Narrative:

Wayne county (operator of dtw), local FAA ATC, and our airline management entered into an agreement to allow takeoff and landing operations at dtw on runways 21L, C, right with tailwinds of up to 7 KTS. This is a test program in order to facilitate noise abatement on the communities north of dtw. We were not told that this program was planned nor that it in fact had been implemented until 'after the fact'. A flight information file (fif) company internal notice was available for a few days after the test commenced, but it was only posted briefly and unless you transited dtw as an air carrier crew member one of those 'few' days it was available you would have no idea it existed. Pilots of other domestic and international airlines, corporate pilots, or any military or GA pilots arriving at dtw would be completely unaware of this test program since there is nothing broadcast on the local ATIS or published in the FAA NOTAMS. The major risk to aviation safety however, lies in the discrepancy between the wind direction and velocity values reported on the ATIS (or by local ATC personnel via radio request) and the values observed 'real time' by pilots of aircraft equipped with INS or IRS units which instantaneously provide accurate, current wind information. I have heard pilot reports to ATC of tailwind components in excess of 15 KTS at 50' AGL while the ATC personnel reported '4 KTS'. Unfortunately, takeoffs and lndgs continued after those PIREPS on a 'business as usual hub-time' pace. In all my experience flying for this air carrier on various air carrier type aircraft (each of which has a maximum takeoff/landing tailwind component limit of 10 KTS), I have never received or heard instruction given on 'proper technique' for how low to descend before abandoning an approach when the tailwind component exceeds the maximum limit value. I guess it remains 'pilot's discretion' to determine where, during the latter stages of an approach (below 100' AGL perhaps?), it is prudent to go around.

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Original NASA ASRS Text

Title: ACR PLT ALLEGES INSTITUTION OF 'DOWNWIND' RWY OPERATIONS FOR NOISE ABATEMENT AT DTW UNSAFE.

Narrative: WAYNE COUNTY (OPERATOR OF DTW), LCL FAA ATC, AND OUR AIRLINE MGMNT ENTERED INTO AN AGREEMENT TO ALLOW TKOF AND LNDG OPS AT DTW ON RWYS 21L, C, R WITH TAILWINDS OF UP TO 7 KTS. THIS IS A TEST PROGRAM IN ORDER TO FACILITATE NOISE ABATEMENT ON THE COMMUNITIES N OF DTW. WE WERE NOT TOLD THAT THIS PROGRAM WAS PLANNED NOR THAT IT IN FACT HAD BEEN IMPLEMENTED UNTIL 'AFTER THE FACT'. A FLT INFO FILE (FIF) COMPANY INTERNAL NOTICE WAS AVAILABLE FOR A FEW DAYS AFTER THE TEST COMMENCED, BUT IT WAS ONLY POSTED BRIEFLY AND UNLESS YOU TRANSITED DTW AS AN ACR CREW MEMBER ONE OF THOSE 'FEW' DAYS IT WAS AVAILABLE YOU WOULD HAVE NO IDEA IT EXISTED. PLTS OF OTHER DOMESTIC AND INTL AIRLINES, CORPORATE PLTS, OR ANY MIL OR GA PLTS ARRIVING AT DTW WOULD BE COMPLETELY UNAWARE OF THIS TEST PROGRAM SINCE THERE IS NOTHING BROADCAST ON THE LCL ATIS OR PUBLISHED IN THE FAA NOTAMS. THE MAJOR RISK TO AVIATION SAFETY HOWEVER, LIES IN THE DISCREPANCY BTWN THE WIND DIRECTION AND VELOCITY VALUES RPTED ON THE ATIS (OR BY LCL ATC PERSONNEL VIA RADIO REQUEST) AND THE VALUES OBSERVED 'REAL TIME' BY PLTS OF ACFT EQUIPPED WITH INS OR IRS UNITS WHICH INSTANTANEOUSLY PROVIDE ACCURATE, CURRENT WIND INFO. I HAVE HEARD PLT RPTS TO ATC OF TAILWIND COMPONENTS IN EXCESS OF 15 KTS AT 50' AGL WHILE THE ATC PERSONNEL RPTED '4 KTS'. UNFORTUNATELY, TKOFS AND LNDGS CONTINUED AFTER THOSE PIREPS ON A 'BUSINESS AS USUAL HUB-TIME' PACE. IN ALL MY EXPERIENCE FLYING FOR THIS ACR ON VARIOUS ACR TYPE ACFT (EACH OF WHICH HAS A MAX TKOF/LNDG TAILWIND COMPONENT LIMIT OF 10 KTS), I HAVE NEVER RECEIVED OR HEARD INSTRUCTION GIVEN ON 'PROPER TECHNIQUE' FOR HOW LOW TO DSND BEFORE ABANDONING AN APCH WHEN THE TAILWIND COMPONENT EXCEEDS THE MAX LIMIT VALUE. I GUESS IT REMAINS 'PLT'S DISCRETION' TO DETERMINE WHERE, DURING THE LATTER STAGES OF AN APCH (BELOW 100' AGL PERHAPS?), IT IS PRUDENT TO GO AROUND.

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.