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|
Attributes | |
ACN | 285021 |
Time | |
Date | 199410 |
Day | Thu |
Local Time Of Day | 1201 To 1800 |
Place | |
Locale Reference | atc facility : las |
State Reference | NV |
Altitude | msl bound lower : 29000 msl bound upper : 29500 |
Environment | |
Flight Conditions | VMC |
Light | Daylight |
Aircraft 1 | |
Controlling Facilities | artcc : zla tracon : clt |
Operator | common carrier : air carrier |
Make Model Name | B727-200 |
Operating Under FAR Part | Part 121 |
Flight Phase | climbout : intermediate altitude |
Route In Use | enroute : on vectors |
Flight Plan | IFR |
Aircraft 2 | |
Operator | common carrier : air carrier |
Make Model Name | Medium Large Transport, Low Wing, 2 Turbojet Eng |
Flight Phase | descent other |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : second officer |
Qualification | pilot : atp pilot : cfi pilot : flight engineer |
Experience | flight time last 90 days : 206 flight time total : 6900 flight time type : 3500 |
ASRS Report | 285021 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Qualification | pilot : instrument pilot : commercial pilot : cfi pilot : atp pilot : flight engineer |
Experience | flight time last 90 days : 170 flight time total : 19500 flight time type : 15000 |
ASRS Report | 284802 |
Events | |
Anomaly | conflict : airborne less severe non adherence : clearance non adherence : required legal separation other anomaly other |
Independent Detector | aircraft equipment other aircraft equipment : unspecified other controllera other flight crewa |
Resolutory Action | controller : issued new clearance flight crew : exited adverse environment flight crew : took evasive action |
Consequence | faa : reviewed incident with flight crew faa : investigated |
Supplementary | |
Primary Problem | ATC Human Performance |
Air Traffic Incident | Operational Error Pilot Deviation |
Situations | |
ATC Facility | procedure or policy : unspecified |
Narrative:
We were navigating on J146 (54 degrees) at FL290. We requested FL330. ATC (ZLA) gave us a 010 degree heading and climb to FL330. The first officer acknowledged. Then ATC said to maintain 1500 FPM or greater. I set the climb EPR and the captain established a climb. Shortly after the climb was established the TCASII issued a TA 'traffic,' followed by a RA 'descend, descend.' the captain slowly and smoothly stopped the climb, and began a descent. I suggested to the first officer to tell ATC that we were following an 'RA,' while at the same time, ATC instructed us to turn to a 340 degree heading (immediately). While in the turn to 340 degrees, the first officer picked up visual contact with the other aircraft, a 737, when on the 340 degree heading the TCASII issued 'clear of conflict' and we resumed climb to FL330. I feel that the primary cause of this incident was the controller's giving us a climb clearance with inadequate space with a descending aircraft. This may have been a 'real' space problem or one perceived by the TCASII unit. Compounding the problem was conflicting, confusing information. ATC was instructing us to climb, while the TCASII was instructing us to descend. There was also the uncertainty of what action (if any) the other aircraft might take. Our reaction to this (TCASII RA) was probably slowed a bit due to this conflicting information and our attempts to evaluate it. If we followed the initial TCASII, a bit more aggressively, perhaps, there may not have been a loss of separation (although there may have been injured flight attendants and passenger). The ATC controller was quick to recognize the situation and give us a turn (rather than insisting on climb). Supplemental information from acn 284802: another aircraft was descending toward us, copilot had aircraft in sight after the RA. ATC called me at home next day to advise they had a loss of separation possibly due to pilots following their TCASII. I don't know if this would have avoided the problem but I was a little slow to respond to the TCASII as the autoplt was trimmed for a good climb and I found it hard to change the attitude of autoplt. I should have pushed the nose down harder, but also, I didn't want to bounce passenger off the ceiling.
Original NASA ASRS Text
Title: CONFLICTING ATC INSTRUCTIONS WITH REF TO TCASII RA ON OPPOSITE DIRECTION DSNDING TFC.
Narrative: WE WERE NAVIGATING ON J146 (54 DEGS) AT FL290. WE REQUESTED FL330. ATC (ZLA) GAVE US A 010 DEG HDG AND CLB TO FL330. THE FO ACKNOWLEDGED. THEN ATC SAID TO MAINTAIN 1500 FPM OR GREATER. I SET THE CLB EPR AND THE CAPT ESTABLISHED A CLB. SHORTLY AFTER THE CLB WAS ESTABLISHED THE TCASII ISSUED A TA 'TFC,' FOLLOWED BY A RA 'DSND, DSND.' THE CAPT SLOWLY AND SMOOTHLY STOPPED THE CLB, AND BEGAN A DSCNT. I SUGGESTED TO THE FO TO TELL ATC THAT WE WERE FOLLOWING AN 'RA,' WHILE AT THE SAME TIME, ATC INSTRUCTED US TO TURN TO A 340 DEG HDG (IMMEDIATELY). WHILE IN THE TURN TO 340 DEGS, THE FO PICKED UP VISUAL CONTACT WITH THE OTHER ACFT, A 737, WHEN ON THE 340 DEG HDG THE TCASII ISSUED 'CLR OF CONFLICT' AND WE RESUMED CLB TO FL330. I FEEL THAT THE PRIMARY CAUSE OF THIS INCIDENT WAS THE CTLR'S GIVING US A CLB CLRNC WITH INADEQUATE SPACE WITH A DSNDING ACFT. THIS MAY HAVE BEEN A 'REAL' SPACE PROB OR ONE PERCEIVED BY THE TCASII UNIT. COMPOUNDING THE PROB WAS CONFLICTING, CONFUSING INFO. ATC WAS INSTRUCTING US TO CLB, WHILE THE TCASII WAS INSTRUCTING US TO DSND. THERE WAS ALSO THE UNCERTAINTY OF WHAT ACTION (IF ANY) THE OTHER ACFT MIGHT TAKE. OUR REACTION TO THIS (TCASII RA) WAS PROBABLY SLOWED A BIT DUE TO THIS CONFLICTING INFO AND OUR ATTEMPTS TO EVALUATE IT. IF WE FOLLOWED THE INITIAL TCASII, A BIT MORE AGGRESSIVELY, PERHAPS, THERE MAY NOT HAVE BEEN A LOSS OF SEPARATION (ALTHOUGH THERE MAY HAVE BEEN INJURED FLT ATTENDANTS AND PAX). THE ATC CTLR WAS QUICK TO RECOGNIZE THE SIT AND GIVE US A TURN (RATHER THAN INSISTING ON CLB). SUPPLEMENTAL INFO FROM ACN 284802: ANOTHER ACFT WAS DSNDING TOWARD US, COPLT HAD ACFT IN SIGHT AFTER THE RA. ATC CALLED ME AT HOME NEXT DAY TO ADVISE THEY HAD A LOSS OF SEPARATION POSSIBLY DUE TO PLTS FOLLOWING THEIR TCASII. I DON'T KNOW IF THIS WOULD HAVE AVOIDED THE PROB BUT I WAS A LITTLE SLOW TO RESPOND TO THE TCASII AS THE AUTOPLT WAS TRIMMED FOR A GOOD CLB AND I FOUND IT HARD TO CHANGE THE ATTITUDE OF AUTOPLT. I SHOULD HAVE PUSHED THE NOSE DOWN HARDER, BUT ALSO, I DIDN'T WANT TO BOUNCE PAX OFF THE CEILING.
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.