Century 2000 User manual

CENTURY 2000
AUTOPILOT FLIGHT SYSTEM
PILOT’S OPERATING MANUAL
REVISED APRIL 9, 1999
68S1035

FACTORY SERVICE CENTERS
Century Flight Systems, Inc. has established Factory
owned and operated Customer Service Center. The
personnel operating this Center are dedicated to providing
Customer Satisfaction with our products.
Besides providing technical consultation, Service Center
personnel also provide competent repairs and spares
support to our dealers as well as direct customer in or out
of warranty repair service. The location of our Factory
Service Center is:
Municipal Airport, Mineral Wells, Texas
Product Support
Telephone: [phone]
If any time you need service at the Center please call for
and arrange for an appointment. This way, we can
minimize shop repair time.
LOG OF REVISIONS
06-01-87 Altitude Preselect Addition
Pages i, ii, Replaced
Pages 75, 76, 77, 78 Added
06-01-87 Page 9, 10 Replaced
07-19-94 Preflight Test Sequence
Page 7a, 7b, 7c, and 7d added.
02-07-97 Directional Gyro Section added.
Book reformatted and pages renumbered.
12-19-97 Add to NOTE on pages 7, 9, and 11.
04-09-99 Changes to Yaw Damper write-up on
page 22.
i ii

FORWARD . . . . . 1
FEATURES . . . . . 3
. .
Autopilot ON-OFF . . . . .
Master Disconnect/Trim Interrupt . . 6
. . 7
Preflight Test Sequence (“A” Mod. . .
Preflight Test Sequence (“A” Mod. Trim Prompt 11
13
Lateral Operating Modes . . . 13
. . . . . .
Heading Systems . . . . .
Selected Intercept Angle . . . 16
Approach . . . . . 17
. . . . 18
Review of Interlocks and Failure Warnings 21
Yaw Damper Systems . . . .
DIRECTIONAL GYRO . . . . 23
. . . . . . 25
C2000 FLIGHT DIRECTOR/STEERING HORIZON 27
CENTURY 2000 OPERATING TECHNIQUES 29
HSI VOR NAVIGATION . . . .
HSI VOR APPROACH . . . . 32
. . . .
HSI GS ARMING & CAPTURE . . .
HSI LOCALIZER BACK COURSE . . .
DG VOR NAVIGATION . . . . 55
. . . . 57
DG LOCALIZER APPROACH - - - 63
- - - 70
. . . . . 73
. . . .
WARRANTY . . . . . 75
iii

FORWARD
The Century Flight Systems, Inc. Century 2000 Autopilot is an advanced
General Aviation Flight Control System utilizing “State of the Art”
electronic techniques.
In this handbook we have detailed the features, functions and general
operating instructions of the Century 2000 System.
May we suggest that you do two things:
1. Read this handbook and your Airplane Flight Manual
Supplement. The handbook presents general operating
procedures. Each aircraft installation has an Airplane Flight
Manual Supplement or Autopilot Handbook that contains FAA
approved flight procedures and operating limitations in that
particular model aircraft. The appropriate AFM Supplement is a
document which must be aboard U.S. Registered Aircraft with the
autopilot installed.
2. Spend some VFR time with the equipment to become familiar
with its operation so that you may have the full benefit of its
capabilities.
NOTE
The Century 2000 Autopilot is a modular design. It may be installed and
operated as a roll axis only autopilot, roll and pitch axis, or a roll, pitch,
and yaw axis. The asterisk symbol (*) appearing before certain sections
of this manual indicates instructions for those systems having the pitch
expansion installed. Operators of the roll only Century 2000 should
disregard the sections, paragraphs and sentences marked by asterisk.
THE CENTURY 2000 3-AXIS IFCS
12

FEATURES
The Century 2000 Autopilot
This autopilot only version uses a standard artificial horizon in
combination with a directional gyro (DG) or an NSD-360A, NSD-1000
Horizontal Situation Indicator (HSI). A Century Flight Systems, Inc. Yaw
Damper (Y/D) may be incorporated with the Century 2000 when a Y/D is
certified for your plane.
An outstanding feature of the Century 2000 is that it has a rate based
inner loop for short term dynamics. This means that rate information is
derived from the horizon so that motion about the roll and pitch axis is
programmed to occur at a rate appropriate to the activity. Examples of
controlled rate motion are as follows:
ROLL AXIS:
Heading Command - Roll at 5°° per second diminishing near bank
limit.
Navigation Soft Mode - Roll at 2.5 degrees per second to reduced
bank limit (8°°).
Gust Disturbances - Resisted by certificated servo velocity.
*PITCH AXIS:
Command Attitude - 0.7°° per second attitude change.
Gust Recovery - Maximum rate consistent with passenger comfort.
Maximum System Capability - 2.4°° per second .
CENTURY OPERATING CONTROLS
The MODE PROGRAMMER push-button switches are backlighted and
dimming is provided by the control panel light dimmer switch.
The MODE ANNUNCIATOR light intensity is controlled automatically by a
self-contained ambient light level sensor; this feature provides optimum
Mode Annunciator light level for all cockpit conditions. The Century 2000
Autopilot is activated with the Aircraft Master switch and operates in a
low power state until the autopilot operation is desired. Mode selection is
made by pushing the desired mode switch on the Mode Programmer. The
selected mode will be illuminated on the Mode Annunciator.
*A separate Trim Master switch is located on the Control Panel. Autotrim
function is activated by the Autopilot Engage switch.
34

AUTOPILOT ON-OFF -
Autopilot engage is accomplished by pressing
the momentary ON switch on the left side of the
Programmer. The Autopilot will engage in the
HDG mode. If the system is pitch expanded, the
ATT mode will also be present when engaged
and the autopilot will synchronize to the
existing aircraft pitch attitude.
In HDG mode the aircraft will track the heading selected on the DG or HSI.
In NAV, APR, or REV modes the aircraft will intercept and track any
properly programmed radio-defined course. Instructions for proper radio
setup in these modes are included in this manual.
* In ATT mode the autopilot will synchronize to the aircraft pitch attitude
upon engagement.
* In ALT mode the aircraft will synchronize to the indicated altitude
present at the time of engagement.
The autopilot may be disengaged by pressing
the momentary OFF switch on the programmer,
* by pressing the AP OFF switch on the control
wheel trim switch; * by pressing the Master
Disconnect/Trim Interrupt switch, if present on
the control wheel; or by interrupting power at
the Aircraft Master switch. Disengagement
causes the AP annunciator to flash for 5
seconds.
*MANUAL ELECTRIC TRIM - With the Aircraft and Trim Master switches
on, a manually operated electric trim function is activated by the control
wheel trim switch. This switch serves a dual function:
*1. Disengage the Autopilot.
2. Activate manual electric trim.
*Moving the red portion of the trim switch forward or aft will cause
autopilot disengagement. Moving both parts of the trim switch forward or
aft simultaneously will disengage the autopilot and cause the trim to run
up or down.
*MASTER DISCONNECT/TRIM INTERRUPT
Many Century 2000 autopilots incorporate an additional switch on the
control wheel (usually a red button). Pressing this button will disconnect
the Century 2000, the Yaw Damper (if installed), and will interrupt the
operation of the Trim System. Release of the button will restore power to
the Trim System. However, the Autopilot will return to the HDG and ATT
mode and will require re-engagement in order to resume automatic flight.
*AUTOTRIM - The Century 2000 autopilot is equipped with automatic pitch
trim. When the Trim Master switch is on, Autotrim is activated by
engaging the autopilot.
*The Autotrim system is fail safe in design. The integrity of the trim
system is verified by the preflight test.
ON
OFF
WHEEL SWITCH CONFIGURATIONS
VARY WITH AIRCRAFT MODEL.
6
5

PREFLIGHT TEST SEQUENCE
CENTURY 2000 PREFLIGHT PROCEDURES
FOR NO MOD. CENTURY 2000
NOTE
During system functional check the system must be provided adequate
D.C. voltage (12.0 VDC or 24 VDC min.) and instrument air (4.2 in. Hg.
Min.). It is recommended that the engine be operated to provide the
necessary power and that the aircraft be positioned in a level attitude,
during the functional check. Due to the weight of the elevator in certain
models of aircraft, steps 4 and 5 may not move the control wheel. To
verify correct direction of commands, support elevators to remove weight
and continue steps.
AUTOPILOT/AUTOTRIM - To be performed before the first flight of each
day.
*1. Trim Master switch - ON.
2. Engage autopilot.
3. Move the heading bug left and right of the lubber line. Observe that
the control wheel moves in the direction of the heading bug
displacement.
*4. Press the DN switch - verify that the control wheel moves in the down
direction. Verify that after approximately a 3 second delay, the trim
moves in the down direction.
*5. Press the UP switch - verify that the control wheel moves in the up
direction. Verify that after approximately a 3 second delay, the trim
moves in the up direction.
6. Grasp control wheel and override roll and *pitch servo actuators to
assure override capability.
7. Hold control yoke and disengage autopilot by activating the AP OFF
switch on the control wheel or by the programmer off switch.
8. Check controls through full travel in roll and pitch to assure complete
autopilot disengagement.
9. With autopilot OFF, press TST switch. All annunciators shall
illuminate.
*10.After “GS” and “ALT” annunciators extinguish release TST SWITCH;
only “HDG”, “ATT”, and “TST” remain illuminated.
*11.Press DN switch, HDG, and ATT annunciators remain illuminated, TST
may momentarily flicker and then remains illuminated.
*12.Press UP switch, HDG, and ATT annunciators remain illuminated, TST
may momentarily flicker and then remains illuminated.
*13. Momentarily press TST switch. HDG and ATT annunciators remain
illuminated, TST annunciator flashes.
*14. Press and hold DN switch. TST annunciator extinguishes
*15.Press and hold the UP switch. TST annunciator extinguishes.
*16.Momentarily press and release TST switch. HDG and ATT
annunciators remain illuminated, TST annunciator extinguishes.
*COMMAND TRIM SYSTEM - To be performed before the first
flight of each day.
1. Using the control wheel trim switch, verify normal trim up and down
operation.
2. Move red portion of trim switch forward and aft. Observe that the trim
system does not operate.
3. Release the red bar on the control wheel trim switch. Move the black
portion fore and aft. Observe that the trim system does not operate.
This completes the test sequences.
CAUTION
Any failure of the above procedures indicates that a failure exists in the
system and the system shall not be operated until the failure has been
located and corrected.
CAUTION
Check the elevator trim setting before takeoff.
7 8

PREFLIGHT TEST SEQUENCE
CENTURY 2000 PREFLIGHT PROCEDURES
FOR “A” MOD. CENTURY 2000
NOTE
During system functional check the system must be provided adequate
D.C. voltage (12.0 VDC or 24 VDC min.) and instrument air (4.2 in. Hg.
Min.). It is recommended that the engine be operated to provide the
necessary power and that the aircraft be positioned in a level attitude,
during the functional check. Due to the weight of the elevator in certain
models of aircraft, steps 4 and 5 may not move the control wheel. To
verify correct direction of commands, support elevators to remove weight
and continue steps.
AUTOPILOT/AUTOTRIM - To be performed before the first flight of each
day.
*1. Trim Master Switch - ON.
2. Engage Autopilot.
3. Move the heading bug left and right of the lubber line. Observe that
the control wheel moves in the direction of the heading bug
displacement.
*4. Press the DN Switch - verify that the control wheel moves in the down
direction. Verify that after approximately a 3 second delay, the trim
moves in the down direction.
*5. Press the UP Switch - verify that the control wheel moves in the up
direction. Verify that after approximately a 3 second delay, the trim
moves in the up direction.
6. Grasp control wheel and override roll and pitch servo actuators to
assure override capability.
7. Hold control yoke and disengage autopilot by activating the AP OFF
Switch on the control wheel or by the programmer off switch.
8. Check controls through full travel in roll and pitch to assure complete
autopilot disengagement.
9. With autopilot OFF, press and hold TST switch. All available mode
annunciators shall illuminate for 3 seconds then extinguish and the
AP shall flash as long as the TST switch is held.
*10. Release the TST switch. Only HDG, ATT and TST shall be illuminated.
*11.Press and hold the DN switch. The TST annunciator may momentarily
flicker but should remain illuminated. HDG and ATT shall
remain on. Release the DN switch.
*12.Press and hold the UP switch. The TST annunciator may momentarily
flicker but should remain illuminated. HDG and ATT shall remain on.
Release the UP switch.
*13.Momentarily press and hold the TST switch. The AP and TST
annunciators shall flash and the HDG and ATT shall stay illuminated.
Release the TST switch. The HDG and ATT shall remain on the TST
annunciator shall remain flashing.
*14.Press and hold the DN switch. The TST annunciator shall extinguish.
HDG and ATT shall remain on. Release the DN switch.
*COMMAND TRIM SYSTEM - To be performed before the first flight of
each day.
1. Using the control wheel trim switch, verify normal trim up and down
operation.
2. Move red portion of trim switch forward and aft. Observe that the trim
system does not operate.
3. Release the red bar on the control wheel trim switch. Move the black
portion fore and aft. Observe that the trim system does not operate.
CAUTION
Any failure of the above procedures indicates that a failure exists in the
system and the system shall not be operated until the failure has been
located and corrected.
CAUTION
Check the elevator trim setting before takeoff.
9 10

PREFLIGHT TEST SEQUENCE
CENTURY 2000 PREFLIGHT PROCEDURES
FOR “A” MOD. CENTURY 2000
TWO AXIS TRIM PROMPTER
NOTE
During system functional check the system must be provided adequate
D.C. voltage (12.0 VDC or 24 VDC min.) and instrument air (4.2 in. Hg.
Min.). It is recommended that the engine be operated to provide the
necessary power and that the aircraft be positioned in a level attitude,
during the functional check. Due to the weight of the elevator in certain
models of aircraft, steps 4 and 5 may not move the control wheel. To
verify correct direction of commands, support elevators to remove weight
and continue steps.
1. Engage autopilot.
2. Move the heading bug left and right of the lubber line. Observe that
the control wheel moves in the direction of the heading bug
displacement.
3. Press the DN Switch - Verify the control wheel moves in the
DOWN direction.
** Verify that after approximately a 3 second delay, the Trim DN
Prompt flashes.
4. Press the UP Switch - Verify the control wheel moves in the
UP direction.
** Verify that after approximately a 3 second delay the Trim UP Prompt
flashes.
5. Grasp the control wheel and override roll and pitch servo’s to assure
override capability.
6. Hold control wheel and disengage autopilot. Check controls through
full travel in all axis to assure complete autopilot disengagement.
7. With autopilot OFF, press and hold TST switch. All available mode
annunciators shall illuminate for 3 seconds then extinguish and the
AP shall flash as long as the TST switch is held.
8. Release the TST switch. Only HDG, ATT and TST shall be illuminated.
9. Press and hold the DN switch. The TST annunciator may momentarily
flicker but should remain illuminated. HDG and ATT shall remain on.
Release the DN switch.
10. Press and hold the UP switch. The TST annunciator may momentarily
flicker but should remain illuminated. HDG and ATT
shall remain on. Release the UP switch.
11. Momentarily press and hold the TST switch. The AP and TST
annunciators shall flash and the HDG and ATT shall stay illuminated.
Release the TST switch. The HDG and ATT shall remain on the TST
annunciator shall remain flashing.
12. Press and hold the DN switch. The TST annunciator shall extinguish.
HDG and ATT shall remain on. Release the DN switch.
13. Press and hold the UP switch. The TST annunciator shall extinguish.
HDG and ATT shall remain on. Release the UP switch.
14. Momentarily press the TST switch. HDG and ATT shall remain
illuminated, TST annunciator shall extinguish.
**The control wheel may have to be assisted to move up and/or down.
CAUTION
Any failure of the above procedures indicates that a failure exists in the
system and the system shall not be operated until the failure has been
located and corrected.
CAUTION
Check the elevator trim setting before takeoff.
11 12

PREFLIGHT TEST SEQUENCE
CENTURY 2000 PREFLIGHT PROCEDURES FOR
“A” MOD. CENTURY 2000 SINGLE AXIS
NOTE
During system functional check the system must be provided adequate D.C.
voltage (12.0 VDC or 24 VDC min.) and instrument air (4.2 in. Hg. Min.). It is
recommended that the engine be operated to provide the necessary power and
that the aircraft be positioned in a level attitude, during the functional check.
1. Engage autopilot.
2. Move the heading bug left and right of the lubberline. Observe that the
control wheel moves in the direction of the heading bug displacement.
3. Grasp the control wheel and override roll servo to assure override
capability.
4. Hold control wheel and disengage autopilot. Check control through full
travel to assure complete autopilot disengagement.
5. With autopilot OFF, press and hold TST switch. All available mode
annunciators shall illuminate.
CAUTION
Any failure of the above procedures indicates that a failure exists in the
system and the system shall not be operated until the failure has been
located and corrected.
CAUTION
Check the elevator trim setting before takeoff.
LATERAL OPERATING MODES
HEADING - In HDG mode the autopilot will
capture and hold the heading selected on the
DG or HSI. HDG annunciator will illuminate.
NAVIGATION - In NAV mode the autopilot has an
automatic 45 degree VOR-LOC intercept angle.
Selected angle intercepts are available when the
system is equipped with NSD-360A, NSD-1000 or
other HSI.
When executing an intercept, the rate at which the aircraft is closing upon
the selected radio-defined course is determined by the computer and at
the proper time an on-course turn is initiated. thirty-five seconds after the
on-course turn the computer will reduce its bank limits to 13 degrees.
After 70 seconds the bank limits will be reduced to 8 degrees to produce a
‘soft’ navigation mode when tracking a VOR signal. The system will
remain in ‘soft’ mode during station passage. However, if a new course
which requires re-intercept is selected, the ‘soft’ mode will unlock and the
intercept sequence will reoccur.
NOTES
The NAV mode should be used when executing a holding pattern on the
localizer to prevent automatic glideslope coupling.
When radio receiver is tuned to a localizer frequency, the coupler will
operate with localizer (APR) dynamics in the NAV mode.
HDG
NAV
ON HDG NAV APR REV DN
OFF TST FD YD ALT UP
AP
NAV
ON HDG NAV APR REV DN
OFF TST FD YD ALT UP
HDGAP
13 14

HEADING SYSTEMS
In systems equipped with a DG the autopilot heading bug must be set to
match the selected VOR/LOC course when in NAV, APR, or REV modes.
For loran or GPS tracking, set the heading bug to the “desired bearing”
information.
In systems equipped with and NSD-360A, NSD-1000 or other HSI
instrument, the heading bug is disabled when in the NAV, APR, or REV
modes. In these modes the azimuth information to the autopilot is
provided by the radio course pointer.
NOTES
In systems equipped with an NSD-360A, NSD-1000 or other HSI always set
the radio course pointer to the Front Course Inbound Heading when
operating in the APR or REV modes.
In systems equipped with a DG, during an instrument approach, the
heading bug must be set to match course for the segment of the
approach being flown when using the NAV, APR, or REV modes.
See section on operating techniques for additional operating instructions
for the NSD-360A, NSD-1000 and the DG.
SELECTED INTERCEPT ANGLE
In systems equipped with a NSD-360A, NSD-
1000 or other HSI, a selected intercept angle
function is available while operating in the NAV,
APR, and REV modes.
Selected angle intercepts are initiated by
performing the following steps:
1. While operating in the HDG mode, set the
course pointer to the desired radial .
2. Set the heading bug on the NSD to the
desired intercept heading.
3. Press the HDG and NAV, HDG and APR or
HDG and REV mode buttons simultaneously.
Both HDG and the selected lateral mode will now illuminate on the
annunciator. As the aircraft begins its on-course turn, the HDG
annunciator will extinguish indicating that the system has captured the
selected radio course and is now receiving azimuth input from the radio
course pointer.
NOTE
If valid radio signal is lost after initiating a selected angle intercept, the
applicable navigation mode annunciator will flash and the autopilot will
remain in the HDG mode.
HDG NAV
HDG APR
HDG REV
ON HDG NAV APR REV DN
OFF TST FD YD ALT UP
HDGAP
NAV
15 16

APPROACH - The APR mode provides an
automatic 45 degree VOR-LOC intercept angle
and selected angle intercepts when the system
is equipped with an NSD-360A, NSD-1000 or
other HSI.
The intercept, crosswind, and tracking sequences are similar to those
described in the NAV mode of operation except that 70 seconds after the
on-course turn the bank angles are reduced to 12 degrees. *The APR
mode has additional enabling logic for the automatic glideslope arm,
capture, and track sequence and must be used on ILS approaches.
REVERSE (Back Course) - The REV mode is for
use in tracking the localizer back course
Inbound and front course Outbound or VOR
course Outbound.
Automatic 45 degree intercepts, selected angle intercepts, crosswind
correction and tracking are as described in the APR mode except that
response to radio signals is reversed.
NOTES
When using an NSD-360A, NSD-1000 or other HSI always set the radio
course pointer to the inbound front course localizer heading.
When using a DG, always set the heading bug to the final approach
heading to the airport.
*PITCH OPERATING MODES
*ALTITUDE - ALT mode will cause the aircraft to
maintain the pressure altitude present at the
time of ALT engagement.
*ALT may be engaged at maximum rate of climb or descent, but for
passenger comfort, rate of climb or descent should be reduced to 1,000
feet per minute or less prior to ALT engagement. Depressing either the
pitch UP or DN switch will shift the AP mode back to ATT mode.
*ATTITUDE - ATT mode places pitch command with the pitch UP and DN
switches. Pitch is always synchronized to the existing aircraft attitude
after pitch modification. When engaging the autopilot or when
transferring the system to ATT from ALT, the aircraft will maintain its
existing attitude.
*PITCH MODIFIER SWITCHES - The pitch
modifier switches are momentary push-button
type, located on the right side of the Mode
Programmer, used to modify the airplane’s
attitude and to shift the AP from the ALT mode
to the ATT mode.
*GLIDESLOPE COUPLING - In the presence of selected APR mode only
and other enabling logic, the glideslope function is fully automatic.
Therefore, no GS engage switch is used.
APR
ALT
REV
DN
UP
17 18

*GS mode may be entered from either ATT or ALT mode, from either
above or below the glideslope.
*Capture of the glideslope depends upon satisfying conditions which will
complete the arming sequence. After arming, capture will occur just
before glideslope interception so as to rotate smoothly to interception.
This “anticipative capture” point is determined by the rate of closure
satisfying a computer equation. In order for the GS mode to arm, the
following conditions must exist simultaneously:
1. No. 1 NAV radio channeled to localizer frequency.
2. Localizer deviation must be less than 90 percent either side of center.
3. A valid localizer signal (no flag).
4. A valid glideslope signal (no flag).
5. APR mode selected.
*When these conditions are met the GS annunciator will illuminate in
conjunction with the active pitch mode annunciator indicating glideslope
is armed.
*When “anticipative capturing” occurs, the active pitch mode annunciator
will extinguish leaving only the illuminated GS annunciator to indicate
that transition to the glideslope signal has occurred.
*The GS mode may be deactivated by selection of any other pitch mode
(ALT, ATT) but automatic recapture of the glideslope may occur in ALT or
ATT modes.
NOTES
The NAV mode should be used when executing a holding pattern ton the
localizer to prevent automatic glideslope coupling.
When radio receiver is tuned to a localizer frequency, the coupler will
operate with localizer (APR) dynamics in the NAV mode.
*CWS MODE (Pitch Sync) - The system is
equipped with a control wheel steering switch
located on the horn of the pilot’s control wheel.
When depressed, this switch will disengage the
roll and pitch servos to allow manual
maneuvering.
*When released the system will re-engage in the
lateral (roll) mode previously in use.
*If the autopilot is in ALT mode the system will synchronize to the
indicated altitude present upon release of the CWS switch.
*If the Autopilot is in the ATT mode the system will synchronize to the
pitch attitude present at the time of release.
CENTURY 2000 WITH TRIM PROMPTING
The Century 2000 may be ordered as a Trim
Prompting autopilot. This means automatic
control (autotrim) of the elevator trim is not
available on these system. When the autopilot
displays a flashing TRIM UP or TRIM DOWN on
the annunciator, the pilot should manually move
the trim control of his aircraft in the direction
indicated on the autopilot. When the autopilot
determines that the trim condition is satisfied,
the trim lamp on the annunciator will extinguish
and the pilot should stop his trim
action. There are 2 degrees of trim prompting. For a small trim error the
trim prompt will flash approximately once each second. A large trim error
will cause the prompt to flash approximately 3 times per second. A large
error not corrected for a period of approximately 2 minutes will sound an
alert for 5 seconds. The alert will repeat every 2 minutes until the large
error is corrected.
TRIM
DN
TRIM
UP
19 20

REVIEW OF INTERLOCKS AND FAILURE WARNINGS
The Century 2000 Systems include a number of automatic interlocks that
will prevent system operation or individual mode operation if the input
information is not valid or if other pre-requisite conditions do not exist.
In addition to the interlocks, the system will annunciate various failure
conditions as advisory information for the pilot. Following is a brief
description of the interlocks and warnings provided.
INTERLOCKS
Autopilot engagement is inhibited unless valid gyro excitation is being
provided by the system.
*Selection of ALT mode is inhibited if the system altitude information in
unreliable or if the entire system has not been powered for a time
sufficient to allow temperature stabilization, usually 2 to 6 minutes
depending on ambient temperature.
If the navigation information becomes invalid during selected angle
intercepts the appropriate NAV/APR/REV annunciator will flash and
automatic mode switching from HDG to the armed navigation mode will
be inhibited.
WARNINGS
LOW VOLTAGE - When the aircraft bus voltage provided the system falls
below the minimum required for reliable system function, any mode
annunciator not already illuminated will flash.
ATTITUDE GYRO EXCITATION - Absence of valid gyro excitation will
cause the autopilot to disengage the and the AP annunciator to flash.
The autopilot cannot be re-engaged until this condition is corrected.
AP DISENGAGEMENT - Anytime the autopilot is disengaged the AP
annunciator will flash and sound an alert for approximately 5 seconds,
then remain off.
NAVIGATION INFORMATION INVALID - The appropriate navigation mode
annunciator will flash when selected and invalid navigation signals are
present (NAV flag in view).
*GLIDESLOPE INFORMATION INVALID - The GS annunciator will flash
when glideslope information is invalid or any other GS Arming condition
is lost (GS flag in view) after glideslope capture. If valid glideslope
information or any other GS Arming condition is not available during the
arming sequence, the system will not arm and glideslope capture will not
occur.
YAW DAMPER SYSTEM
(YAW DAMPER EXPANDED SYSTEMS ONLY)
The Century Flight Systems, Inc. Yaw Damper
system is a frequently installed expansion to the
Century 2000. The system has only one control
- the YD Push Button. This expansion may be
operated without the autopilot engaged.
For pilot assistance and passenger comfort, its function is to add
additional stability to the yaw axis of the aircraft and minimize any
tendency to hunt or Dutch roll in the aircraft. In addition, the Yaw Damper
incorporates an “electronic slip/skid sensor” to assist in coordinating
turns and trimming the aircraft under conditions of asymmetric power.
The Yaw Damper does not ordinarily compensate for rudder trim
variations with speed changes and therefore may “bump” the rudder
controls slightly when engaged.
The Yaw Damper is automatically engaged when the Century 2000
autopilot is engaged. The Yaw Damper may also be engaged through the
YD switch on the Century 2000 if autopilot engagement is not desired. A
YD light on the annunciator of the Century 2000 confirms the Yaw Damper
is engaged. The Yaw Damper may be disengaged by pressing the YD
switch on the Century 2000 or by pressing the Master Disconnect or the
Master Disconnect/Trim Interrupt switch (if system has autotrim) located
on the control wheel. The YD annunciator light will extinguish to indicate
disengagement.
On some models of aircraft, the Yaw Damper cannot be incorporated into
the Century 2000 Autopilot. On those models the Yaw Damper is
considered as stand alone. To engage the Yaw Damper the pilot will have
to press the remote mounted panel switch. This switch is an
electromechanical switch which will illuminate to confirm Yaw Damper
engagement. To disengage, the switch must be pressed again.
YD
21 22

Directional Gyro
The Heading Selector DG replaces the standard directional gyro and
provides a fully visible heading indicator around the normal DG opening.
The DG dial is marked in 5 degree intervals and numbered each 30
degrees around its azimuth. A center index is provided at the top to align
selected headings. Additional indices are located each 45 degrees to
facilitate rapid turn selection without mental arithmetic. Any heading may
be selected, either before or after engagement, and turns up to 180
degrees may be programmed directly, either right or left. If the heading
indicator is rotated beyond 180 degrees from the DG card heading, the
heading selector will command a reversal in bank to reach the resultant
selected heading in the shortest direction .
The DG card is normally set to the magnetic compass with the card set
knob on the left in the usual fashion, while the heading selector indicator
is rotated by the heading selector knob on the right. It will still be
necessary for the pilot to verify the compass card heading with the
magnetic compass periodically. Direction of rotation of both the knobs
and indicator commands the same direction of turn.
NSD-360A, NSD-1000 AND
OTHER HEADING SYSTEMS
The Century 2000 autopilot may be optionally equipped with the Century
Flight Systems, Inc. NSD-360A or NSD-1000 HSI. The explanation which
follows will be based on Century’s HSI, however the principles will apply
equally to the heading systems of other manufacturers provided the
differences in design, features and concepts are ascertained and allowed
for such as slaving, knob location, size, etc.
The NSD-360A and the NSD-1000 (Navigation Situation Display) are
basically identical units except for the gyro capsule. The 360A is an air
driven gyro where as the 1000 is an electric gyro. The HSIs have
electrically servoed heading card driven by the information processed
from the gyro capsule. Warning flags and indicators include NAV flag,
glideslope flag, TO/FROM meter and heading flag. Lateral radio
information is presented by the left/right meter and vertical radio
information is presented by the glideslope meter. Autopilot heading
information is represented by positioning the heading bug to the desired
heading track.
23 24
Lubber Line
Autopilot
Heading Bug
Miniature
Airplane
Heading
Selector
Knob (Push)
Card Set
Knob (Push)
Compass
Card

DC
NSD-1000
Autopilot course information is derived from course needle position
(direction) and left/right radio information (deviation from desired radio
track) to provide precise intercept and track capability.
NOTE
The Century 2000 is capable of using radio information provided by a
loran or GPS. There are several important factors to consider when using
those units with the autopilot and HSI.
Because the HSI incorporates an integrated course/left-right display and
an OBS resolver, a switching device will be required in order for the HSI
to display the selected information.
Most manufacturers of loran and GPS have the capability to adjust the
course width (CDI sensitivity) of their units. Course width is measured in
nautical miles from full scale left to full scale right deflection of the CDI. If
the course width is too wide, the autopilot will be insensitive to the
movement of the CDI. If the course width is too narrow, the autopilot will
be overly responsive to the CDI movement.
For proper autopilot operation with a loran or GPS, the autopilot needs
both direction and deviation. Directional information is provided by the
heading bug, if a DG is being used, or by the course needle, when an HSI
is being used. When a waypoint is called up, the loran or GPS will
display a “desired track”. The heading bug or course arrow must match
this “desired track”. If you use multiple legs in a flight, you must match
the heading bug or course arrow with the new “desired track”.
25 26
Left/Right
Radio
Deviation
Meter
Course Selector
Knob
Glideslope
Flag
Heading Flag
Course
Needle
Heading Selector
Knob/Card Set
(push)
Slaving
Meter
Lubber Line
Autopilot Heading
Bug
Glideslope
Pointer
NAV Flag

FLY LEFT FLY RIGHT
FLY UP FLY DOWN
CENTURY 2000 FLIGHT DIRECTOR
STEERING HORIZON SINGLE QUE
With the addition of the Flight Director expansion, the pilot may choose to
program a particular flight sequence and monitor autopilot maneuvering
by observing the steering bar or he may switch the autopilot off and place
himself in the control system loop by following commands of the steering
bar. Pressing the FD switch on the computer programmer will activate
the flight director steering bars and the annunciator will illuminate FD.
The great advantage of the Flight Director is that the computer observes
many inputs, compares these inputs to the sequence programmed by the
pilot and resolves differences into combinations of four commands: Fly
Up, Fly Down, Fly Left and Fly Right. To accomplish the programmed
maneuver, the pilot need only to “fly the delta into the ‘vee’ of the
steering bar”.
The Flight Director may be switched off and the steering bars stowed out
of view by momentarily pressing the FD switch on the programmer.
While the FD is on, the autopilot will stay in the mode of operation if the
autopilot is disengaged or when it is re-engaged. When the FD is off and
the autopilot is disengaged, the autopilot will revert to the default modes
of operation which is the HDG and ATT modes.
NOTE
The pilot should always keep in mind that the Steering Horizon displays
COMPUTED DATA and will give a command satisfied indication if the
pitch attitude and heading are satisfactory for normal conditions. The
system cannot compensate for inadequate power or airspeed to
accomplish the desired maneuver, therefore, a raw data display is
mandatory with the Flight Director display so that the pilot is constantly
presented with concise data on his heading and actual position on the
Localizer, Glideslope and VOR radial. For this reason, whenever the
Flight Director expansion is added, it is recommended that an HSI be
installed also .
FD
27 28

CENTURY 2000
OPERATING TECHNIQUES
In the pages that follow, we have included techniques for:
VOR Navigation
VOR Approaches
Localizer Approaches
Glideslope Arming & Coupling
Localizer Back Course
Note: The Century 2000 autopilot is capable of tracking lateral information
from a loran or GPS. Several factors in procedure and operation are important
to remember. Adjust the course width (CDI sensitivity) of the loran or GPS to
insure it is not too wide or too narrow (represented as nautical miles per dot). A
course width too wide would cause the autopilot to S-turn back and forth along
the desired track. Too narrow would cause the autopilot to be overly sensitive
to CDI movement. When tracking a desired waypoint, the bearing information
will be displayed on the loran or GPS. This bearing information must be
inputted into the autopilot through either the heading bug (when using a DG) or
the course arrow (when using an HSI) in order for the autopilot to track properly.
The photographs depict the Century Flight Systems Navigational Situation
Display 1000 (NSD 1000) as the HSI and the standard Directional Gyro. The
techniques are equally applicable to other compass systems.
VOR Navigation
29 30

VOR Navigation
STEP HSI MODE REMARKS
1HDG/NAV
ALT A selected angle intercept of
up to 90°may be selected by
setting the course arrow to the
desired radial and the heading
bug to the appropriate heading
for the desired intercept.
Press the HDG and NAV
switches on the autopilot. The
system will remain in this mode
until the on course turn.
2NAV
ALT After intercept, the system will
correct for crosswind and
adjust its internal radio
authority and limit bank angles
3NAV
ALT If a course change is required
at the VOR, reposition the
course arrow. If deviations
because of station passage is
not desired, press HDG and
set the heading bug on the
desired course.
4NAV
ALT Station switching is
accomplished by tuning the
nav receiver to the desired
station and setting the course
with the course arrow. A
course change of 45°or more
will cause the system to kick
out of “soft track” and set up a
45°intercept to the new
course.
VOR APPROACH
31 32

VOR Approach
STEP HSI MODE REMARKS
1NAV
ALT or
ATT
The VOR approach usually
begins from an enroute
situation.
2HDG
ALT or
ATT
As the VOR is neared, match
the heading bug to the course
flown and press the HDG
switch. Set the course arrow
for the inbound intermediate
course segment.
3REV
ALT or
ATT
As the VOR is crossed, press
the REV switch to fly the
selected course outbound.
Should a lower altitude be
required, press the MODIFIER
switch to make the altitude
change.
4REV
ALT or
ATT
When the desired altitude is
reached, press the ALT
switch.
VOR APPROACH
33 34