Narrative:

On departure climbout from phx was given 15;000 instead of filed 17;000 so assumed there was traffic issue. Shortly after level off abq ARTCC gave us traffic as 2 USAF T-38s at 10 to 11 o'clock; and 30 miles I believe; converging with our course level at 17;000 northwest bound. We stated we didn't see them but would be looking. We heard the controller give the T-38s an advisory on us. We did not hear their response and assumed they were UHF communication only. A few minutes later they must have reported us in sight and got a clearance to descend maintaining visual clearance with us. We were doing some in range check work at point. I looked at my mfd moving map and saw a blue target at our 10 o'clock at 16;300 with a descending indication. I queried the controller that the T-38s were maintaining their previous altitude. He responded negative they reported you in sight and are cleared to descend maintaining visual separation. I selected 20 miles on my moving map and the next return was well inside 10 miles; a red square indicating 15;300. At the same instant we got a descend RA command. I retarded power and pitched for what I thought a 2;000 ft per minute descent would be. We were at 300 KIAS. The next hit the incoming target was just over 6 miles at 14;700 and we were indicating 14;700; the next hit was at about 5 miles at 14;600 and we were indicating 14;600. The RA command changed at that point to climb. I aggressively pitched up added power. Our altitude bottomed out at 14;500 at the same instant the incoming target indicated 14;500. The next hit indicated 14;600 as we passed through 14;600. I realized they were now climbing as well and I rolled into a right 30 or 40 degree bank to attempt to gain lateral separation. As we passed through 14;700 the TCAS target was at 14;700 and was just off our left wing on the map display. Then the target vanished and the RA commands ceased. We overshot our original altitude to 15;300 before arresting our climb. We immediately advised ATC that our maneuvering was in response to TCAS RA guidance. The flight continued on to our destination without further incident. Upon conferring with ATC he stated that the 'with radar trace at maximum resolution it was impossible to tell whether the T-38s passed in front of or behind' our aircraft. The last we heard of the T-38 flight was a hand off to an AFB approach. At no time did we ever acquire the T-38s visually. Our total altitude deviation was -500 ft and +300 ft. The 100 ft vertical distance that we missed in the boxed data above is a guess since the last indicated altitude was identical to our own. Given the radar trace cannot depict whether the T-38s passed ahead or behind us they maintained a direct intercept track to our aircraft. We were passing from their right to their left at an angle of 30 to 40 degrees at nearly 390 KTS TAS. To pass that closely would have required that they maintained a track to intercept us and then began a descent on that intercept track. This does not indicate an intent to maintain separation from our aircraft. It would indicate an intent to make a relatively close approach to our aircraft. Even a 5 degree course change to their right would have taken them on a track that would have kept our TCAS from going into the RA maneuver alert mode.

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Original NASA ASRS Text

Title: ABQ ATC cleared two T-38's to descend after they reported visual contact with a CRJ but the trainers approached the passenger jet so closely the TCAS commanded a descent. The result was a NMAC.

Narrative: On departure climbout from PHX was given 15;000 instead of filed 17;000 so assumed there was traffic issue. Shortly after level off ABQ ARTCC gave us traffic as 2 USAF T-38s at 10 to 11 o'clock; and 30 miles I believe; converging with our course level at 17;000 northwest bound. We stated we didn't see them but would be looking. We heard the Controller give the T-38s an advisory on us. We did not hear their response and assumed they were UHF communication only. A few minutes later they must have reported us in sight and got a clearance to descend maintaining visual clearance with us. We were doing some in range check work at point. I looked at my MFD moving map and saw a blue target at our 10 o'clock at 16;300 with a descending indication. I queried the Controller that the T-38s were maintaining their previous altitude. He responded negative they reported you in sight and are cleared to descend maintaining visual separation. I selected 20 miles on my moving map and the next return was well inside 10 miles; a red square indicating 15;300. At the same instant we got a descend RA command. I retarded power and pitched for what I thought a 2;000 FT per minute descent would be. We were at 300 KIAS. The next hit the incoming target was just over 6 miles at 14;700 and we were indicating 14;700; the next hit was at about 5 miles at 14;600 and we were indicating 14;600. The RA command changed at that point to climb. I aggressively pitched up added power. Our altitude bottomed out at 14;500 at the same instant the incoming target indicated 14;500. The next hit indicated 14;600 as we passed through 14;600. I realized they were now climbing as well and I rolled into a right 30 or 40 degree bank to attempt to gain lateral separation. As we passed through 14;700 the TCAS target was at 14;700 and was just off our left wing on the map display. Then the target vanished and the RA commands ceased. We overshot our original altitude to 15;300 before arresting our climb. We immediately advised ATC that our maneuvering was in response to TCAS RA guidance. The flight continued on to our destination without further incident. Upon conferring with ATC he stated that the 'with radar trace at maximum resolution it was impossible to tell whether the T-38s passed in front of or behind' our aircraft. The last we heard of the T-38 flight was a hand off to an AFB approach. At no time did we ever acquire the T-38s visually. Our total altitude deviation was -500 FT and +300 FT. The 100 FT vertical distance that we missed in the boxed data above is a guess since the last indicated altitude was identical to our own. Given the radar trace cannot depict whether the T-38s passed ahead or behind us they maintained a direct intercept track to our aircraft. We were passing from their right to their left at an angle of 30 to 40 degrees at nearly 390 KTS TAS. To pass that closely would have required that they maintained a track to intercept us and then began a descent on that intercept track. This does not indicate an intent to maintain separation from our aircraft. It would indicate an intent to make a relatively close approach to our aircraft. Even a 5 degree course change to their right would have taken them on a track that would have kept our TCAS from going into the RA maneuver alert mode.

Data retrieved from NASA's ASRS site as of April 2012 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.