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Reporter in a B727 was cleared to land runway 24L. A saab, behind the B727, was cleared to land runway 24R. The saab got close enough to trigger the TCASII that commanded the B727 to descend which was impossible due to the proximity of terrain.
| Attributes | |
| ACN | 362847 |
| Time | |
| Date | 199703 |
| Day | Fri |
| Local Time Of Day | 1801 To 2400 |
| Place | |
| Locale Reference | airport : lax |
| State Reference | CA |
| Altitude | msl bound lower : 1000 msl bound upper : 1000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Night |
| Aircraft 1 | |
| Controlling Facilities | tower : lax |
| Operator | common carrier : air carrier |
| Make Model Name | B727 Undifferentiated or Other Model |
| Operating Under FAR Part | Part 121 |
| Flight Phase | descent : approach |
| Flight Plan | IFR |
| Aircraft 2 | |
| Operator | common carrier : air carrier |
| Make Model Name | Saab-Scania Undifferentiated or Other Model |
| Operating Under FAR Part | Part 121 |
| Flight Phase | descent : approach |
| Route In Use | approach : straight in |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 370 flight time total : 19100 flight time type : 450 |
| ASRS Report | 362847 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : instrument pilot : commercial |
| Events | |
| Anomaly | conflict : airborne less severe |
| Independent Detector | aircraft equipment other aircraft equipment : unspecified |
| Resolutory Action | none taken : anomaly accepted |
| Consequence | Other |
| Supplementary | |
| Primary Problem | Flight Crew Human Performance |
| Air Traffic Incident | Pilot Deviation |
Narrative:
This was a routine flight until we were handed off from socal approach to lax tower. We were cleared for the approach to runway 24L and received clearance to land from lax tower. Lax tower cleared a saab for runway 24R, but not to pass us on the left. At 1000 ft above touchdown, the TCASII alert announced 'traffic, descend now.' at this time we were concentrating on the approach, and this was a very distracting announcement. I thought we had an aircraft just above us. We did not have room to descend and not knowing where this aircraft was, I did not feel like the missed approach option was available. The first officer glanced outside his window and said that the saab aircraft was tucked in close to us on our right wing. I told the copilot to go for the runway, still not sure that was the aircraft that triggered the alert. A normal landing was made. On deplaning, a non revenue passenger told me the TCASII alert could be heard in first class seats. The first officer and I called the lax control tower to find out what was going on. The tower said that socal feeds in these commuter aircraft to them and they have little control. These aircraft are cleared for approach but not to pass the parallel aircraft. They may have some cowboy pilots that try to join on us which results on TCASII alerts. This could be highly dangerous. What would happen if you had to make a missed approach and wake turbulence flipped the saab or other little aircraft? What if you lost an engine and then turned into the path of the other aircraft? Lax has very close parallel runways on both the north and south sides. Side- by-side aircraft can set off TCASII alerts.
Original NASA ASRS Text
Title: RPTR IN A B727 WAS CLRED TO LAND RWY 24L. A SAAB, BEHIND THE B727, WAS CLRED TO LAND RWY 24R. THE SAAB GOT CLOSE ENOUGH TO TRIGGER THE TCASII THAT COMMANDED THE B727 TO DSND WHICH WAS IMPOSSIBLE DUE TO THE PROX OF TERRAIN.
Narrative: THIS WAS A ROUTINE FLT UNTIL WE WERE HANDED OFF FROM SOCAL APCH TO LAX TWR. WE WERE CLRED FOR THE APCH TO RWY 24L AND RECEIVED CLRNC TO LAND FROM LAX TWR. LAX TWR CLRED A SAAB FOR RWY 24R, BUT NOT TO PASS US ON THE L. AT 1000 FT ABOVE TOUCHDOWN, THE TCASII ALERT ANNOUNCED 'TFC, DSND NOW.' AT THIS TIME WE WERE CONCENTRATING ON THE APCH, AND THIS WAS A VERY DISTRACTING ANNOUNCEMENT. I THOUGHT WE HAD AN ACFT JUST ABOVE US. WE DID NOT HAVE ROOM TO DSND AND NOT KNOWING WHERE THIS ACFT WAS, I DID NOT FEEL LIKE THE MISSED APCH OPTION WAS AVAILABLE. THE FO GLANCED OUTSIDE HIS WINDOW AND SAID THAT THE SAAB ACFT WAS TUCKED IN CLOSE TO US ON OUR R WING. I TOLD THE COPLT TO GO FOR THE RWY, STILL NOT SURE THAT WAS THE ACFT THAT TRIGGERED THE ALERT. A NORMAL LNDG WAS MADE. ON DEPLANING, A NON REVENUE PAX TOLD ME THE TCASII ALERT COULD BE HEARD IN FIRST CLASS SEATS. THE FO AND I CALLED THE LAX CTL TWR TO FIND OUT WHAT WAS GOING ON. THE TWR SAID THAT SOCAL FEEDS IN THESE COMMUTER ACFT TO THEM AND THEY HAVE LITTLE CTL. THESE ACFT ARE CLRED FOR APCH BUT NOT TO PASS THE PARALLEL ACFT. THEY MAY HAVE SOME COWBOY PLTS THAT TRY TO JOIN ON US WHICH RESULTS ON TCASII ALERTS. THIS COULD BE HIGHLY DANGEROUS. WHAT WOULD HAPPEN IF YOU HAD TO MAKE A MISSED APCH AND WAKE TURB FLIPPED THE SAAB OR OTHER LITTLE ACFT? WHAT IF YOU LOST AN ENG AND THEN TURNED INTO THE PATH OF THE OTHER ACFT? LAX HAS VERY CLOSE PARALLEL RWYS ON BOTH THE N AND S SIDES. SIDE- BY-SIDE ACFT CAN SET OFF TCASII ALERTS.
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.