TCAS RA detection actually uses "TCAS Operational" bit

[DME-3]

Hello,

TCAS RA detection function tcas_ra in pyModeS/decoder/bds/bds62.py uses bit 52 of the target state and status information messages (TC = 29, BDS 6,2):

tcas_ra = True if int(mb[52]) == 1 else False

However, according to 2.2.3.2.7.1.3.17 of DO-260B, that bit is used for "TCAS Operational" status.

There is a TCAS RA active flag in the OM part of TC = 31 messages (aircraft operational status, message bit 27). This is BDS 6,5 which is not supported yet.

[xoolive]

Yes, note that this flag is actually always True 🤷 @junzis that's one of the things I fixed here 😜