Honeywell International Inc. DMA-37B2 Manual De Usuario

Page 6

10 Oct 2007

DMA-37B DME System

© Honeywell International Inc. Do not copy without express permission of Honeywell.

Basic Unit

A microprocessor-based distance measuring equipment used to determine the 

slant-range distance as measured from the aircraft to a selected ground-based DME
transponder. Derived distance information is made available for visual display to the 

pilot, and for use by an automatic flight control system.
Design conforms to ARINC 709-8 and EUROCAE ED-54; digital guidance data output 

ports (binary digital distance, BCD digital distance and BCD channel selected) 

conforms to ARINC 429 format; two digital input ports for frequency/function select 

data input and source select capability operate in accordance with ARINC 429.
In addition to the automatic self-test feature, the unit contains an operator-initiated 

self-test feature, located on the DMA-37B front panel, that provides a comprehensive 

test of all sections of the unit and operation of its outputs.
The -1101 and -1212 units feature LEDs. The other dash numbers have an LCD 

display.
Complies with DO-178B software requirements and enhanced BITE requirements of 

Airbus, Boeing, and McDonnell Douglas.
With the exclusion of -1101 and -1212 the remaining dash numbers are capable of data 

recording and loading through the front of the unit.
Meets D0-160C lightning protection and 200 ms power interrupt transparency 

requirements. The -1101 and -1212 units are also rated for DO-160E operation.
Meets HIRF requirements and ICAO Annex 10 requirements.

Fault Memory

A nonvolatile, single-chip fault memory that allows the recording of faults associated 

with a particular flight leg. Sixty-four flight legs are available with each flight leg made 

up of a flight-leg information header containing a fault record section for recording
ten airborne faults and three ground faults. When all flight legs have been used, the 

oldest flight leg is reused.

CMC Interface

The DMA-37B interfaces fault memory and BITE data between DME Interrogator and 

line maintenance Centralized Maintenance Computer (CMC) for the purpose of 

extracting maintenance information and initiating tests. Designed to conform with 

ARINC 429 interfaces and ARINC 604.

CFDS Interface

The DMA-37B interfaces fault memory and BITE data between DME Interrogator and 

line maintenance Centralized Fault Display Interface Unit (CFDIU) for the purpose of 

extracting maintenance information and initiating tests. Designed to conform with 

ARINC 429 interfaces, ARINC 604 and Airbus Industrie ABDO048C or McDonnell 

Douglas software requirements

Digital Morse Code

Provides capability of receiving ground-facility digital Morse Code Ident signals and 

decoding them to ARINC 429 data word format for use on the DME Interrogator system 

ARINC 429 data output bus.

Multichannel Ident

Valid station identification is output for all foreground channels simultaneously, BCD 

distance is output only for the display channel (unless no display channel is selected), 

and output label 035 has its SSM set to NCD in standby mode; otherwise, without 

multichannel ident, valid station identification is output for the Ident channel only, BCD 

distance is output for all foreground channels (only the display channel is valid), and 

output label 035 has its SSM set to NORMAL in standby mode.