Narrative:

While flying a ferry flight; we received a traffic call from ATC about a light airplane 500 feet below our altitude (6000MSL); and sometime later called traffic on an rj 1000 feet above. The captain said he had the light traffic below us; and then we immediately received a TCAS RA; 'climb; climb.' I deselected the autopilot and auto throttles and began a climb. At some point; I saw the target go from -4 to -3 on the nd TCAS display. The captain informed ATC that we were climbing in response to a RA. The ATC controller said; 'don't climb.' while this was happening; I received a TCAS adjust vertical speed warning. I adjusted the pitch attitude (down) to decrease the aircraft's pitch attitude to remain inside the RA guidance on the pfd. Then the captain said he had the rj in sight and pointed. When I visually acquired the rj; we were in level flight. I waited for the clear of conflict aural indication; and then I descended to 6000 feet. This whole event was very quick. I am estimating less than ten seconds from the first TCAS RA 'climb; climb' until the 'clear of conflict.' a turn from ATC in any direction would have prevented the three airplanes from being in such close proximity. I think we usually train to TCAS ras with a conflict from a single aircraft. We were sandwiched with an aircraft 500 feet below in a slight climb and constrained by one above.

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Original NASA ASRS Text

Title: A B737NG experienced two TCAS RAs within seconds with a light plane 500 feet below them and a CRJ 1000 feet above.

Narrative: While flying a ferry flight; we received a traffic call from ATC about a light airplane 500 feet below our altitude (6000MSL); and sometime later called traffic on an RJ 1000 feet above. The Captain said he had the light traffic below us; and then we immediately received a TCAS RA; 'Climb; climb.' I deselected the autopilot and auto throttles and began a climb. At some point; I saw the target go from -4 to -3 on the ND TCAS display. The Captain informed ATC that we were climbing in response to a RA. The ATC Controller said; 'Don't climb.' While this was happening; I received a TCAS Adjust Vertical Speed warning. I adjusted the pitch attitude (down) to decrease the aircraft's pitch attitude to remain inside the RA guidance on the PFD. Then the Captain said he had the RJ in sight and pointed. When I visually acquired the RJ; we were in level flight. I waited for the Clear of Conflict Aural indication; and then I descended to 6000 feet. This whole event was very quick. I am estimating less than ten seconds from the first TCAS RA 'Climb; climb' until the 'Clear of Conflict.' A turn from ATC in any direction would have prevented the three airplanes from being in such close proximity. I think we usually train to TCAS RAs with a conflict from a single aircraft. We were sandwiched with an aircraft 500 feet below in a slight climb and constrained by one above.

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.