Narrative:

Line of thunderstorms east/west had passed over field from n-s. ILS runway 34 in use but line of WX across runway 34 localizer. Aircraft had been vectored 20 mi west around line for ILS runway 16. Aircraft sighted field and was cleared for visual at his request. Cleared aircraft to land runway 16, issued wind 040 degrees at 3 KTS. When aircraft was on 1/4 mi final, high and fast, pilot requested wind check. Procedures require wind to be issued off ASOS. Direct wind reading instruments are covered with a piece of paper. ASOS showed wind variable at 4 KTS. Thought this was suspect so took unauthorized glance under paper. Direct instrument read wind 360 degrees at 27 KTS gusting to 34 KTS. Reference light rain pelting north tower window had reason to believe this was accurate. Not authority/authorized to issue wind from direct instrument, and unable to issue ASOS wind in good conscience issued 'unable wind check go around.' put aircraft in left traffic for runway 34. When aircraft was on base for runway 34 ASOS wind read 300 degrees at 17 KTS gusting to 25 KTS. Issued this value to aircraft and cleared to land runway 34. When aircraft on final for runway 34 ASOS read wind 320 degrees at 25 KTS. By this time this agreed with direct instrument. Aircraft landed without incident. Noted that while aircraft was parking on ramp ASOS wind read wind 360 degrees at 27 KTS gusting to 34 KTS which agrees with what had been observed on the direct instrument confirming its (prior) accuracy. It is my understanding that the direct instruments are to be decommissioned. Have to ask what would have happened if they had been, or I had not taken the unauthorized look at them, or without my pilot experience had I not realized the significance of the pilot's wind check request being a request for real time wind, and issued ASOS wind. I believe this represents an unacceptable potentially dangerous situation. All resources should be used to full benefit. I believe this can be accomplished as follows: at ASOS locations wind should be issued from the ASOS per genot on this subject. Wind 'checks' should be issued from a certified direct reading instrument. National policy needs to be set. This is a simple matter. At ASOS locations wind issued is ASOS wind and the phraseology is 'wind xxxxxxx.' the phraseology 'wind xxxxxxx' to be defined as ASOS wind at these locations. Requests for wind checks or wind checks as controller deems appropriate shall be issued from the direct instruments. The phraseology 'wind check xxxxxxx' should be defined as real time wind issued from a direct reading instrument.

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Original NASA ASRS Text

Title: ATCT CTLR CLRED AN ACR BE02 FOR A VISUAL APCH TO RWY 16 BASED ON WIND INFO GIVEN BY THE ASOS. WHILE ON SHORT FINAL THE BE02 REQUESTED A WIND CHK AND THE CTLR USED THE DIRECT WIND INST WHICH INDICATED AN EXCESSIVE TAILWIND AND SENT THE ACFT AROUND. THE ACFT LANDED ON RWY 34 ON HIS SECOND APCH.

Narrative: LINE OF TSTMS E/W HAD PASSED OVER FIELD FROM N-S. ILS RWY 34 IN USE BUT LINE OF WX ACROSS RWY 34 LOC. ACFT HAD BEEN VECTORED 20 MI W AROUND LINE FOR ILS RWY 16. ACFT SIGHTED FIELD AND WAS CLRED FOR VISUAL AT HIS REQUEST. CLRED ACFT TO LAND RWY 16, ISSUED WIND 040 DEGS AT 3 KTS. WHEN ACFT WAS ON 1/4 MI FINAL, HIGH AND FAST, PLT REQUESTED WIND CHK. PROCS REQUIRE WIND TO BE ISSUED OFF ASOS. DIRECT WIND READING INSTS ARE COVERED WITH A PIECE OF PAPER. ASOS SHOWED WIND VARIABLE AT 4 KTS. THOUGHT THIS WAS SUSPECT SO TOOK UNAUTH GLANCE UNDER PAPER. DIRECT INST READ WIND 360 DEGS AT 27 KTS GUSTING TO 34 KTS. REF LIGHT RAIN PELTING N TWR WINDOW HAD REASON TO BELIEVE THIS WAS ACCURATE. NOT AUTH TO ISSUE WIND FROM DIRECT INST, AND UNABLE TO ISSUE ASOS WIND IN GOOD CONSCIENCE ISSUED 'UNABLE WIND CHK GAR.' PUT ACFT IN L TFC FOR RWY 34. WHEN ACFT WAS ON BASE FOR RWY 34 ASOS WIND READ 300 DEGS AT 17 KTS GUSTING TO 25 KTS. ISSUED THIS VALUE TO ACFT AND CLRED TO LAND RWY 34. WHEN ACFT ON FINAL FOR RWY 34 ASOS READ WIND 320 DEGS AT 25 KTS. BY THIS TIME THIS AGREED WITH DIRECT INST. ACFT LANDED WITHOUT INCIDENT. NOTED THAT WHILE ACFT WAS PARKING ON RAMP ASOS WIND READ WIND 360 DEGS AT 27 KTS GUSTING TO 34 KTS WHICH AGREES WITH WHAT HAD BEEN OBSERVED ON THE DIRECT INST CONFIRMING ITS (PRIOR) ACCURACY. IT IS MY UNDERSTANDING THAT THE DIRECT INSTS ARE TO BE DECOMMISSIONED. HAVE TO ASK WHAT WOULD HAVE HAPPENED IF THEY HAD BEEN, OR I HAD NOT TAKEN THE UNAUTH LOOK AT THEM, OR WITHOUT MY PLT EXPERIENCE HAD I NOT REALIZED THE SIGNIFICANCE OF THE PLT'S WIND CHK REQUEST BEING A REQUEST FOR REAL TIME WIND, AND ISSUED ASOS WIND. I BELIEVE THIS REPRESENTS AN UNACCEPTABLE POTENTIALLY DANGEROUS SIT. ALL RESOURCES SHOULD BE USED TO FULL BENEFIT. I BELIEVE THIS CAN BE ACCOMPLISHED AS FOLLOWS: AT ASOS LOCATIONS WIND SHOULD BE ISSUED FROM THE ASOS PER GENOT ON THIS SUBJECT. WIND 'CHKS' SHOULD BE ISSUED FROM A CERTIFIED DIRECT READING INST. NATIONAL POLICY NEEDS TO BE SET. THIS IS A SIMPLE MATTER. AT ASOS LOCATIONS WIND ISSUED IS ASOS WIND AND THE PHRASEOLOGY IS 'WIND XXXXXXX.' THE PHRASEOLOGY 'WIND XXXXXXX' TO BE DEFINED AS ASOS WIND AT THESE LOCATIONS. REQUESTS FOR WIND CHKS OR WIND CHKS AS CTLR DEEMS APPROPRIATE SHALL BE ISSUED FROM THE DIRECT INSTS. THE PHRASEOLOGY 'WIND CHK XXXXXXX' SHOULD BE DEFINED AS REAL TIME WIND ISSUED FROM A DIRECT READING INST.

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.