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Air carrier crew deviates slightly off course without clearance to avoid WX. Unable to break in to frequency because of congestion to advise ARTCC.
| Attributes | |
| ACN | 479530 |
| Time | |
| Date | 200007 |
| Day | Tue |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | navaid : lvs.vortac |
| State Reference | NM |
| Altitude | msl single value : 31000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : zab.artcc |
| Operator | common carrier : air carrier |
| Make Model Name | B737-300 |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | other |
| Flight Phase | cruise : level |
| Flight Plan | IFR |
| Aircraft 2 | |
| Controlling Facilities | artcc : zab.artcc |
| Operator | common carrier : air carrier |
| Make Model Name | Commercial Fixed Wing |
| Operating Under FAR Part | Part 121 |
| Flight Phase | cruise : level |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 243 flight time total : 11340 flight time type : 5700 |
| ASRS Report | 479530 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 210 flight time total : 11000 |
| ASRS Report | 479531 |
| Events | |
| Anomaly | inflight encounter : weather non adherence : clearance other anomaly other other spatial deviation |
| Independent Detector | other controllerb |
| Resolutory Action | flight crew : returned to intended or assigned course other |
| Miss Distance | horizontal : 90000 vertical : 4000 |
| Supplementary | |
| Problem Areas | ATC Human Performance ATC Facility Flight Crew Human Performance |
| Primary Problem | ATC Facility |
Narrative:
I was flying the aircraft and made a small course change to avoid a cumulus cloud cell. We were on a direct course to zuni VOR before the deviation. We were waiting for a break on the ZAB frequency to inform them of our course change, but had to turn before we could ask permission. As we were turning back direct to course we were called by ZAB. ZAB asked why we deviated. We told them to avoid severe WX. The controller told us that we 'almost' caused a traffic conflict with another aircraft 4000 ft above our aircraft. There was no traffic on our TCASII display. ZAB controller told us not to deviate without permission. I did not see any conflict whatsoever. The only way I see to resolve this type of problem is have more radio frequency capacity.
Original NASA ASRS Text
Title: ACR CREW DEVIATES SLIGHTLY OFF COURSE WITHOUT CLRNC TO AVOID WX. UNABLE TO BREAK IN TO FREQ BECAUSE OF CONGESTION TO ADVISE ARTCC.
Narrative: I WAS FLYING THE ACFT AND MADE A SMALL COURSE CHANGE TO AVOID A CUMULUS CLOUD CELL. WE WERE ON A DIRECT COURSE TO ZUNI VOR BEFORE THE DEV. WE WERE WAITING FOR A BREAK ON THE ZAB FREQ TO INFORM THEM OF OUR COURSE CHANGE, BUT HAD TO TURN BEFORE WE COULD ASK PERMISSION. AS WE WERE TURNING BACK DIRECT TO COURSE WE WERE CALLED BY ZAB. ZAB ASKED WHY WE DEVIATED. WE TOLD THEM TO AVOID SEVERE WX. THE CTLR TOLD US THAT WE 'ALMOST' CAUSED A TFC CONFLICT WITH ANOTHER ACFT 4000 FT ABOVE OUR ACFT. THERE WAS NO TFC ON OUR TCASII DISPLAY. ZAB CTLR TOLD US NOT TO DEVIATE WITHOUT PERMISSION. I DID NOT SEE ANY CONFLICT WHATSOEVER. THE ONLY WAY I SEE TO RESOLVE THIS TYPE OF PROB IS HAVE MORE RADIO FREQ CAPACITY.
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.