37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
Attributes | |
ACN | 170772 |
Time | |
Date | 199102 |
Day | Wed |
Local Time Of Day | 0601 To 1200 |
Place | |
Locale Reference | airport : guc |
State Reference | CO |
Altitude | agl bound lower : 840 agl bound upper : 840 |
Environment | |
Flight Conditions | IMC |
Light | Daylight |
Aircraft 1 | |
Controlling Facilities | tower : den |
Operator | common carrier : air carrier |
Make Model Name | Large Transport, Low Wing, 3 Turbojet Eng |
Flight Phase | descent : approach descent other landing other |
Route In Use | approach : straight in |
Flight Plan | IFR |
Aircraft 2 | |
Operator | common carrier : air carrier |
Make Model Name | Light Transport |
Flight Phase | descent : approach landing other |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : second officer |
Qualification | pilot : cfi pilot : atp pilot : instrument pilot : flight engineer pilot : commercial |
Experience | flight time last 90 days : 225 flight time total : 3500 flight time type : 225 |
ASRS Report | 170772 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Qualification | pilot : atp |
Events | |
Anomaly | inflight encounter : weather other anomaly other |
Independent Detector | other flight crewa |
Resolutory Action | other |
Consequence | Other |
Supplementary | |
Primary Problem | Weather |
Air Traffic Incident | other |
Narrative:
During descent into gunnison, co, airport, WX was obtained on company frequency as specified in the operating procedures. The WX observation was taken from the AWOS and was reported as clear below 12000' with a visibility of 10 and winds from 240 degree at 12 gusting to 18 KTS. Based on this information we planned a visibility approach to runway 24. Shortly thereafter, we overheard a commuter airplane report to denver that he had 'broken out at minimums at gunnison.' we asked which minimums he meant and he stated the ILS to runway 6. I called the company to confirm the current WX and they reiterated the AWOS observation, further stating that it 'looked good' outside. Based on this conflicting information, we quickly briefed and flew the ILS to runway 6, anticipating a visibility circle to runway 24 due to the winds. We broke out under a ragged ceiling very close to ILS minimums (DH 840') and were too close to complete a visibility maneuver. A final wind check on short final was right at tailwind limits, and we completed a landing on runway 6. While the entire sequence of events terminated west/O incident, I'm reporting it because it could have had potentially deadly consequences. The WX observation we obtained put the entire crews into the mindset of making a relatively easy visibility approach in poor WX near mountains. The only warning we had that the WX was other then VMC near the airport was the unsolicited report from the commuter aircraft. Clearly the AWOS at gunnison was not providing accurate WX information at the time of this incident. Additionally, station personnel reported to us that the AWOS is often unreliable during rapidly changing WX conditions. It seems to me that a human observer should be present until the flaws can be worked out of this system. I felt extremely uncomfortable throughout the approach and landing and hope to avoid any repeat performances in the future. Callback conversation with reporter revealed the following information. Company has small operation at gunnison who gave 'looks good' report. This report came from a non pilot. Reporter feels ground personnel are not aware of hazard in mountainous area. Probably more concerned that they might have to bus passenger if land at alternate. Used to have WX observer on field, but no longer. Feels AWOS information should be kept current and updated as WX changes. If not for overhearing commuter aircraft, reporter aircraft would have flown to blue mesa VOR and tried to make a visibility approach due to WX information received. Crew very uncomfortable and feel poor WX information is dangerous in this mountain terrain. Has consulted with company management regarding situation.
Original NASA ASRS Text
Title: ACR RECEIVES POOR, INACCURATE WX INFO ON AWOS. REQUIRED TO MAKE IAP WITH TAILWIND AT LIMITS.
Narrative: DURING DSNT INTO GUNNISON, CO, ARPT, WX WAS OBTAINED ON COMPANY FREQ AS SPECIFIED IN THE OPERATING PROCS. THE WX OBSERVATION WAS TAKEN FROM THE AWOS AND WAS RPTED AS CLR BELOW 12000' WITH A VISIBILITY OF 10 AND WINDS FROM 240 DEG AT 12 GUSTING TO 18 KTS. BASED ON THIS INFO WE PLANNED A VIS APCH TO RWY 24. SHORTLY THEREAFTER, WE OVERHEARD A COMMUTER AIRPLANE RPT TO DENVER THAT HE HAD 'BROKEN OUT AT MINIMUMS AT GUNNISON.' WE ASKED WHICH MINIMUMS HE MEANT AND HE STATED THE ILS TO RWY 6. I CALLED THE COMPANY TO CONFIRM THE CURRENT WX AND THEY REITERATED THE AWOS OBSERVATION, FURTHER STATING THAT IT 'LOOKED GOOD' OUTSIDE. BASED ON THIS CONFLICTING INFO, WE QUICKLY BRIEFED AND FLEW THE ILS TO RWY 6, ANTICIPATING A VIS CIRCLE TO RWY 24 DUE TO THE WINDS. WE BROKE OUT UNDER A RAGGED CEILING VERY CLOSE TO ILS MINIMUMS (DH 840') AND WERE TOO CLOSE TO COMPLETE A VIS MANEUVER. A FINAL WIND CHK ON SHORT FINAL WAS R AT TAILWIND LIMITS, AND WE COMPLETED A LNDG ON RWY 6. WHILE THE ENTIRE SEQUENCE OF EVENTS TERMINATED W/O INCIDENT, I'M RPTING IT BECAUSE IT COULD HAVE HAD POTENTIALLY DEADLY CONSEQUENCES. THE WX OBSERVATION WE OBTAINED PUT THE ENTIRE CREWS INTO THE MINDSET OF MAKING A RELATIVELY EASY VIS APCH IN POOR WX NEAR MOUNTAINS. THE ONLY WARNING WE HAD THAT THE WX WAS OTHER THEN VMC NEAR THE ARPT WAS THE UNSOLICITED RPT FROM THE COMMUTER ACFT. CLRLY THE AWOS AT GUNNISON WAS NOT PROVIDING ACCURATE WX INFO AT THE TIME OF THIS INCIDENT. ADDITIONALLY, STATION PERSONNEL RPTED TO US THAT THE AWOS IS OFTEN UNRELIABLE DURING RAPIDLY CHANGING WX CONDITIONS. IT SEEMS TO ME THAT A HUMAN OBSERVER SHOULD BE PRESENT UNTIL THE FLAWS CAN BE WORKED OUT OF THIS SYS. I FELT EXTREMELY UNCOMFORTABLE THROUGHOUT THE APCH AND LNDG AND HOPE TO AVOID ANY REPEAT PERFORMANCES IN THE FUTURE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO. COMPANY HAS SMALL OPERATION AT GUNNISON WHO GAVE 'LOOKS GOOD' RPT. THIS RPT CAME FROM A NON PLT. RPTR FEELS GND PERSONNEL ARE NOT AWARE OF HAZARD IN MOUNTAINOUS AREA. PROBABLY MORE CONCERNED THAT THEY MIGHT HAVE TO BUS PAX IF LAND AT ALTERNATE. USED TO HAVE WX OBSERVER ON FIELD, BUT NO LONGER. FEELS AWOS INFO SHOULD BE KEPT CURRENT AND UPDATED AS WX CHANGES. IF NOT FOR OVERHEARING COMMUTER ACFT, RPTR ACFT WOULD HAVE FLOWN TO BLUE MESA VOR AND TRIED TO MAKE A VIS APCH DUE TO WX INFO RECEIVED. CREW VERY UNCOMFORTABLE AND FEEL POOR WX INFO IS DANGEROUS IN THIS MOUNTAIN TERRAIN. HAS CONSULTED WITH COMPANY MGMNT REGARDING SITUATION.
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.