Manual Number 9019161
Revision A, September 9, 2020
7
SECTION 2
PRE-INSTALLATION CONSIDERATIONS
COOLING
No external cooling is required. The unit will generate some heat as a function of normal operation.
Installation in an area that is exposed to extreme heat or restricted airflow can reduce the expected
life of the product. Mounting the unit to a metal surface can help reduce the effects of temperature
on the unit but is not required.
EQUIPMENT LOCATION
The MD23 FLEX
is designed primarily to be installed in the instrument panel of the aircraft. The unit
has an extra-wide viewing angle allowing for flexible installation location. When selecting a panel
location for the MD23, be sure to consider appropriate field-of-view with regard to pilot and/or co-
pilot visibility and accessibility. Other locations may be acceptable if the environmental qualifications
are considered with respect to the installation approval.
Additionally, consider what equipment is behind the panel that could impede the installation.
Clearance for the unit as well as its electrical and pneumatic connections (if present) and routing
must be allowed.
ROUTING OF CABLES
Be aware of routing cables near other electronics or with other wire bundles that may be
susceptible to high energy flow. Avoid sharp bends in cabling and routing near aircraft control
cables. Also avoid proximity and contact with aircraft structures, avionics equipment, or other
obstructions that could chafe wires or hoses during flight and cause undesirable effects.
LIMITATIONS
The MD23 FLEX
series of CFDs is certified to multiple FAA/EASA TSOs with the following
limitations identified:
environmental qualification conditions and requirements of each TSO are replaced with the
current and applicable procedures of RTCA/DO-160, revision G, and the equivalent or
better levels as identified within this manual
Applicable TSOs:
Technical Standard Order Authorization to FAA TSO C113b applies to all versions of the MD23.
TSOs C2d, C10c, and 106 only apply to the version(s) of the MD23 with pneumatic inputs. Further,
those TSOs are only applicable to customized configurations of the unit that represent the major
functions of each TSO. See the individual User Guide associated with each customized
configuration (CID) as to whether a particular TSO applies.
The MD23 contains a rechargeable manganese lithium coin cell for the purpose of maintaining non-
volatile memory. Per RTCA/DO-311A, the cell is an Energy Category 1 (0.051Wh < 2 Wh) and is
certified to UL 1642, thus certification to RTCA/DO-311A is not required. Specific STC limitations or
ACO coordination is not required for product or installation qualification.
