway surface
Tread depth
Tyre speed
Water depth
Runway grooving
82
81. Question about auto brakes on landing. The answers were very wordy and along the lines of
a. Apply brake pressure which gives a constant rate of deceleration
83
82. Vents in the fuel tank are used to
a. Vent to atmosphere relieve both vacuum and pressure
84
2. What impact does a forward CoG have on your aircraft?
Forwards CoG means the tail will be producing a downwards force, acting in the same direction as weight. This means more lift is required to overcome the combine weight and tail force down vectors, which is achieved by increasing the AoA. With an increased AoA, you create more induced drag. This will increase fuel burn, and decrease climb performance.
Decrease ROC
85
3. What effect does a forward C of G have on stability and control effectiveness?
a. Increased stability, worse RoC
86
2. What effect does a balanced field have on take-off performance
a. A balanced field means that it is critical that an abort is carried out immediately on EF recognition. Also that the t/o on one engine could be marginal if continued as a balanced field is a take off right on the performance limits for the given aircraft weight – not a favourable scenario
87
3. Effect of adding flap on Max T/O weight for a distance limited T/O and Obstacle limited T/O
a. Increasing T/O and decrease AoC
88
4. Adding a stopway to a balanced field, what happens to V1 and TOW of a runway limited take off?
a. Increased take-off weight and increased V1 as ASDA increases
89
5. When compared to a balanced field takeoff, if a clear way is added to the TODA what effect does that have on your takeoff. Weight, V1 TODR
a. Higher takeoff weight with a lower V1
90
6. What happens to V1 + MAUW when an ASDA is added to a balanced field length
a. Increase V1 and increase weight
Looking at the stopway alone, a longer stopway gives you a longer ASDA, i.e. the TORA + stopway. This allows a higher V1 speed to be selected (and therefore a higher takeoff weight), because you have a longer distance available to stop.
91
7. A down-sloping runway has what effect to V1?
a. Reduces V1
92
8. In a runway limiting scenario Adding extra flap for takeoff has what impact
a. Increase takeoff weight but reduced max climb weight
93
9. If the flaps are extended from 5 degrees to 15 degrees, what affect will this have on V2?
b. Decrease (V2 is 1.2vs, think of V2 like how the factors effect stall speed)
94
10. Definition of V1
a. Means the maximum speed in the takeoff at which the pilot must take the first action (eg. Apply brakes, reduce thrust, deploy speed brakes) to stop the aircraft within the accelerate stop distance available; and
b. Also means the minimum speed in the takeoff, following the failure of the critical engine at VEF at which the pilot can continue the takeoff and achieve the required height above the takeoff surface within the distance available.
c. Must be:
i. Greater than or equal to VMCG
ii. Less than or equal to VR
iii. Less than or equal to VMBE
95
11. For V2 over-speed take-offs, what are the obstacle considerations?
a. Close in obstacle clearance reduced
b. Distant obstacles clearance better due higher speed.
96
12. What is the advantage of an increased V2?
a. Improved climb gradient
b. An increase in take-off weight
97
13. VR is never less than
a. V1
b. MCA
98
14. Definition of V2
a. The airspeed at which the aircraft complies with those handling criteria associated with the climb after takeoff and the target speed to be attained at the 35’ screen height, assuming recognition of an engine failure at or after V1 and used to the point where acceleration to flap retraction speed is initiated.
Must be:
i. Greater than or equal to 1.2 VS
ii. Greater than or equal to 1.1 VMCA
99
15. Definition of VMCG:
i. Is the minimum speed on the ground during the take off run, at which it is possible to recover control of the aircraft with the use of primary aerodynamic controls and the takeoff can be continued safely, when the critical engine suddenly becomes inoperative, with the remaining engines at takeoff thrust.
100
16. What is Critical Mach Number?
a. It is the lowest mach number where the airflow over any part of the aircraft first goes supersonic (reaches the speed of sound).
101
17. What happens when the Critical Mach Number is reached?
a. A shockwave may form which increased drag, reduces lift, moves the centre of pressure, and can cause buffeting.
At the shockwave, the velocity falls but the pressure temperature, and density all increase. More pressure equals less lift – more drag.
As the mach number is increased above the critical mach number, the shockwave becomes more developed and moves backwards.
102
18. Why does the aircraft tend to pitch nose down when the Critical Mach number is reached? (Mach Tuck)
a. Here are three reasons.
The shockwave on the upper surfaces upsets the lift distribution chordwise and causes the centre of lift to move rearwards.
The swept wing tends to experience shock wave effect first at the wing root because this is thickest and has higher angle of incidence. This causes a loss of lift inboard and thus forwards.
The shockwave can cause a reduction in downwash over the tailplane.
103
19. What would you do to recover the aircraft from a MMO overspeed?
a. Deploy the speed brake, roll the aircraft level, hold back elevator pressure, a=use the elevator/stabiliser trim in small amounts. Power levers may be close depending on the aircraft type. I.e. 747 – 400 low thrust line – Closing power levers will reduce thrust causing more pitch down.
104
20. What is a Mach Trimmer?
a. It is a device fitted to some Jet aircraft which trims the stabiliser up at mach numbers exceeding MMO. It is used because some aircraft experience either lack of elevator effectiveness or very heavy elevator forces at high mach numbers above MMO.
105
21. What happens to cruise speed and drift down alt with decrease in weight?
a. Increases cruise speed and increased drift down alt
106
23. The IRS is considered a standalone unit, because?
a. does not require any external navigation input, own internal sensors
107
24. Why is an INS considered a self contained system?
?
108
25. Where does the RNAV approach wind vector needle get its data?
a. IRS + ADC.
109
27. The aircraft’s aerodynamic ceiling is
a. The point at which the high airspeed mach buffet and low speed stall buffet merge
110
28. The aerodynamic ceiling of the aircraft is known as
a. Coffin Corner (A/C can not be made to go faster or slower)
111
29. The maneuver envelope must be
a. At an altitude and airspeed sufficient to avoid stalling and slow enough to avoid structural damage
112
30. What is the definition of Part 121?
a. Pax configuration of more than 30 seats (excluding crew member seats)
Payload capacity of more than 3410 Kg
113
31. The purpose of Part 119
a. Is to prescribe the certification requirements for operators to perform Air Operations and the operating requirements for the continuation of this certification. Air Operations include Air Transport Operations (ATO) and Commercial Transport Operations (CTO).
114
32. The purpose of Part 121
a. Is to prescribe the operating requirements for air operations of aeroplanes that have a passenger seating configuration of more than 30 seats, excluding any required crew member seat, or a payload capacity of more than 3410 kg, carried out by the holder of an Airline Air Operator Certificate issued under Part 119 of the Rules.
115
33. What is RVSM?
a. Reduced Vertical Separation Minimum.
116
34. ETOPS
Extended Range Twin Engine Operations
a. ETOPS stands for Extended Range Twin Engine Operations and is the term used to govern regulations and procedures pertinent to twin engine commercial aircraft operating on extended global or domestic routes with poor off track alternates. The basic premise regarding this topic is related to the concept of redundancy and failures of the powerplant/hull. The basis of ETOPS is the improved engine reliability shown by new age aircraft.
The rules state that any aircraft with two engines must be capable of flying to an adequate airport where it can land safely within 90 minutes at normal cruise speed or 60 minutes at single engine cruise speed (in still air conditions). It the aircraft can not comply with the above regulation – it is then required to become an ETOPS rated aircraft
With an ETOPS rating, this rule is extended up to 90mins, 120mins, 138mins and 180mins
Individual aircraft must be specifically authorised. As new aircraft are introduced to the fleet a proving period is implemented at 120 min before a higher classification is considered.
Air New Zealand currently operates B737 on 120min ETOPs and B767 on 180 min ETOPs. However when suitable alternates exist it for 120 min ETOPS it may be advantageous to operate to this criteria as opposed to 180 min. These advantages are in the area of MEL dispatch and minimum fuel reserves to be carried.
The ETOPS times stipulated simply determine the single engine time in still air from which an aircraft must remain from a suitable alternate.
117
35. Rate of vertical descent depends on
a. Angle of glide & airspeed
118
36. Aircraft in a constant descent @ 300kts, how does weight affect glide angle?
a. The heavier the aircraft the earlier descent must commence. So the more shallow the glide angle.
119
37. Reduced thrust take offs are used when
a. There is a long runway available
MTOW is low
120
38. Two methods of reduced thrust takeoffs are
a. Fixed derate (ie 10% - 20%)
Assumed temperature
121
39. Using an assumed temperature RT take off what speed corrections are there
a. V1 is reduced to allow for slower acceleration but other speeds are the same for the actual TOW
122
40. An increase in engine RPM results in
a. Higher mass air flow
SFC decreases
Higher temps
Thrust output increases
123
41. Two ways of measuring thrust are
a. EPR (the ratio of inlet pressure and turbine exit pressure)
N1 (low pressure rotor speed)
124
42. Reverse thrust is most efficient
a. At high aircraft speeds
