Narrative:

A new piece of equipment in test mode; caused a number of IFR aircraft to change their route of departure; at the last min. Juneau area wind system is new and unique to juneau airport. It reports turbulence advisories based on wind sensors and algorithms (letter to airman 05-1). The phraseology required implies that this is 'real time; real life' information. Example: 'runway 26 arrival severe turbulence for a B737.' on this day; the machine was reporting gastineau channel surface to 6000 ft severe turbulence for a B737. This is the departure corridor to the east of the airport. When given this report; B737 said he could not fly into reported severe turbulence. Even with the equipment being in a live test cycle; the pilot did not feel comfortable taking the planned departure (departing runway 8 straight out to the east; through gastineau channel). The B737 ended up taking approximately a 13 KT tailwind and going 20 NM out of the way to avoid possible turbulence (departed runway 26 straight out to the west). This route also overlapped a SIGMET for severe turbulence below 4000 ft to the west of juneau airport. I understand the pilot had little choice in his response. I feel it is unwise to test this equipment in this way. This is the first live display and I think there should be better phraseology on the FAA's part to indicate that this is advisory only. In the 2 weeks it has been here; there has not been 1 PIREP that experienced the same level of turbulence being reported by juneau area wind system; and many reports for much less turbulence.

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Original NASA ASRS Text

Title: JNU TWR RPTR EXPRESSED CONCERN REGARDING WIND TEST EQUIP (JUNEAU AREA WIND SYS; JAWS) BEING EVALUATED AT JNU AND THE EFFECT ON TFC FLOW(S).

Narrative: A NEW PIECE OF EQUIP IN TEST MODE; CAUSED A NUMBER OF IFR ACFT TO CHANGE THEIR RTE OF DEP; AT THE LAST MIN. JUNEAU AREA WIND SYS IS NEW AND UNIQUE TO JUNEAU ARPT. IT RPTS TURB ADVISORIES BASED ON WIND SENSORS AND ALGORITHMS (LETTER TO AIRMAN 05-1). THE PHRASEOLOGY REQUIRED IMPLIES THAT THIS IS 'REAL TIME; REAL LIFE' INFO. EXAMPLE: 'RWY 26 ARR SEVERE TURB FOR A B737.' ON THIS DAY; THE MACHINE WAS RPTING GASTINEAU CHANNEL SURFACE TO 6000 FT SEVERE TURB FOR A B737. THIS IS THE DEP CORRIDOR TO THE E OF THE ARPT. WHEN GIVEN THIS RPT; B737 SAID HE COULD NOT FLY INTO RPTED SEVERE TURB. EVEN WITH THE EQUIP BEING IN A LIVE TEST CYCLE; THE PLT DID NOT FEEL COMFORTABLE TAKING THE PLANNED DEP (DEPARTING RWY 8 STRAIGHT OUT TO THE E; THROUGH GASTINEAU CHANNEL). THE B737 ENDED UP TAKING APPROX A 13 KT TAILWIND AND GOING 20 NM OUT OF THE WAY TO AVOID POSSIBLE TURB (DEPARTED RWY 26 STRAIGHT OUT TO THE W). THIS RTE ALSO OVERLAPPED A SIGMET FOR SEVERE TURB BELOW 4000 FT TO THE W OF JUNEAU ARPT. I UNDERSTAND THE PLT HAD LITTLE CHOICE IN HIS RESPONSE. I FEEL IT IS UNWISE TO TEST THIS EQUIP IN THIS WAY. THIS IS THE FIRST LIVE DISPLAY AND I THINK THERE SHOULD BE BETTER PHRASEOLOGY ON THE FAA'S PART TO INDICATE THAT THIS IS ADVISORY ONLY. IN THE 2 WKS IT HAS BEEN HERE; THERE HAS NOT BEEN 1 PIREP THAT EXPERIENCED THE SAME LEVEL OF TURB BEING RPTED BY JUNEAU AREA WIND SYS; AND MANY RPTS FOR MUCH LESS TURB.

Data retrieved from NASA's ASRS site as of January 2009 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.