Description and operation, Description, A. functional overview – ACR&Artex C406-N User Manual
Page 29

25-62-13
Page 29 of 109
MAR 1/13
ACR ELECTRONICS, INC / ARTEX PRODUCTS
DESCRIPTION, OPERATION, INSTALLATION AND MAINTENANCE MANUAL
C406-N (453-5060), C406-N HM (453-5061)
DESCRIPTION AND OPERATION
TASK 25-62-13-870-801
1. Description
SUBTASK 25-62-13-870-001
A. Functional Overview
(1)
The ELT automatically activates during a crash and transmits the standard sweep tone on
121.5 and 243.0 MHz. Approximately every 50 seconds, for up to 520 milliseconds (long
message protocol), the 406 MHz transmitter turns on. During that time, an encoded digital
message is sent to the COSPAS-SARSAT Search and Rescue (SAR) satellite system.
(2)
The information contained in the message includes:
(a)
Serial number assigned to the ELT by the beacon manufacturer or the national beacon
registration authority, or
(b)
Aircraft identification (24-bit address) or registration number, and
NOTE: When the optional C406-N Programming Adapter (PA) is installed, ELTs can be
moved between aircraft and the PA reprograms the ELT with either the aircraft
24-bit address or registration number. See Appendix B – Programming Adapter
(c)
Country of registration and country code; plus
(d)
Position coordinates provided by the aircraft navigation system.
NOTE: The C406-N Series ELT supports ARINC 429 data bus formats for receiving
position data from the aircraft navigation system. Other formats, such as RS-
232, RS-422, etc., are not supported.
(3)
The 406 MHz transmitter will operate for 24 hours and then shuts down automatically. The
121.5/243.0 transmitter will continue to operate until the batteries are exhausted, which is
typically at least 50 hours.
(4)
The 406 MHz transmitter produces a much more accurate position, typically 3 kilometers as
compared with 15 to 20 kilometers for 121.5/243.0 MHz transmitters. When coupled to the
aircraft navigation system, the accuracy improves to approximately 100 meters.
(5)
The ELT transmits a digital message that allows search and rescue authorities to contact the
owner/operator of the aircraft through information contained in a database. Information
contained in the database includes:
(a)
Type of aircraft and aircraft registration number,
(b)
Owner address and telephone number, and
(c)
Alternate emergency contact.