Narrative:

On approach to dca, numerous heavy rain showers were in the area. Ceilings were approximately 6000-7000 ft with 5 mi visibility and haze. I would describe the WX conditions as only rain showers, some heavy. On the entire approach, I witnessed no lightning of any kind (cloud to cloud, cloud to ground). We were vectored off the arrival for WX northwest of the field. On our first approach to runway 1, we were in visual flight conditions and cleared to land by the tower. Wind advisory was 'center field winds, 300 degrees/12 KTS, departure end 55 KTS.' I queried the controller again and he repeated the information. I told him I could not accept that clearance and would like to try another approach. We were given a right turn to 120 degrees, climb and maintain 3000 ft and vectored to the south for holding at the OM. During the climb out, we encountered heavy precipitation to the east briefly and had clear air to the south. All the time during the climb out, I was conflicted that I never heard a 'windshear alert' from the tower and did not witness anything visually that would indicate that kind of wind anomaly. After our turn back towards the airport at the OM, I could see on the WX radar that the line of WX had passed the airport to the south and that the final approach course appeared clear. I relayed this information to the controller, who agreed and said we could intercept final from our position for the ILS to runway 1. The runway and airfield were clearly in sight at the OM. We configured to land, knowing we had several threats in the immediate vicinity: 1) heavy rain showers, 2) numerous other aircraft holding at low altitude, 3) prohibited area P56 north of the field, 4) reported windshear within the last 20 mins. We again switched over to dca tower and reported the runway and were given a landing clearance. At approximately 1200 ft, tower said 'air carrier X, microburst alert -35 KTS, 3 mi south.' remember, we are in clear air. Dew point spread is 10 degrees, no turbulence of any kind, with the runway in sight. I queried tower again with the same response. I was conflicted with the first approach report and the second was just as puzzling. I was prepared to do another go around and concluded that at this point, the least threat option was to land the aircraft for the reason we wouldn't have to deal with items 1-4 above. The approach and touchdown were uneventful. In summary, the approach to dca is challenging on a clear day. The WX didn't seem to be as bad as the tower reports indicated. If in fact these events did occur as reported, I suspect that the data was very late in being delivered to the aircrew, that the wind and microburst advisories would have fit a pattern that would have been indicative of the first abandoned approach and not the last. Either I am missing something in my over 2 decades of flying experience in much worse WX than this -- or the reporting was fouled.

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Original NASA ASRS Text

Title: AN MD80 PLT QUESTIONS THE ACCURACY AND TIMELINESS OF WINDSHEAR AND MICROBURST ALERTS AT DCA.

Narrative: ON APCH TO DCA, NUMEROUS HVY RAIN SHOWERS WERE IN THE AREA. CEILINGS WERE APPROX 6000-7000 FT WITH 5 MI VISIBILITY AND HAZE. I WOULD DESCRIBE THE WX CONDITIONS AS ONLY RAIN SHOWERS, SOME HVY. ON THE ENTIRE APCH, I WITNESSED NO LIGHTNING OF ANY KIND (CLOUD TO CLOUD, CLOUD TO GND). WE WERE VECTORED OFF THE ARR FOR WX NW OF THE FIELD. ON OUR FIRST APCH TO RWY 1, WE WERE IN VISUAL FLT CONDITIONS AND CLRED TO LAND BY THE TWR. WIND ADVISORY WAS 'CTR FIELD WINDS, 300 DEGS/12 KTS, DEP END 55 KTS.' I QUERIED THE CTLR AGAIN AND HE REPEATED THE INFO. I TOLD HIM I COULD NOT ACCEPT THAT CLRNC AND WOULD LIKE TO TRY ANOTHER APCH. WE WERE GIVEN A R TURN TO 120 DEGS, CLB AND MAINTAIN 3000 FT AND VECTORED TO THE S FOR HOLDING AT THE OM. DURING THE CLBOUT, WE ENCOUNTERED HVY PRECIP TO THE E BRIEFLY AND HAD CLR AIR TO THE S. ALL THE TIME DURING THE CLBOUT, I WAS CONFLICTED THAT I NEVER HEARD A 'WINDSHEAR ALERT' FROM THE TWR AND DID NOT WITNESS ANYTHING VISUALLY THAT WOULD INDICATE THAT KIND OF WIND ANOMALY. AFTER OUR TURN BACK TOWARDS THE ARPT AT THE OM, I COULD SEE ON THE WX RADAR THAT THE LINE OF WX HAD PASSED THE ARPT TO THE S AND THAT THE FINAL APCH COURSE APPEARED CLR. I RELAYED THIS INFO TO THE CTLR, WHO AGREED AND SAID WE COULD INTERCEPT FINAL FROM OUR POS FOR THE ILS TO RWY 1. THE RWY AND AIRFIELD WERE CLRLY IN SIGHT AT THE OM. WE CONFIGURED TO LAND, KNOWING WE HAD SEVERAL THREATS IN THE IMMEDIATE VICINITY: 1) HVY RAIN SHOWERS, 2) NUMEROUS OTHER ACFT HOLDING AT LOW ALT, 3) PROHIBITED AREA P56 N OF THE FIELD, 4) RPTED WINDSHEAR WITHIN THE LAST 20 MINS. WE AGAIN SWITCHED OVER TO DCA TWR AND RPTED THE RWY AND WERE GIVEN A LNDG CLRNC. AT APPROX 1200 FT, TWR SAID 'ACR X, MICROBURST ALERT -35 KTS, 3 MI S.' REMEMBER, WE ARE IN CLR AIR. DEW POINT SPREAD IS 10 DEGS, NO TURB OF ANY KIND, WITH THE RWY IN SIGHT. I QUERIED TWR AGAIN WITH THE SAME RESPONSE. I WAS CONFLICTED WITH THE FIRST APCH RPT AND THE SECOND WAS JUST AS PUZZLING. I WAS PREPARED TO DO ANOTHER GAR AND CONCLUDED THAT AT THIS POINT, THE LEAST THREAT OPTION WAS TO LAND THE ACFT FOR THE REASON WE WOULDN'T HAVE TO DEAL WITH ITEMS 1-4 ABOVE. THE APCH AND TOUCHDOWN WERE UNEVENTFUL. IN SUMMARY, THE APCH TO DCA IS CHALLENGING ON A CLR DAY. THE WX DIDN'T SEEM TO BE AS BAD AS THE TWR RPTS INDICATED. IF IN FACT THESE EVENTS DID OCCUR AS RPTED, I SUSPECT THAT THE DATA WAS VERY LATE IN BEING DELIVERED TO THE AIRCREW, THAT THE WIND AND MICROBURST ADVISORIES WOULD HAVE FIT A PATTERN THAT WOULD HAVE BEEN INDICATIVE OF THE FIRST ABANDONED APCH AND NOT THE LAST. EITHER I AM MISSING SOMETHING IN MY OVER 2 DECADES OF FLYING EXPERIENCE IN MUCH WORSE WX THAN THIS -- OR THE RPTING WAS FOULED.

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.