Narrative:

Approx. 20 east of rlg VOR cleared for the localizer FMS 25 into ege. Cleared to cross rlg at 15000 and cleared for the approach. We were descending through about 20;500 when we got a climb resolution advisory (RA) with no prior traffic advisory (TA) warning and no prior display of the traffic. Two targets appeared at 10 o'clock and less than 5 miles. They were initially red and indicating -800 and -500. We disconnected autoflight systems and followed the climb RA guidance. We advised den center we were climbing in response to an RA and they said the only traffic in our area was a flight of two B-1's but that they were assigned 1000 above our altitude. At the closest point the red symbols showed the aircraft -100 and -200 [feet] and directly below us on the 5 mile scale. The symbols then disappeared and the climb RA went away. The traffic then reappeared in white approximately 800 [feet] above us. I have no idea what sort of ability the B-1's have to slew their position to other aircrafts TCAS systems but it sure seems like they were doing something screwy with electronics. The really scary part is that we had climb guidance which has us headed right for them if they were indeed 1000 [feet] above us. We never saw the traffic due to the cloud layers. The denver controller asked the B-1s to confirm their altitude but we did not hear the response. They were obviously on a different frequency. The controller told us they had confirmed they were above us and asked if we saw them. We said no.

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Original NASA ASRS Text

Title: B737 flight crew experiences a false TCAS RA to climb apparently generated by two B-1's above the B737. After initially climbing the RA switches to a descent.

Narrative: Approx. 20 east of RLG VOR cleared for the LOC FMS 25 into EGE. Cleared to cross RLG at 15000 and cleared for the approach. We were descending through about 20;500 when we got a Climb resolution advisory (RA) with no prior traffic advisory (TA) warning and no prior display of the traffic. Two targets appeared at 10 o'clock and less than 5 miles. They were initially red and indicating -800 and -500. We disconnected autoflight systems and followed the CLIMB RA guidance. We advised DEN center we were climbing in response to an RA and they said the only traffic in our area was a flight of TWO B-1's but that they were assigned 1000 above our altitude. At the closest point the red symbols showed the aircraft -100 and -200 [feet] and directly below us on the 5 mile scale. The symbols then disappeared and the climb RA went away. The traffic then reappeared in white approximately 800 [feet] ABOVE us. I have no idea what sort of ability the B-1's have to slew their position to other aircrafts TCAS systems but it sure seems like they were doing something screwy with electronics. The really scary part is that we had CLIMB guidance which has us headed right for them if they were indeed 1000 [feet] above us. We never saw the traffic due to the cloud layers. The Denver controller asked the B-1s to confirm their altitude but we did not hear the response. They were obviously on a different frequency. The controller told us they had confirmed they were above us and asked if we saw them. We said no.

Data retrieved from NASA's ASRS site 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.