Narrative:

On descent to sna; RNAV arrival was changed from dsnee 3; to rooby 3 due to landing direction at sna. We were cleared to descend via the rooby 3. We were subsequently issued a late clearance to cross roade at 16;000 ft or below. The profile descent was to cross roade between FL190 and 17;000 ft. We were only about 8 to 10 miles to the intersection on the profile; but very high to comply with the late clearance. I deployed speedbrakes; selected vertical speed and between 4500 to 5000 FPM; but advised the first officer I didn't think we'd be able to comply given the short distance to the fix. He advised ATC of the situation and said we would do our best to make it. ATC responded he wanted to get us below climbing traffic in opposite direction. Shortly thereafter; we noticed the traffic on TCAS. It appeared to be an impending conflict. I reduced the rate of descent as traffic continued to climb and converge. We received the TCAS advisory followed immediately with a climb RA. We complied with the RA path change and advised ATC of our actions. Once clear of the traffic; we re-established the vertical path and continued the profile descent on the arrival. ATC stated they would investigate the opposite direction traffic.we received a late clearance that was very difficult if at all possible to make. Moreover; we were being cleared to hustle down to clear opposite direction traffic that was converging and climbing towards us. It seemed to us that it would have been better to assign us a level off and or off course vector to avoid the potential conflict. We were not sure whether ATC was in communication with the TCAS traffic in question.

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Original NASA ASRS Text

Title: B737 flight crew reported receiving a late crossing restriction from ATC that ultimately resulted in a TCAS RA.

Narrative: On descent to SNA; RNAV arrival was changed from DSNEE 3; to ROOBY 3 due to landing direction at SNA. We were cleared to descend via the ROOBY 3. We were subsequently issued a late clearance to cross ROADE at 16;000 ft or below. The profile descent was to cross ROADE between FL190 and 17;000 ft. We were only about 8 to 10 miles to the intersection on the profile; but very high to comply with the late clearance. I deployed speedbrakes; selected Vertical Speed and between 4500 to 5000 FPM; but advised the First Officer I didn't think we'd be able to comply given the short distance to the fix. He advised ATC of the situation and said we would do our best to make it. ATC responded he wanted to get us below climbing traffic in opposite direction. Shortly thereafter; we noticed the traffic on TCAS. It appeared to be an impending conflict. I reduced the rate of descent as traffic continued to climb and converge. We received the TCAS advisory followed immediately with a Climb RA. We complied with the RA PATH change and advised ATC of our actions. Once clear of the traffic; we re-established the Vertical PATH and continued the profile descent on the arrival. ATC stated they would investigate the opposite direction traffic.We received a late clearance that was very difficult if at all possible to make. Moreover; we were being cleared to hustle down to clear opposite direction traffic that was converging and climbing towards us. It seemed to us that it would have been better to assign us a level off and or off course vector to avoid the potential conflict. We were not sure whether ATC was in communication with the TCAS traffic in question.

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.