TCAS transmissions
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Joined: Jan 2015
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From: Riga
TCAS transmissions
Does anyone know the data frame format for interrogation and replies in TCAS ? It would be great if you can give me any info on Mode-S, Mode-C and Mode-A. Tried googling but didn't turn out proper results. Please help
Joined: Jan 2000
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From: FL410
Try reading up first on Eurocontrol website, it has many links.
For frame format manufacturer documentation or system description is required.
For frame format manufacturer documentation or system description is required.

Joined: Jul 2008
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From: EDDF
Take look at the Minimum Operational Performance Standards for TCAS II. This document defines the TCAS message formats.
The document can be obtained through RTCA as document DO-185,latest revision is DO-185B, change 2. Or through EUROCAE as document ED-143.
Mode S is defined in RTCA DO-181 (E)/ EUROCAE ED- 73 (E), latest revision is
ADS-B is defined in RTCA DO-260 (B) / EUROCAE ED-102 (A)
The document can be obtained through RTCA as document DO-185,latest revision is DO-185B, change 2. Or through EUROCAE as document ED-143.
Mode S is defined in RTCA DO-181 (E)/ EUROCAE ED- 73 (E), latest revision is
ADS-B is defined in RTCA DO-260 (B) / EUROCAE ED-102 (A)
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