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|
Attributes | |
ACN | 235836 |
Time | |
Date | 199303 |
Day | Mon |
Local Time Of Day | 0601 To 1200 |
Place | |
Locale Reference | atc facility : sna |
State Reference | CA |
Altitude | msl bound lower : 24000 msl bound upper : 25000 |
Environment | |
Flight Conditions | VMC |
Light | Daylight |
Aircraft 1 | |
Controlling Facilities | artcc : zla |
Operator | common carrier : air carrier |
Make Model Name | Medium Large Transport, Low Wing, 2 Turbojet Eng |
Flight Phase | climbout : intermediate altitude |
Flight Plan | IFR |
Aircraft 2 | |
Operator | other |
Make Model Name | Military Trainer |
Flight Phase | climbout : intermediate altitude |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Qualification | pilot : atp |
Experience | flight time last 90 days : 100 flight time total : 7300 flight time type : 500 |
ASRS Report | 235836 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : first officer |
Qualification | pilot : commercial pilot : instrument |
Events | |
Anomaly | aircraft equipment problem : critical other anomaly other |
Independent Detector | aircraft equipment other aircraft equipment : unspecified |
Resolutory Action | other |
Consequence | Other |
Supplementary | |
Primary Problem | Aircraft |
Air Traffic Incident | other |
Narrative:
We were cleared to FL330. There was traffic displayed level at FL230. ATC advised him that he would get higher, reference us. As we climbed through FL250, center cleared the traffic from FL230 to climb to FL240. His rapid climb from FL230 to FL240 caused our TCASII to provide an RA commanding a 1000-2000 FPM descent. The RA remained until the traffic passed beneath us, and off our left side. If we had complied with the RA, we would have descended into the conflicting traffic, rather than away from the intruder. Fortunately, we recognized what was happening, and did not follow the TCASII RA command. There would seem to be marginal benefit for the traffic to climb 1000 ft considering the fact that they would have been clear (and was clear) of us within a min or 2. If the controller had waited until we were diverging, the RA would not have occurred. It would appear that, if we had not seen the TCASII screen and figured out what the problem was, the TCASII would have reduced the separation rather than enhanced. We were lucky to have had good WX, and happened to have been watching the TCASII. This could have been a bad situation if we were IMC and had followed the RA.
Original NASA ASRS Text
Title: MLG HAS TCASII RA WHICH, IF FOLLOWED, WOULD PUT THEM IN THE PATH OF CLBING TFC.
Narrative: WE WERE CLRED TO FL330. THERE WAS TFC DISPLAYED LEVEL AT FL230. ATC ADVISED HIM THAT HE WOULD GET HIGHER, REF US. AS WE CLBED THROUGH FL250, CTR CLRED THE TFC FROM FL230 TO CLB TO FL240. HIS RAPID CLB FROM FL230 TO FL240 CAUSED OUR TCASII TO PROVIDE AN RA COMMANDING A 1000-2000 FPM DSCNT. THE RA REMAINED UNTIL THE TFC PASSED BENEATH US, AND OFF OUR L SIDE. IF WE HAD COMPLIED WITH THE RA, WE WOULD HAVE DSNDED INTO THE CONFLICTING TFC, RATHER THAN AWAY FROM THE INTRUDER. FORTUNATELY, WE RECOGNIZED WHAT WAS HAPPENING, AND DID NOT FOLLOW THE TCASII RA COMMAND. THERE WOULD SEEM TO BE MARGINAL BENEFIT FOR THE TFC TO CLB 1000 FT CONSIDERING THE FACT THAT THEY WOULD HAVE BEEN CLR (AND WAS CLR) OF US WITHIN A MIN OR 2. IF THE CTLR HAD WAITED UNTIL WE WERE DIVERGING, THE RA WOULD NOT HAVE OCCURRED. IT WOULD APPEAR THAT, IF WE HAD NOT SEEN THE TCASII SCREEN AND FIGURED OUT WHAT THE PROB WAS, THE TCASII WOULD HAVE REDUCED THE SEPARATION RATHER THAN ENHANCED. WE WERE LUCKY TO HAVE HAD GOOD WX, AND HAPPENED TO HAVE BEEN WATCHING THE TCASII. THIS COULD HAVE BEEN A BAD SIT IF WE WERE IMC AND HAD FOLLOWED THE RA.
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.