Narrative:

7/cc inbound, false resolution alert in VMC. 7/clearance delivery IMC departure. At 1200 ft MSL 'descend' RA 2 targets (+2000 ft) 1 O'clock less than 3 mi. Initiated descent, targets disappeared. Resumed climb, went VMC at 1500-1600 ft MSL, same 2 targets, 200 ft above within 3 mi appeared on TCASII with 'descend' RA again. After confirming with ATC that there was no traffic in our vicinity we continued our climb with no further RA's. The military is conducting operations off the coast there. Every time they do we get these false RA's. In VMC it's a nuisance, but IMC, it's a safety factor, a big one. If it's their equipment, it needs work. If it's some E3 playing games, well, either way, big problem -- needs fixing. Callback conversation with reporter revealed the following information: reporter clarified the report by stating the following. Whenever a military ship is off shore, her aircraft receives false TCASII RA signals. The TCASII RA appears for about 30 seconds, then disappears. The RA does not coincide exactly with the ship, but will be about 1-2 mi from the ship. If a helicopter or formation of helicopters are seen flying from shore to ship, they will also generate a TCASII signal in the vicinity of the helicopter. The false RA signals never coincide with the object, just appear close by, and last no longer than 30 seconds. When these false signals appear in VMC the reporter doesn't mind because they can usually be verified to not exist by the flight crew visual observation and TRACON. When it's IMC, then they have to follow the commands for maximum safety. Reporter states other flight crew members have also experienced the same type of phenomena. It only happens when ships are participating in military maneuvers.

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Original NASA ASRS Text

Title: A SAAB 340 HAS SEVERAL FALSE TCASII RA DURING ARR AND DEP INTO CRQ, CA. RPTR ASSOCIATES THIS WITH MIL OPS AT SEA. WHEN THE SHIPS ARE AT SEA, THE TCASII RA ARE PLENTIFUL AND ARE FALSE.

Narrative: 7/CC INBOUND, FALSE RESOLUTION ALERT IN VMC. 7/CD IMC DEP. AT 1200 FT MSL 'DSND' RA 2 TARGETS (+2000 FT) 1 O'CLOCK LESS THAN 3 MI. INITIATED DSCNT, TARGETS DISAPPEARED. RESUMED CLB, WENT VMC AT 1500-1600 FT MSL, SAME 2 TARGETS, 200 FT ABOVE WITHIN 3 MI APPEARED ON TCASII WITH 'DSND' RA AGAIN. AFTER CONFIRMING WITH ATC THAT THERE WAS NO TFC IN OUR VICINITY WE CONTINUED OUR CLB WITH NO FURTHER RA'S. THE MIL IS CONDUCTING OPS OFF THE COAST THERE. EVERY TIME THEY DO WE GET THESE FALSE RA'S. IN VMC IT'S A NUISANCE, BUT IMC, IT'S A SAFETY FACTOR, A BIG ONE. IF IT'S THEIR EQUIP, IT NEEDS WORK. IF IT'S SOME E3 PLAYING GAMES, WELL, EITHER WAY, BIG PROB -- NEEDS FIXING. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR CLARIFIED THE RPT BY STATING THE FOLLOWING. WHENEVER A MIL SHIP IS OFF SHORE, HER ACFT RECEIVES FALSE TCASII RA SIGNALS. THE TCASII RA APPEARS FOR ABOUT 30 SECONDS, THEN DISAPPEARS. THE RA DOES NOT COINCIDE EXACTLY WITH THE SHIP, BUT WILL BE ABOUT 1-2 MI FROM THE SHIP. IF A HELI OR FORMATION OF HELIS ARE SEEN FLYING FROM SHORE TO SHIP, THEY WILL ALSO GENERATE A TCASII SIGNAL IN THE VICINITY OF THE HELI. THE FALSE RA SIGNALS NEVER COINCIDE WITH THE OBJECT, JUST APPEAR CLOSE BY, AND LAST NO LONGER THAN 30 SECONDS. WHEN THESE FALSE SIGNALS APPEAR IN VMC THE RPTR DOESN'T MIND BECAUSE THEY CAN USUALLY BE VERIFIED TO NOT EXIST BY THE FLC VISUAL OBSERVATION AND TRACON. WHEN IT'S IMC, THEN THEY HAVE TO FOLLOW THE COMMANDS FOR MAX SAFETY. RPTR STATES OTHER FLC MEMBERS HAVE ALSO EXPERIENCED THE SAME TYPE OF PHENOMENA. IT ONLY HAPPENS WHEN SHIPS ARE PARTICIPATING IN MIL MANEUVERS.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.