Midcontinent FLEXM D23-342 User manual

User Guide
For
MD23-342
Digital
Attitude Indicator
powered by
Rev
Date
Detail
Approved
1
10/11/22
Initial release.
BAW
This manual provides information intended for use by persons who, in accordance with current
regulatory requirements, are qualified to install this equipment. It is a supplement to the MD23
Installation Manual and Operating Instructions, p/n 9019161.
If further information is required, please contact Mid-Continent Instruments and Avionics.
Mid-Continent Instruments and Avionics Mid-Continent Instrument Co., Inc.
dba Mid-Continent Instruments and Avionics
User Guide UG342 9400 E. 34th Street N.
Revision 1 Wichita, KS 67226 USA
ph [phone]
www mcico.com

MD23-342
User Guide
Mid-Continent Instruments and Avionics 2 User Guide UG342, Revision 1
October 11, 2022
1.1 INTRODUCTION
The model MD23-342 digital attitude Indicator is a standard 2-inch (2-¼”) panel-mounted
instrument that displays aircraft attitude related functions. Based on Mid-Continent Instruments
and Avionics patented FLEXTM Custom Function Display, this FAA and EASA TSO-approved
instrument brings a highly capable and modern addition to the cockpit to display required
information and provide useful supplementary functions.
This User Guide is a supplement to the Installation Manual and Operating Instructions (IM),
MCIA part number 9019161. The IM contains all information associated with the standard
product, including installation procedures, product specifications, operating instructions,
certification data, and maintenance requirements. This User Guide provides additional
information associated with the specific features of the multifunction digital attitude Indicator. It
addresses product identification, electrical pinout, initial configuration setup, and in-flight user
operation.
1.2 PRODUCT IDENTIFICATION
Each MD23 is comprised of certified hardware and certified software. Within the context of the
certified software is a set of data items that can configure and customize the behavior of the unit.
This set of data is referred to as a Custom Instrument Definition, or a CID file. The CID file for
this instrument is pre-loaded and may be available for future updates via a standard USB flash
drive through the programming port on the rear of the unit.
A unique CID number has been assigned specifically to this application. The CID is identified by
its two-digit number and an alphabetic character representing the CID version, starting with “A”.
The identification of the hardware, software, and CID configurations are listed below. Both the
software version and the CID can be viewed on the Introduction Screen during the first few
seconds of applying power to the unit. This information can also be accessed on the Info page of
the Options Menu during Flight Mode.
1.3 PRODUCT FUNCTION
The Multifunction Digital Attitude Indicator provides an artificial horizon display of the aircraft pitch
and roll attitude. It also displays aircraft slip and turn rate and, optionally, heading (if connected to
an external source of heading data via ARINC labels 320 or 014).
The unit can be configured by the installer to account for panel tilt, roll offset, roll scale, aircraft
symbol and heading display options.
Unit Versions
Hardware Part Number
Software Version
CID
6420023-3 or -23
1.1.0, or later
42A, or later

MD23-342
User Guide
Mid-Continent Instruments and Avionics 3 User Guide UG342, Revision 1
October 11, 2022
2.1 CONNECTOR PINOUT
For standard pre-installation and installation instructions, including location, cable harness
assembly, pneumatic inputs (if applicable), mounting, and others, please refer to the IM.
Pinout identification specific to this CID is listed in the table below. A brief description is provided.
Further definition of the inputs and outputs should be documented in the technical requirements
and/or statement of work and are not provided within this User Guide.
Connector Pinout
Pin
Description
Function
1
Ground
Power return; connect to a/c ground
2
ARINC Out (A)
Labels 325, 324, and 320
3
ARINC Out (B)
(paired with pin 2)
4
Dimmer Input
5, 14, or 28VDC input (if used)
5
ARINC In (A)
Label 0320 or 014 (if used)
6
Reserved
7
Reserved
8
Reserved
9
Reserved
10
Reserved
11
Reserved
12
Reserved
13
Reserved
14
ARINC In (B)
(paired with pin 5)
15
Reserved
16
Reserved
17
Reserved
18
Reserved
19
Power Input
+10-32VDC
20
Reserved
21
Reserved
22
Reserved
23
Reserved
24
Reserved
25
Reserved
26
Reserved
Table 1 Unit Connector Pin Identification
The Multifunction Digital Attitude Indicator also provides ARINC outputs of the following data:
Label
Parameter
Units
LSB
MSB
Resolution
Min
Max
Xmit period
0325 (213d)
Roll
deg
15
29
0.010986328
-180.0
180.0
0.02 sec
0324 (212d)
Pitch
deg
16
29
0.021972656
-180.0
180.0
0.02 sec
0320 (208d)
Heading
deg
17
29
0.043945312
-180.0
180.0
0.05 sec

MD23-342
User Guide
Mid-Continent Instruments and Avionics 4 User Guide UG342, Revision 1
October 11, 2022
3.1 CONFIGURATION AND SETUP
Enter Configuration Mode by pressing and holding the Control Knob while applying power to the
unit. For configuration and setup of standard unit functions, including dimming control options
and dimming curve definition, please refer to the IM.
Configuration settings specific to this unit are found within the User Configuration menu option.
The User Configuration items include two functions:
3.1.1 USER CONFIGURATION
Within the User Configuration Menu, the user can select to
either configure aircraft installation related options or
instrument display options
Turn the Control Knob to highlight the desired option and
press to select it.
3.1.2 CONFIGURE AIRCRAFT
The Configure Aircraft Menu contains aircraft installation
related options.
Turn the Control Knob to highlight the desired option and
press to select it.
3.1.2.1 PANEL TILT
Use the panel tilt adjustment to compensate for any front-to-
back tilt of the instrument as installed in the instrument
panel.
This screen will appear (for example) as shown in the first
illustration on the right when initially selected, before any
adjustment is made. The actual measured pitch angle is
displayed by the artificial horizon display.
The current panel tilt setting is shown at the bottom of the
screen in degrees. When the Control Knob is turned, the
digit that is highlighted in green will be changed and the
displayed pitch angle will change accordingly. Press the
Control Knob to advance to the next digit. The second
illustration on the right shows the panel tilt adjustment
display after the adjustment has been made.
The display will return to the Configure Aircraft menu when
the knob is pressed with the last digit highlighted.

MD23-342
User Guide
Mid-Continent Instruments and Avionics 5 User Guide UG342, Revision 1
October 11, 2022
3.1.2.2 PANEL ROLL
The panel roll adjustment screen functions basically the
same as the panel tilt adjustment screen. An example of this
screen before adjusting to compensate for a slight roll
misalignment in the instrument installation is shown at the
right. Press the Control Knob to select the digits and turn to
adjust.
The display will return to the Configure Aircraft menu when
the knob is pressed with the last digit highlighted.
3.1.2.3 EXIT
The last menu item on the Configure Aircraft Menu is EXIT. Highlighting and selecting the
Exit menu item will close the Configure Aircraft Menu and return to the User Configuration
Menu.
3.1.3 CONFIGURE DISPLAY
The Configure Display menu allows the user to select
various options that affect the appearance of the display. It
is illustrated on the right. The current setting for each of
these options is shown on the right side of the screen in
grey text. Each of these options is described in the
following subparagraphs.
Turn the Control Knob to highlight the option you wish to
change and press the knob to select that option.
3.1.3.1 HEADING
This option controls whether the heading digital display and tape are displayed at the bottom
of the screen. It this option is set to OFF, the heading will not be displayed and the slip
indicator will be displayed at the bottom of the screen. If this option is set to ON, the slip
indicator will be smaller and moved just above the heading tape on the left side of the screen.
Turn the Control Knob to change the heading display option and the display will change
accordingly. Press the knob to select the desired heading display option and the screen will
return to the Configure Display Menu.

MD23-342
User Guide
Mid-Continent Instruments and Avionics 6 User Guide UG342, Revision 1
October 11, 2022
3.1.3.2 SYMBOL
If you select the SYMBOL option from the Configure Display Menu, the screen will show an
example of the display appearance using the currently selected aircraft symbol.
The options are Delta, Split Delta, and Traditional as shown in the illustrations below.
Turn the Control Knob to change the aircraft symbol option and the display will change
accordingly. Press the knob to select the desired symbol and the screen will return to the
Configure Display Menu.
3.1.3.3 ROLL
If you select the ROLL option from the Configure Display Menu, the screen will show an
example of the display appearance using the currently selected roll display option.
The options are Fixed Pointer, and Fixed Scale, as shown in the illustrations below.
Turn the Control Knob to change the roll display option and the display will change
accordingly. Press the knob to select the desired option and the screen will return to the
Configure Display Menu.
3.1.3.4 EXIT
The last menu item on the Configure Display menu is EXIT. Highlighting and selecting the
Exit menu item will close the Configure Display Menu and return to the User Configuration
Menu
3.1.4 EXIT
The last menu item on the User Configuration menu is EXIT. Highlighting and selecting the
Exit menu item will close the User Configuration Menu and return to the Configuration Menu.

MD23-342
User Guide
Mid-Continent Instruments and Avionics 7 User Guide UG342, Revision 1
October 11, 2022
4.1 OPERATION
For operation of standard unit functions, including the Options Menu, manual brightness control,
Info page, and others, please refer to the IM.
4.1.1 PRIMARY DISPLAY PRESENTATION
In Flight Mode, the display is presented as shown in the example figures below.
Power on screen Normal Operation
(example)
Primary Function elements are defined as follows:
•Pitch Display
The pitch scale range is ±90 degrees with 10 degree
major graduations which have numeric labels and 5
degree minor graduations (up to ±35 degrees) which are
unlabeled. At extreme pitch attitudes where the display
shows only the ground or the sky, chevrons are displayed
which indicate the direction of the horizon (zero pitch).
•Roll Display
The roll display range is ±180 degrees. The roll scale has minor graduations at ±10 and
±20 degrees and major graduations at 0, ±30, ±45, and ±60 degrees. The 0 and ±45
degree graduations are triangles, the others are linear.
•Slip Display
The slip display is a typical “ball in tube” display.
•Turn Rate Display
The turn rate is displayed as an arc and uses the roll scale graduations as follows:
•For a two minute turn, the arc extends to the 30 degree roll graduation.
•For a one minute turn, the arc extends to the 60 degree roll graduation.

MD23-342
User Guide
Mid-Continent Instruments and Avionics 8 User Guide UG342, Revision 1
October 11, 2022
•Heading Display (optional)
The heading is displayed as a numeric digital readout and a
heading tape which scrolls left during right turns and right
during left turns.
When ARINC heading data, label 0320 or 014 is being
received and is valid, the display will show triangular “sync”
indicators on either side of the numeric heading display
pointing inwards. The illustration to the right shows an
example of this.
•Error Annunciations
oRed X –displayed if sensor input limits are exceeded
or internal error limits are exceeded in the attitude
calculations. When these limits are no longer
exceeded, the unit will transition back to normal
attitude display mode. It may take several seconds
after the display transitions back to normal attitude
display mode for the attitude to completely recover to
full accuracy.
oLoss of Heading Aiding
If the ARINC heading data is lost, the “sync” indicators will disappear. After several
seconds, if the data is not recovered, the heading tape will disappear, and the
heading digital display will show three grey dashes. See the illustrations below for
examples.
4.1.2 USER OPTIONS
The artificial horizon display instrument does not have any in-flight configurable user options.

MD23-342
User Guide
Mid-Continent Instruments and Avionics 9 User Guide UG342, Revision 1
October 11, 2022
5.1 CONFORMANCE
For standard conformance items such as qualification levels and software updates, please refer
to the IM.
5.1.1 INSTRUCTIONS FOR CONTINUED AIRWORTHINESS
For this application, the MD23 is configured to process and display data associated with a
temperature and altitude compensated inertial measurement unit. Some aviation regulations
may apply to inspect and test for accuracy on a regular basis. (for example, 14 CFR §91.411
for altimeters) Please identify and/or refer to the appropriate maintenance procedures for
your aircraft in the pilot operating handbook or flight manual supplement.
5.1.2 COMPONENT MAINTENANCE AND REPAIR
No periodic scheduled maintenance or calibration is necessary for continued airworthiness of
the MD23 Custom Function Display, unless specified in the aircraft maintenance procedures,
as referenced above in 5.1.1.
The unit display can be cleaned using a lint-free cloth moistened with water. No chemicals
should be used to clean the display.
If the unit fails to perform to specifications, the unit must be removed and serviced by Mid-
Continent Instruments and Avionics or their authorized designee. Other than software version
updates or in-field calibration, there are no repairable parts or processes available to be
performed in the field.