In reply to:
TCAS systems must be set to TA mode (Traffic Alert only), rather than RA mode (Resolution Alert)…not a factor for TCAD (Skywatch) systems, which have no RA mode.
Matt,
The FAA recently changed the policy for using TCAS equipment during PRM. Previous guidance required pilots to select TA-only mode when conducting an ILS-PRM approach.
The FAA conducted a study determining TCAS equipment can be used in PRM as approved for other flight operations. Aircrews are no longer required to select TA only mode when conducting PRM approaches. The FAA determined TCAS operated in accordance with guidance (the same as with other operations in the NAS) are less likely to come into to conflict with another aircraft on the parallel course; should PRM controller separation standards fail. Aircrews must understand the ATC instruction is the primary means of separation. In the unlikely event a controller instruction is received simultaneous to a TCAS alert, pilots should always take the air traffic instruction to turn. If reaction to a TCAS alert causes the aircrew to deviate from an assigned clearance, they should inform ATC as soon as practical of their intentions.