MH-60R - Systems - AFCS Flashcards
(108 cards)
0
Q
What are the 3 main subsystems of the AFCS?
A
The stability augmentation system (SAS), the stabilator system, and the Advanced Flight Control Computer (AFCC).
Each system operates independent of the others, but each compliments the others.
1
Q
What does the AFCS do?
A
It is an electrohydromechanical system that provides inputs to the flight control system to assist the pilot in maneuvering and handling the helicopter.
2
Q
What are the features provided by the AFCS?
A
- Pitch, roll, and yaw stability augmentation.
- Stabilator control
- Cyclic, collective, and pedal trim
- Pitch and roll attitude hold
- Airspeed hold
- Heading hold
- Barometric altitude hold
- Radar altitude hold
- Pitch and roll hover augmentation/gust alleviation
- Turn coordination
- Maneuvering stability
- Automatic approach to hover
- Hover coupler
- Automatic depart
- Crew hover
- Blade-fold assist
- Automatic preflight check
- Diagnostics (failure advisory)
- Cable angle hover
3
Q
What is the central component of the AFCS?
A
The digital AFCC
4
Q
What does the AFCC do?
A
It commands the SAS actuators and trim actuators in all 4 control channels and provides self-monitoring, fault isolation, and failure advisory.
5
Q
What are the 2 types of control provided by the AFCC?
A
Inner-loop (SAS) and outer-loop (autopilot)
6
Q
What does the inner-loop do?
A
It employs rate damping to improve dynamic helicopter stability. This system is fast in response, limited in authority, and operates without movement of the flight controls.
7
Q
What does the outer loop do?
A
Provides long term inputs by trimming the flight controls to the position required to maintain the selected flight regime. It is capable of driving the flight controls through their full range of travel, or 100% authority, at a limited rate of 10% per second.
8
Q
How can the pilot override both inner and outer loop functions?
A
By making normal flight control inputs
9
Q
Where are correction signals sent?
A
Inner-loop: SAS actuators
Outer-loop: Trim actuators
10
Q
Where is the AFCS voltage sensor rely mounted?
A
On the forward side of the cockpit canted bulkhead
11
Q
What does the AFCS VSR do?
A
It is designed to select the source of the single phase, 115 VAC, phase B power to be applied to the AFCC by controlling the AC Essential Bus Relay (K8). Normally the AC Essential bus is powered by the No. 1 Primary bus. If the voltage being sensed is within tolerance, the VSR energizes and the AC Essential bus relay is energized to provide AC power from the No. 1 AC Primary bus to the AFCC. If the voltage is not within tolerance, the VSR deenergizes and the AC Essential Bus and the AFCC are powered from the No. 2 AC Primary Bus.
12
Q
What does the Stabilator system do?
A
It optimizes trim attitudes for cruise, climb, and autorotative flight, and provides redundant pitch stability augmentation to complement the SAS. It is completely independent of the other 2 AFCS subsystems except for common airspeed sensors, lateral accelerometers, collective position sensor, and pitch rate gyros.
13
Q
Describe the stabilator system.
A
It is an automatic fly-by-wire control system with a manual backup slew control. It has 2 electric jack screw actuators, acting in series, to position the stabilator. Each actuator provides one-half the input to position the stabilator and is controlled by a separate, redundant stabilator amplifier.
14
Q
What is the primary purpose of the stabilator system?
A
To eliminate undesirable nose-up attitudes caused by rotor down wash impinging on the horizontal stabilator during transition to a hover and low-speed flight.
15
Q
What is the warning regarding stabilator failure without the associated light?
A
It is possible for the stabilator to fail without illumination of the STABILATOR caution light and associated aural warning tone. In this case, the first indication of failure will be an uncommanded pitch change.
16
Q
Describe the Stabilator Control panel buttons and their functions.
A
AUTO CONTROL push button: used to engage the automatic mode or to reset the stabilator in the event of a failure.
MAN SLEW switch: by moving the switch, the pilot can manually position the stabilator either stabilator limits.
TEST push button: operational below 50 KIAS and is used to check the automatic mode fault detector.
17
Q
What is the range of the stabilator?
A
It travels from 42 degrees trailing-edge down for hover and low speed flight (below 30 KIAS) to 10 degrees trailing-edge up for cruise and maneuvering flight.
18
Q
How are the electrical screw actuators powered?
A
Through the DC essential bus and STAB SYS PWR cb and the No. 1 DC Primary Bus and STAB PWR cb respectively.
19
Q
What are the four inputs required to position the stabilator?
A
- Collective position - decouples aircraft pitch response when collective position is changed.
- Lateral acceleration - decouples the aircraft pitch response during changes in tail rotor lift in side slip conditions.
- Airspeed - aligns the stabilator with the main rotor down wash during low-speed flight.
- Pitch rate - supplements the dynamic stability provided by the SAS and AFCC.
Both pitch rate and lateral acceleration inputs improve the dynamic response of the aircraft, especially in gusty air conditions.
20
Q
What receives the 4 inputs to position the stabilator? How does it work?
A
The stabilator amplifiers receive the 4 inputs from independent sensors. The AFCC monitors these sensors for malfunctions. The stabilator system constantly monitors and compares the position of the two actuators. Any system malfunction caused by a difference in the 2 stabilator actuator positions will result in a automatic power shutdown to both actuators, a warning tone to all crew members, and appearance of the STABILATOR caution.
21
Q
How does the MAN SLEW switch work?
A
It bypasses the stabilator amplifier automatic mode and applies power directly to the actuators through relays in the amplifiers. The stabilator position indicator assists the pilot in manually slewing the stabilator to a desired position.
22
Q
How will total travel of the stabilator be restricted in the event of an actuator failure?
A
Stabilator travel is restricted to 35 degrees if actuator fails in the full-down position and 30 degrees if it fails in the full-up position.
23
Q
What does the SAS system do?
A
It provides improved stability by sensing acceleration rate in the pitch, roll, and yaw axes and applying a control input to dampen out the sensed rate.
24
What is the difference between SAS 1 and SAS 2?
SAS 1: Analog
SAS 2: digital system that is part of the AFCC.
They have identical functions except SAS 2 also has hover augmentation/ gust alleviation and altitude hold/coupler features.
25
What amount of control authority is provided by with both SAS channels engaged?
Pitch, roll, and yaw actuators have +/-10% control authority, with each channel providing +/-5%.
26
The Collective Inner-Loop Actuator is only commanded by what?
SAS 2
27
With what modes engaged does the collective SAS operate?
RADALT, BARALT, APPR/HVR, and DEPART. It's limited to +/-10% control authority.
28
How is hydraulic pressure supplied to the SAS actuators?
Through the SAS shutoff valve on the pilot-assist module. Operation of the shutoff valve is provided through the SAS/BOOST pushbutton on the AFCS control panel. SAS actuator pressure is monitored by the SAS pressure switch; a loss of pressure will cause the SAS caution to appear.
29
How are inputs provided to the SAS actuators?
For each control axis(except vertical), command signals from both SAS channels are applied simultaneously to separate coils of an electrohydraulic servo valve. The two signals are summed to provide a single input into the flight control system through a single-series SAS actuator. The operation of both SAS channels is continuously monitored by the AFCC.
30
What happens if either SAS channel malfunctions?
The AFCS degraded caution will appear and the appropriate SAS fail advisory light on the AFCS CONTROL panel will illuminate. If SAS 2 has failed, the AFCC will automatically disengage the affected axis. If SAS 1 has failed, the pilot must manually disengage SAS 1 using the AFCS CONTROL panel. The remaining operable SAS channel is limited to +/-5% authority! but operates at twice it's normal gain to compensate for the failed SAS channel.
31
When does the SAS caution appear?
Whenever SAS 1 or SAS 2 lose electrical power (manual disengagement or power sever) or when hydraulic pressure is lost to the actuators.
32
What dies the TRIM system use to move the flight controls?
2 high-torque electric servos for the yaw and collective axes and 2 hydraulic servos for the pitch and roll axes.
33
What do the parallel trim actuator assemblies do?
They provide the flight control force gradients, detent positions, and outer loop autopilot control functions.
34
How much command authority do the trim actuators have?
They have full command authority in all 4 control axes, but are rate limited to 10% per second.
35
What does depressing and releasing a trim release button do?
Depressing the trim release disengages the respective trim function and allows free control motion. Releasing a trim release reengage so the trim.
36
How does one disengage yaw trim above 50 KIAS? Below 50 KIAS?
Above 50 KIAS: the pedal micro switches and collective TRIM REL button must be pressed simultaneously.
Below 50 KIAS: only the pedal micro switches have to be pressed.
37
What happens if the trim system fails?
The TRIM advisory light will illuminate on the AFCS control panel. The pilot is able to override the trim control forces in all axes.
38
What does the Autopilot do?
It maintains helicopter pitch and roll attitude, airspeed, and heading during cruise flight and provides a coordinated turn feature at airspeeds above 50 KIAS.
39
How is the autopilot engaged? Disengaged?
It is engaged by depressing the SAS 1 or SAS 2 pushbutton, the TRIM pushbutton, and then the AUTO PLT pushbutton. It is disengaged by depressing the AUTO PLT pushbutton.
40
How are attitude and airspeed hold engaged?
Attitude hold: Airspeed below 50 KIAS and AUTO PLT pushbutton is depressed.
Airspeed hold: Airspeed above 50 KIAS, angles of bank less than 30 degrees, and AUTO PLT pushbutton depressed.
41
How are attitude changes made with Attitude hold engaged?
They are commanded by changing the cyclic position with the TRIM REL button or use of the four-way TRIM switch. Using four-way trim movement, the helicopter attitude will change at a rate of 5 degrees per second. When four-way trim movement is stopped, the autopilot stabilizes the helicopter at the new cyclic position and attitude.
42
How is airspeed changed with Airspeed hold engaged?
Actuating the four-way trim switch will initiate cyclic movement and cause the helicopter to change airspeed reference at a rate of 6 KIAS per second.
43
How does the autopilot account for airspeed changes due to gusts, winds, etc.?
It uses integrated longitudinal acceleration for short-term corrections, and an airspeed sensor for long-term updates.
44
How does the roll attitude hold feature work?
Attitude information is supplied to the AFCC from both EGIs and a command signal is sent to the roll SAS and trim. When the four-way trim switch is actuated laterally, the helicopter rolls at a rate of 6 degrees per second.
45
How does the automatic wing-leveling capability work?
During transitions from a hover to airspeeds above 50 KIAS, this feature automatically returns the aircraft from a left roll attitude in a hover to a wings-level attitude at 50 KIAS. Once a level attitude is established, the attitude hold feature holds this attitude until the pilot commands a new roll attitude.
46
What provides the Heading hold feature in flight?
The yaw trim actuator.
47
How is Heading Hold engaged?
By depressing the AUTO PLT pushbutton with weight off wheels.
48
How does the heading hold feature work?
Releasing the tail rotor pedal micro switches at a given heading synchronizes the trim system on the established heading. A potentiometer in the yaw trim actuator sends a trim position feedback signal to the AFCC and cancels the drive signal at the desired position by stopping the actuator.
The autopilot uses a collective position sensor to establish reference heading during yaw excursions caused by main rotor torque changes. Collective/airspeed-to-yaw electrical mixing is controlled through the collective position sensor and an airspeed signal that reduces left yaw as airspeed increases.
49
How does the HDG TRIM switch on the collective work?
With heading hold engaged, the HDG TRIM switch on the collective allows heading changes without retrieving. Below 50 KIAS the aircraft is slewed at 3 degrees per second. Above 50 KIAS, actuation of the switch for less than 1 second provides a 1 degree heading change and actuation for greater than 1 second provides a 1 degree per second coordinated turn.
50
How is heading hold disengaged? Reengaged?
Disengaged: weight on wheels.
Reengaged: following a turn, when the following conditions are maintained for 2 seconds:
1. Aircraft roll attitude is within 2 degrees of wings level.
2. Yaw rate is less than 2 degrees per second.
51
How is Altitude hold selected?
By selecting either BAR ALT or RAD ALT on the AFCS control panel
52
How does altitude hold work?
The AFCC uses the existing altitude from either the air data transducer (BAR ALT hold) or the radar altimeter (RAD ALT hold) as a reference altitude. The AFCC commands both the collective SAS actuator and collective trim actuator to maintain the reference altitude. The computer also monitors engine torque and will stop increasing collective in the event that torque reaches or exceeds 106% above 80 KIAS or 120% below 80 KIAS. This occurs whenever the autopilot is positioning the collective.
WARNING:
Uninterrupted use of the four-way cyclic trim switch to increase speed may cause the aircraft to enter a descent with altitude hold engaged without an associated caution light. Manual input is required to arrest the descent.
53
How does BAR ALT hold work?
It may be engaged at any altitude and airspeed by depressing the BAR ALT pushbutton with SAS 2, TRIM, and AUTO PLT engaged. Depressing the collective TRIM REL switch temporarily disengages BAR ALT hold with a simultaneous flashing BAR ALT pushbutton. Upon release of the switch, barometric altitude hold automatically reengage sand maintains the altitude at the time of reengagement. Because of noise in the barometric altitude rate signal, short-term rate is obtained from the integrated vertical acceleration. Long-term corrections are obtained from the barometric altitude sensor.
54
How does RAD ALT hold work?
It is engaged at any altitude from 0-5,000 feet AGL and at any airspeed by depressing the RAD ALT pushbutton with SAS 2, TRIM, and AUTO PLT engaged. Depressing the collective trim rel switch temporarily disengages RAD ALT hold. RAD ALT hold will automatically reengage at the altitude at which the collective trim rel switch is released. In the hover coupler mode, altitude hold is referenced to the altitude selected on the AFCS control panel HVR ALT knob. The RDR ALT pushbutton will flash if RADALT hod, is engaged with the collective trim rel switch depressed. In the hover coupler mode, transition from one altitude to another is made with the HVR ALT knob. Resulting climb/descent rates are limited to 1,000 and 200 feet per minute, respectively.
55
What happens if RAD ALT hold mode fails?
BAR ALT hold mode is automatically engaged. Integrated vertical acceleration provides short-term radar altitude corrections and rate information from the radar altimeter altitude signal provides long-term updates.
56
How does hover augmentation/gust alleviation work?
It is provided by SAS 2 and further improves aircraft stability at low airspeeds by using attitude retention, longitudinal acceleration, and lateral acceleration to eliminate drift.
57
How does turn coordination work?
It is provided at airspeeds above 50 KIAS and allows the pilot to fly a coordinated turn with directional control provided by the AFCS. The autopilot uses lateral acceleration and roll rate to determine if the aircraft is out of balanced flight and provides the yaw SAS and trim with the necessary inputs to maintain a coordinated turn. Automatic turn coordination is engaged and heading hold disengaged when aircraft roll attitude is greater than 1 degree and any of the following conditions exist:
1. Lateral cyclic displacement is greater than 3%
2. Cyclic TRIM REL button is pressed.
3. Roll attitude exceeds 2.5 degree bank angle using the four-way trim switch.
58
How does the maneuvering stability feature work?
The cyclic is displaced forward by the longitudinal trim actuator to increase the pilot effort required to maintain a given pitch rate at bank angles greater than 30 degrees. The higher pitch control forces alert the pilot to g-loading during maneuvering flight. The liner longitudinal cyclic force is provided by commanding 1% forward cyclic for each 1.5 degree AOB between 30 and 75 degrees AOB. This feature is engaged with the AUTO PLT pushbutton.
59
How does the automatic approach to hover feature work?
Automatic approach can be initiated at any airspeed and altitude lower than 5,000 feet AGL by activating the automatic approach pushbutton (APPR/HVR) on the AFCS control panel. The aircraft assumes a wings-level attitude whenever APPR is selected and again at 80 KIAS during the approach.
WARNING
Initiating an automatic approach while in a trimmed turn may result in a spiraling approach that will continue through the selected altitude. Immediate pilot action will be required to avoid water impact.
60
What is the capability of the automatic approach to hover feature?
It allows the aircraft to perform an automatic approach to any longitudinal or lateral groundspeed selected, using the LONG VEL and LAT VEL knobs.
61
Describe the automatic approach to hover profile.
On approach profile and greater than 40 KIAS, the deceleration rate is 2.5kts/sec and descent rate is 215 fpm. Less than 40 KIAS the deceleration rate is 1.5kts/sec and the descent rate is 130 fpm.
Above approach profile, airspeed is held constant and descent rate is 360 fpm until on profile.
Below approach profile, RAD ALT hold is engaged and and deceleration is 2.5 KTS/sec until on approach profile.
62
How can the deceleration rate be varied?
It can be varied up to +/-1 knot per second using the four-way trim switch. Aft trim increases the deceleration rate, forward trim decreases. Amount of change depends on duration of trim input. A full 2 second input results in the full 1 knot per second change. The normal approach profile is automatically reset passing through 40 KGS. Remainder of the approach can be adjusted through longitudinal trim. The normal profile can be reset by depressing the cyclic TRIM REL button.
63
What does the hover coupler feature provide?
It provides lateral and longitudinal groundspeed control, stabilization about the selected groundspeed, and altitude retention.
64
How much can the longitudinal and lateral groundspeed be adjusted?
+/-10 KTS using the four-way trim switch.
65
When is the hover coupler mode engaged?
Automatically at the termination of an automatic approach to a hover or it can be manually engaged when the aircraft is hovering by pressing the APPR/HVR pushbutton on the AFCS control panel with SAS 2 and AUTO PLT engaged. It will engage when the longitudinal groundspeed is within 1 KGS of selected LONG VEL after an automatic approach or within 5 KGS if engaged manually.
66
What type of altitude hold is engaged for a coupled hover? When?
RAD ALT hold is engaged automatically when the aircraft altitude is within 2 feet of the altitude selected on the HVR ALT switch.
67
What's being monitored during a coupled hover?
Dual engine torque is being monitored by the AFCC and will stop increasing collective if torque reaches or exceeds 116%.
68
What does pressing and releasing the cyclic TRIM REL button do during a couple hover?
It removes the four-way trim inputs, returning the aircraft to the LONG VEL and LAT VEL knob settings on the AFCS control panel.
69
What makes short-term and long-term corrections for the hover coupler?
Short-term longitudinal and lateral groundspeed is obtained from integrated longitudinal and lateral acceleration, long-term corrections are obtained from the EGIs.
70
What is the Note associated with the hover coupler?
NOTE
During a coupled hover in high winds, it is possible to indicate airspeeds greater than 50 KIAS. Under these conditions, if cyclic trim release is activated, heading hold will be disabled, and at bank angles greater than 2 degrees, turn coordination will be enabled. This amh result in a rapid deviation from the desired hover heading.
71
Describe the automatic depart feature.
It provides the capability to perform an automatic departure from a coupled hover or from an automatic approach to an airspeed of 120 KIAS and an altitude of 150 feet AGL.
72
What does the DEPART HOV button on the cyclic do?
It departs a coupled hover or aborts an automatic approach. The green DPRT light will illuminate on the AFCS control panel.
73
When is the automatic depart feature available?
Anytime autopilot is engaged, airspeed is below 50 KIAS, and RADALT hold is operable.
74
What happens during an automatic departure?
The aircraft beings to accelerate to 120 KIAS and climb to 150 feet AGL. Passing through 50 KIAS, the aircraft assumes a wings level attitude if AOB is 5 degrees or less. If bank angle is greater than that, the aircraft will maintain a coordinated turn for the established bank angle. During the departure, the AFCC monitors dual engine torque and will stop increasing collective if torque reaches or exceeds 106% above 80 KIAS or 120% below 80 KIAS. At a rd alt altitude of 150 feet, the RADALT hold automatically engages.
75
What happens if DEPART HOV is selected a second time on the cyclic?
It terminates both climb and acceleration and engages RADALT hold. If above 50 KIAS, airspeed hold is engaged; below attitude hold is engaged. Pressing the cyclic trim rel button terminates acceleration and provides airspeed or attitude hold. Pressing the collective trim rel switch terminates the climb and provides RADALT hold.
76
Describe the crew hover feature.
It allows the aircrewman to position the helicopter while the aircraft is in a coupled hover. The aircrewman controls the aircraft using the HOVER TRIM CONTROL panel. The hover trim grip has a control authority of +/-5 KGS laterally and longitudinally about the reference values selected on the LONG VEL and LAT VEL switches in addition to the speed set by the four-way cyclic trim switch.
77
How is the crew hover feature activated?
From the AFCS control panel by depressing the CREW HVR pushbutton. It can only be activated if the hover coupler mode is already engaged.
78
Describe the sonar cable angle control signals feature.
Cable angle sensors mounted on the reeling machine provide the AFCS with signals that are proportional to the angle of the cable relative to vertical when the helicopter is in a stable hover. The cable angle signals are utilized by the AFCS to maintain the cable perpendicular to the water. Each time the transducer is stopped while being raised, the cable angle signals are decoupled from the AFCS by the Reeling Machine Indicator Unit (RMIU) for a delay of 6+/-2 seconds. Sonar cable deflection is measured longitudinally (pitch) and laterally (roll) from the sonar reeling machine as DC signals. One set of signals is sent to the AFCS to establish a stable sonar mode hover to maintain the helicopter directly over the point of sonar entry into the water. Another set of signals is sent to the mission displays, providing cable information in the hover mode.
79
What does the Cable Angle Desensitizer (CAD) do?
It prevents erratic helicopter movement due to waves set in motion along the transducer cable.
80
What does The Cable Angle Hover Mode Feature do?
It provides a coupled hover over the sonar transducer during sonar dipping operations.
81
When is Cable Angle Hover Mode engaged? Disengaged? Overridden?
Engagement is indicated when the CABLE ANGLE-ON legend on the SONAR CABLE ANGLE control panel and the ENGAGED light on the SO CABLE ANGLE CONTROL panel go on. It is disengaged automatically whe. The sonar transducer is reeled up through the 27+/-12 foot water depth, or when the pilot presses the CABLE ANGLE pushbutton switch. Disengagement leaves the helicopter in coupled hover mode. An OVERRIDE pushbutton switch on the SONAR CABLE ANGLE control panel allows the pilot to defeat the 27+/-12 foot water depth requirement for the sonar transducer.
82
Describe the Blade Fold feature.
The AFCS positions the cyclic, collective, and tail rotor pedals prior to the blade-fold sequence. The AFCC commands the trim actuators to drive the flit controls to a predetermined position. When the controls reach the blade fold position, the electromechanical pitch-lock actuators are engaged to lock the pitch change horns. After all pitch locks have engaged, the blade-fold sequence commences.
83
Describe the Automatic Preflight Checks feature.
The AFCC provides an automatic preflight check if the SAS components prior to flight. The automatic preflight check is initiated, using the SAS 1 pushbutton, when the following conditions are present:
1. Weight on wheels
2. Rotor brake on
3. Engine torques below 10%
4. Both EGI attitudes valid.
5. SAS 1 pushbutton engaged (after AFCC on for at least 20 seconds)
If any of the above conditions are changed, the AFCC CMOTR/PWR RESET button must be cycled and 20 seconds must elapse before the test will initiate. Upon engagement of SAS 1, all rate gyroscope automatically set to predetermined rates and checked for magnitude and polarity of response. Simultaneously, the SAS 1 response rate gyro inputs is compared against a digital model, Failures displayed on the fail status panel and stored in the BIT code display on the AFCC. The automatic preflight takes approximately 10 seconds to complete.
84
What are the indications and aircraft response if the RAD ALT fails while in APPR mode?
Indications: Master caution, RADALT FAIL and AFCS DEGRADED cautions, CPLR and ALT fail advisories, LAWS tone. Radar altimeter declutters and red Xs will appear in digital readout.
Aircraft response: APPR disengages. BAR ALT hold engages at failure altitude. >50 KIAS - Airspeed hold engages. <50 KIAS - Attitude hold engages. DEPART Function not available.
85
What are the indications and aircraft response if the RAD ALT fails while in HVR mode?
Indications: Master caution, RADALT FAIL and AFCS DEGRADED cautions, CPLR and ALT fail advisories, LAWS tone. Radar altimeter declutters and red Xs will appear in digital readout.
Aircraft response: HVR remains engaged, BAR ALT engages at failure altitude, HVR must be manually deselected on AFCS control panel, DEPART function not available.
86
What are the indications and aircraft response if the RAD ALT fails while in DEPART mode?
Indications: Master caution, RADALT FAIL and AFCS DEGRADED cautions, CPLR and ALT fail advisories, LAWS tone. Radar altimeter declutters and red Xs will appear in digital readout.
Aircraft response: APPR
87
What are the indications and aircraft response if the RAD ALT fails while in APPR mode?
Indications: Master caution, AFCS DEGRADED caution, EGI 1/2 I/O advisory, ATT, CPLR, CORD, AUG, A/S, and HDG fail advisories.
Aircraft response: APPR/HVR/DEPART disengages. RADALT hold remains engaged, but is degraded. All other autopilot functions lost. Aircraft may develop a slow pitch, roll, and/or yaw rate.
88
Describe the automatic departure profile.
Climb rate: 240 fpm.
Acceleration: <85 KIAS - 3 KTS/sec, above 100 KIAS - 1KT/sec
89
What does the CPLR fail advisory light mean?
Approach/hover coupler capability has been lost. ATT, A/S, Or ALT light may also be illuminated.
90
What does the CORD fail advisory light mean?
Turn coordination is lost if AUG, or SAS 1 and SAS 2, or A/S light is illuminated.
91
What does the CH fail advisory light mean?
Loss of crew hover.
92
What does the AUG fail advisory light mean?
Loss of hover augmentation. A/S, ATT, or SAS 1 and SAS 2 lights may also illuminate.
93
What does the ATT fail advisory light mean?
Pitch or roll attitude hold has been lost. If TRIM light is also illuminated, both pitch and roll attitude hold have been lost or are malfunctioning. If pitch attitude failure occurs, the A/S light will also illuminate, indicating airspeed hold is not available. May also indicate a 3 degree miscompare between EGIs.
94
What does the A/S fail advisory light mean?
Loss of airspeed hold. The autopilot may continue to hold pitch attitude unless pitch attitude failure also occurs, indicated by the ATT light.
95
What does the HDG fail advisory light mean?
Heading hold has been lost, the ability to synchronize heading hold has been lost, or collective-to-yaw electrical mixing has been lost.
96
What does the ALT fail advisory light mean?
If barometric altitude hold was engaged, altitude hold is lost. If radar altitude hold is desired, cit must be selected. If radar altitude hold was engaged, barometric altitude hold will automatically engage unless the failure prevents altitude hold operation.
97
What does the SAS 1 fail advisory light mean?
A malfunction had occurred, causing improper pitch, roll, or yaw SAS 1 operation. SAS 1 should be disengaged to ensure proper SAS 2 operation in the affected channel.
98
What does the SAS 2 fail advisory light mean?
A malfunction has occurred, causing improper pitch, roll, yaw or collective SAS 2 operation. The affected axis will be automaticcally disengaged.
99
What does the BIAS fail advisory light mean?
There is no BIAS function, however the light will illuminate during the lamp test.
100
What does the TRIM fail advisory light mean?
Cyclic pitch or roll trim, yaw pedal trim, or collective trim is lost or malfunctioning.
101
What are the types of control mixing?
1. Collective to yaw.
2. Collective to lateral.
3. Collective to longitudinal.
4. Yaw to longitudinal.
5. Collective/airspeed to yaw.
102
Describe collective to yaw control mixing
Cause: Nose yaws right when collective is increased
Result: Tail rotor thrust is increased
103
Describe collective to lateral control mixing
Cause: Helicopter drifts right when collective is increased.
Result: Rotor disc is tilted left.
104
Describe collective to longitudinal control mixing
Cause: Nose pitches up and helicopter drifts aft when collective is increased.
Result: Rotor disc is tilted forward.
105
Describe yaw to longitudinal control mixing
Cause: Nose pitches down and helicopter drifts forward when left pedal is applied.
Result: Rotor disc is tilted aft.
106
Describe collective/airspeed to yaw control mixing
Cause: Camber of tail rotor pylon varies side load with airspeed. Nose yaws left as airspeed increases.
Result: A portion of the main rotor torque compensation is provided by a trim input that is proportional to collective position and airspeed. The trim input is then progressively washed out as pylon side loads increase with airspeed.
107
What's required for the Pylon FLIGHT light to be illuminated?
The pylon lockpin switch, 5° switch, tail rotor blade indexer switch, and two stabilator lockpin switches.
