Prog 1 Excel Tester.xlsm - Propeller System Flashcards
1
Q
On Engine NO. 1 & 4, the NTS system is activated by what SHP:
A
-150 to -500 SHP
2
Q
On Engine NO. 2&3, the NTS system is activated by what SHP:
A
-100 to -500 SHP
3
Q
Normal RPM Limits
A
96.3-99.1%
4
Q
- What is the Sequencing priority for the autofx system?
A
4-1-3-2
5
Q
At what time does the Back-up valve open?
A
When Coord. Is below 28º
6
Q
Offspeed Propellers – (Overspeed or Underspeed)
A
An RPM indication in excess of 1 per cent above or below normal governing RPM and detected audibly is considered an offspeed. This malfunction may be caused by the SYNC system or the propeller governing system.
7
Q
Fx Valve/NTS Check Light (Cause)
A
Cause: Fx valve is functioning properly during an inflight restart. Light is on steady when e-handle is pulled
8
Q
What requirements are necessary to activate the (TSS) autofeather system?
A
- System must be armed (switch on );
- power lever greater than 60 deg coord;
- THRUST drops below 500 lbs
- no feather buttons in
9
Q
Stby Prop Pump 2 output
A
40qt/min
10
Q
What does ‘Prepare for Pitchlock’ mean?
A
It means increase airspeed and altitude to that required to safely make your destination in anticipation of the propeller pitchlocking
11
Q
The inner shaft on the torquemeter is connected to both the power section & the RGB, while the outer shaft is connected only to the pwr section. Why?
A
The inner shaft is connected at both ends, and is twisted when pwr is applied. The outer shaft is connected at only one end and is not twisted. The deflection between the 2 shafts gives us a SHP reading
12
Q
List 2 ways that pitchlock can be actuated.
A
- Loss of controlling prop fluid pressure;
- Overspeed of 103.5 % rpm
13
Q
What are the two main categories of propeller malfunctions?
A
Featherable and Non-Featherable
14
Q
In flight the beta follow up system acts to(x3):
A
1.acts as a low pitch stop above 72 Deg Coord;
2.prevent overspeed in response to rapid power lever movement;
15
Q
Airstart speeds if range is critical
A
A maximum of 345 KIAS at sea level, reducing 6 KIAS/1000 feet, should be used if range is critical.
16
Q
What are the rpm limits for low rpm?
A
71.0 - 73.8 %
17
Q
At what RPM does the pitchlock system engage?
A
103.5%
18
Q
Mechanical Methods to Feather prop x2
A
- Negative Torque System;
- E-Handle
19
Q
What is the danger associated with the prolonged operation of a decoupled propeller with the power section shutdown?
A
The RGB could be starved of oil in as little as 30 minutes, resulting in a fire or possible prop separation
20
Q
Auxiliary Fx pump Normal Power Sources
A
(AC) 3 Phase AC Power Bus = B A A B;
(DC) Control DC Power Mon EX EX Mon;
Alter AC Power Bus A 1 & 4
21
Q
BETA Light
A
indicates the B/A is less than 10 degrees or less ; serves as a visual confirmation that the B/A is decreasing as the power levers are retarded towards reverse.
22
Q
What is the danger associated with E-handling a pitchlocked propeller?
A
Without enough controlling fluid to fx the prop the teeth will disengage momentarily allowing CTM to drive the prop to a finer blade angle. This reduces max possible airspeed and altitude and therefore range.
23
Q
What are the 2 purposes of the interconnecting structure?
A
- transmits pwr from the engine to the RGB
- aligns & supports the engine & the RGB
24
Q
Why does pitch lock stop at 57º BA?
A
To allow for feathering
25
CHIPS light
indicates that metal particles are flowing through the oil system of either the RGB or the Engine or both.
26
Which component is used to electrically actuate the three methods of electrically feathering the prop
Feather Valve Solenoid
27
What are the 2 subsections of the prop control assembly & where are they located?
1. valve housing - at the top
2. pump housing - at the bottom
28
38.In the flight range, the RPM is controlled by:
Prop Governor
29
PCO for __ seconds before air start allows the feather pump to _________________________and verifies operation of the ___________________________
PCO for 10 seconds before air start allows the feather pump to re-pressurize the prop Dome and verifies operation of the Feather Solenoid Valve
30
all four AutoFx Lights illuminated (Cause)
AutoFx is armed in all Four engines.
31
NTS Check Light Indicates:
NTS has occurred; will remain steady on
32
Takeoff RPM limits to allow for an over/undershoot
96-106%. Stable within 10 seconds.
33
What components comprise the interconnecting structure between the power unit and the RGB (x3)?
a. the torquemeter
b. 2x tie struts
c. Safety Coupler
34
When OAT is LESS THAN -10 degree C (x3)
1. conduct normal engine starts
2. monitor engine oil temp until 40 deg
3. do not move power levers from start position until engine oil temp is 40 deg C
35
Power Levers are restricted from being retarded into the ground range in flight by two means
1. A physical Ramp in the Power Level Quadrant
2. The Flight Idle Stop
36
What items make-up the Prop Governor? (x4)
1. Fly weights
2. Pilot valve
3. Servo valve (spool
4. Speeder springer
37
What are the rpm limits for normal rpm?
96.3 - 99.1 %
38
When power levers are below 28 deg coord & blade angle is above 10 deg, a pitchlock reset solenoid allows up to _____ rpm, to avoid pitchlock when the power lever is retarded very rapidly into ground range and the blade angle decrease is slow
109 % rpm
39
The safety coupler will disconnect the engine from the prop in cases of extreme drag when ______ SHP is reached.
-1700
40
What is the 45-deg airstart protection system?
A backup for a failed NTS during in-flight unfeather operations. At 45 deg B/A, the feather solenoid valve is energized and de-energized cyclically to optimize the airstart blade angle.
41
When is the 45 deg airstart protection available? (x3)
Feather Button held in the UNFTHR position
Pressure Cutout Overide (PCO) button not depressed
Blade angle less than 45 degrees
42
How can you tell if a propeller is pitchlocked or not?
RPM will follow power lever movement
43
When would you ‘Prepare for Pitchlock’?
When you are faced with a propeller malfunction not adequately covered by one of the Propeller Procedures or at any time you believe there is a possibility a propeller might pitchlock.
44
Electrical functions of E-handle (2F BEO)
(F) Feather valve solenoid (actuates
(F) FCU (shuts off fuel
(B) Bleed air shutoff valve (Closes
(E) EDC (dump) Firewall shutoff valve(Close
(O) Oil tank Shutoff Valve (Close)
45
In the ground operating range, blade angle is controlled by _______.
Power lever(Coord) position
46
Fx Cutout Switch cam in the beta shaft prevents px surges from terminating the fx process until
B/A reaches 74 Deg or more
47
What is the definition of an RPM fluctuation?
An RPM Fluctuation is a sustained cyclic RPM oscillation which can be detected audibly and is possibly followed by corresponding fluctuations of TIT, SHP, or fuel flow.
48
Mechanical Functions of the E-handle (3F Gen)
(F) FCU (shutoff
(F) Fx Valve (mechanically moves it to the Fx position
(F) Fuel Tank Emergency Shutoff Valve (closes
(GEN) Generator Cooling Air Shutoff Valve (Closes)
49
Max reverse is equal to what coordinator position ? What blade angle?
0 degrees coord / - 13 degree blade angle
50
Outside the range of pitchlock allows for what?
Unfeathering ( Pitchlock cammed out in the ground range)
51
normal rpm Limits (Ground):
96.3 - 99.1 %
52
What are the Prop Fx Pump power sources?
B-A-A-B
Alt A for 1 and 4
Mon-Ex-Ex-Mon
53
What 2 features are available with the sync servo switch in the normal (on) position? (x2)
1. Anticipation circuitry - limits rpm transients caused by rapid power lever movement
2. Speed derivative circuitry - limits rpm transients caused by changes in power plant load
54
Explain the ASR relationship?
TAS + SHP = Inverse relationship
TAS + RPM = Positive relationship
55
What is purpose of the RGB?
Coverts the engine high rpm low torque energy, to low rpm high torque energy that can be used by the prop
56
What is the minimum blade angle for Beta follow-up at 90º Coord
22.5 º
57
The prop’s response to an overspeed condition is to ( increase / decrease ) blade angle.
Increase
58
Flight Idle Stop Solenoid is Powered by the
Mon Essential DC Bus
59
How can the failure of a tach generator affect the RGB?
The tach generator gearing is co-located with that of the EDC (on 2 and 3) and the RGB oil pump. Be aware that the failure of a tach generator could lead to a complete failure of the RGB and that indications such as an EDC dumping or oil pressure fluctuations could indicate impending disaster!
60
Feather Cutout Engages when the dome px reaches what PSI?
600-800 PSI
61
Feather button Light (Cause)
Cause: indicates feather pump relay is closed supplying electrical power ot the feather pump. Possible internal leakage, incomplete feather cut-out circuit, Pump U/S
62
True or False: The RGB oil system is completely independent of the power section oil section.
False : They share a common sump (supply)
63
What is the purpose of the barrel assembly?
It is the structural foundation for the prop blades
64
Three Things that happen when you push the Feather Button (x3)
1. Energizes Fx valve Solenoid
2. Energizes Fx Pump
3. Shuts off Fuel at the FCU
*Can also be electrically actuated by the E-hand and the Thrust Sensitive System*
65
What is the range of coordinator;
0º - 90º
66
low rpm Limits (Ground):
71.0 - 73.8 %
67
Ground start is equal to what coordinator position ? What blade angle?
15 degrees coord / 0 degrees blade angle
68
What is the range of Blade Angle:
-13º – 86.65º
69
Main Prop pump 1 output
20qt/min
70
Feather Button Light
indicates the Feather Pump Relay is energized (the Feather Pump Motor may or may not be running)
71
Main and stby regulator valve ensures that pump manifold pressure is
150 PSI above demand pressure, to counter CTM
72
Airstart recommended speeds
170 KIAS minimum, 210 KIAS maximum.
73
What is the first warning associated with the Offspeed Propeller Check?
If an overspeed is accompanied with either PROP PUMP light, or if RPM is in excess of 103.5%, carry out the Non-Featherable Pitchlock Propeller Check.
74
Name the shaft that controls pwr lever & E-handle inputs to the prop (gnd range).
Alpha shaft
75
What does the Fuel Governor & Prop Pitchlock switch do when set to TEST?
It resets the prop governor’s onspeed condition to 106%. This will act to reinforce the engaged pitchlock teeth
76
Low RMP Limits
71-73.8%
77
The low pitch stop mechanically limits blade angle to a minimum of _____ in flight.
13 degrees
78
What determines whether a propeller is featherable or not?
The amount of control fluid remaining
79
What are the rpm limits for max reverse?
96.7 - 104.9 %
80
Pitchlock engaged when (x2)
1. loss of controlling oil pressure
2. overspeed of 103.5 % rpm
81
What is the function of the feather valve solenoid?
When energized, it hydraulically positions the feather valve to the full feather position
82
Symptoms of a misadjusted pitchlock regulator: Retarding the powerlever causes rpm to ___________ ; forward movement causes rpm to __________________; continued movement forward causes horsepower to _______________ while rpm____________________.
Symptoms of a misadjusted pitchlock regulator: Retarding the powerlever causes rpm to decrease ; forward movement causes rpm to return to 100 percent; continued movement forward causes horsepower to increase while rpm maintains 100 %.
83
What could cause a propeller to Fail to Fx?
Could be caused by early cut-out of the fx pump, fx pump motor failure, or possibly low fluid levels.
84
NTS is cammed out below ____ degrees coordinator and is not required for_______
NTS is cammed out below 24 degrees coordinator and is not required for ground operation
85
True or False : The NTS system prevents the prop from driving the engine.
TRUE
86
What is the main force that acts on the prop in the flight range?
CTM
87
Rpm Normal Governing limits in flight
100% +/- 1% ( 99.0 - 101 % )
88
Electrical methods to feather prop x3
1. E-Handle
2. Thrust Sensitive System (Auto-Fx
3. Feather Button
89
NTS INOP Light indicates:
NTS has failed and is not available during AirStart.
90
True or False : By selecting normal rpm ( via the rpm selection paddle ), you can change the prop blade angle.
False : Rpm selection simply adjusts spring tension on the FCU, which adjusts fuel flow, which sets RPM
91
What is the ASR principle?
TAS increase – SHP decreases – RPM increases
92
PP1 and PP2 Annunciator Light
indicate possible internal leak or inadequate prop fluid quantities.
93
one AutoFx Lights illuminated (Cause)
Prop thrust has dropped below 500 lbs thrust and prop automatically feathers
94
Safety Coupler ensures gearbox/engine separation At:
-1700 SHP
95
What does turning the Sync Servo OFF do?
It removes electro-mechanical governing from the propeller
96
If, during static ( ground ) cycling of the propeller, motion from the fx position to a lower blade angle is interrupted, the propeller shall __________ before attempting any further blade angle decrease.
If, during static ( ground ) cycling of the propeller, motion from the fx position to a lower blade angle is interrupted, the propeller shall be fully re-feathered before attempting any further blade angle decrease.
97
What is the range of pitchlock?
17º – 57º BA
98
flight idle rpm Limits (Ground):
94.5 – 98.4 %
99
29. Do not cycle props statically ( on gnd ) if the OAT is ___________________ until engine oil temp is ________________________. ( external leakage may occur due to hardened o-rings )
29. Do not cycle props statically ( on gnd ) if the OAT is less than 0 deg C until engine oil temp is above 0 deg C. ( external leakage may occur due to hardened o-rings )
100
What is Synchrophasing?
Electronic Governing System that augments the propeller governing system.
101
List some of the benefits that the Aurora gains by using a Turboprop.
a. Significant reverse thrust capability
b. Smaller turbine for equivalent thrust
c. More efficient at low altitude, slow speeds
d. Instantaneous power response
102
Flight Idle Stop Solenoid can be overcome by
12lbs if it fails to retract
103
What type of prop does the Aurora have?
T-56A constant speed / variable pitch Hydro-mechanical
104
How is a decouple due to prop failure recognized?
0 SHP
550 TIT
600 pph
an overspeed condition
105
3 Important Scavenge components in the RGB
1. Main Scavenge Pump
2. nose Scavenge Pump
3. Magnetic Drain Plug
106
Sync Servo system will send a signal to ____ to compensate for rapid movements
Anticipation potentiometers.
107
Beta followup system acts as the _______ in flight
hydraulic low pitch stop in flight.
108
EDC oil is cooled by engine oil using an _______________________
EDC oil is cooled by engine oil using an oil-to-oil heat exchanger
109
Components in the RGB Accessory Drive Assemly (STOOGE)
S tarter
T achometer Generator (is its own power sorts)
O il Pump
O il Filter
G enerator
E DC (engine Driven compressor)
Chips Detector
110
The barrel assembly is the ____ of the propeller. It serves as the ____________________ for the propeller blades, the dome, and the control assemblies.
The barrel assembly is the hub of the propeller. It is mounted on the propeller drive shaft at the front of the reduction gear assembly. It serves as a structural foundation for the propeller blades, the dome, and the control assemblies.
111
RGB Input low torque/high RPM __________ and Outputs high torque/low RPM ________
RGB Input low torque/high RPM 13820 and Outputs high torque/low RPM 1020
112
Overall Reduction Ratio of RGB
13.54:1
113
Does the RGB share an oil supply or is it independent?
Shares an oil supply with power section
114
List the 4 assemblies of the prop
Barrel Assembly
Dome Assembly
Control Assembly
Cowling Assembly
115
List the two Parts to the control assembly
valve housing
pump housing
116
4 Propeller Safety Features
45 degree AIRSTART Protection
BETA Follow-Up
Pitchlock and Pitchlock Reset
Low Pitch Stop (Hydraulic and Mechanical)
117
Function of Speed Set CAM
Sets 100% rpm in the flight range. It compresses the speeder spring below flight idle, so that the blade angle is controlled by power lever position.
118
Function of BETA Set CAM
Working in conjunction with the BETA Follow-Up CAM on the BETA shaft, it selects blade angle in the BETA range and provides BETA Follow-Up in the flight range.
119
Feather and Disarm CAM
Positions the feather valve to feather when the emergency shutdown handle is pulled and repositions the NTS linkage so as to not actuate the feather valve below 24 degrees coordinator.
120
Function of ALPHA Backup CAM
Opens the backup valve below approximately 28 degrees coordinator to provide extra decrease pitch pressure to retract the low pitch stop.
121
Function of ALPHA Pitchlock Reset CAM
Energizes the Pitchlock reset solenoid below 28 degrees coordinator provided the blade angle is greater than 10 degrees.
122
Function of BETA Follow-Up CAM
Works in conjunction with the BETA Set CAM to set the blade angle in the ground range and provides BETA Follow-Up in the flight range.
123
Function of BETA Backup CAM
Opens the backup valve above approximately 24 degrees blade angle. It closes the backup valve at blade angles below 24 degrees to prevent decrease pressure great enough to break the low pitch stop from developing.
124
Function of BETA Airstart CAM
Energizes the feather valve solenoid below 45 degrees blade angle when the feather button is being held out.
125
Function of Feather Cut-Out Switch CAM
Prevents pressure surges from terminating the feather circuit until blade angle reaches 74 degrees or more.
126
Function of Pitchlock Reset and BETA light CAM
De-energizes the Pitchlock reset solenoid when the blade angle drops below 10 degrees and illuminates the BETA light.
127
List the 4 Components of the Prop Governor
Flyweight Assembly
Pilot Valve
Servo Spool
Speeder Spring
128
•Maximum Reverse Blade Angle
-13 deg (hydraulic)
129
•Ground idle Blade Angle
-6 deg
130
•Start Blade Angle
0 deg
131
•Flight Idle Blade Angle
13 deg
132
•Minimum at T/O Pwr Blade Angle
22.5 deg
133
•Feather Blade Angle
86.65 deg
134
•Pitchlock range Blade Angle
17 to 57 deg
135
As the power lever is moved from 0 to 34 degrees coordinator control cams move the B/A from reverse (____ deg B/A) through flat pitch (START) to____ deg.
As the power lever is moved from 0 to 34 degrees coordinator control cams move the B/A from reverse (-13 deg B/A) through flat pitch (START) to +11 deg.
136
What does CTM tend to do to the prop? INCREASE or DECREASE pitch
Decrease
137
Blade angle or BETA is sensed off what blade?
#1 Blade
138
What shafts are in the valve housing?
Alpha and beta Shafts
139
What three things action the Feather Valve
E-handle
NTS
Feather valve solenoid
140
Positioning the Feather Button manually to FX causes what? (x3)
Energizes the Feather Valve Solenoid.
Energizes the Aux Feather Pump.
Shuts off fuel at the FCU.
141
What does the 45 degree Airstart protection circuitry do?
It is a system that restricts B/A to a minimum of 45 degrees while the Feather Button is held out. This is to protect against runaway propellers
142
If these conditions are met the Airstart Control Relay is energized:
NTS INOP light illuminates
Feather Valve Solenoid is energized
Prop B/A increases towards FX
143
45º air start backs-up what safety device?
Negative Torque Sensing (NTS)
144
Why and for how long do we push PCO?
10 seconds - Allows feather pump to re-pressurize the dome and verifies operation of the feather valve solenoid.
