Narrative:

We were told to turn left and intercept the runway 17L localizer (we were at 20 mi at this point going through the localizer), we intercepted and I started to slow calling for flaps so as to cross the FAF on speed. I told the first officer and so that I was going to carry a little extra speed due the conditions (5 KTS for a total of 10 KTS) as there was rain between us and the runway, the visibility was 2 1/2 mi on ATIS. At approximately 1000 ft we encountered very heavy rain that intensified as we descended on the GS, the wipers were turned on but had very little effect. At 100 ft above minimums the engineer called approaching minimums, at 230 ft I did not have a very good picture of the runway and started to push the power up, at 200 ft I elected to go around and applied go around thrust calling for gear up and go around flaps (I could make out the runway and lights however it was only momentary between wiper sweeps and I was afraid I might lose it if I had elected to continue with the landing) we told the tower that we were going around. The gear was up and the flaps were set for go around when we got the windshear alert I applied firewall thrust and pitched up to approximately 22 degrees we were already flaps at 20 degrees and speed was at 140 KIAS the airspeed hung up at 140 KIAS and we did not climb much above 200 ft for 5 to 10 seconds, the tower called a center field microburst alert (which I believe we were in the middle of) after the encounter and climbing we notified the tower that we had encountered a severe windshear, I called for flaps 5 degrees speed of 170 KTS. We came around and had a normal landing on runway 34. The windshear training we are trained with was very effective. Some additional information I would like to add, I briefed the possibility of windshear and we would go around in the event of a microburst alert (I wanted to differentiate between advisories and an alert) even though it was not on the ATIS. I also carried 5 KTS extra which is something I do not normally do, I had started my go around at approximately 230 ft which put us in a better position with the gear and flaps set when we encountered the windshear, ie, upon the encounter we were already configured with the gear, flaps and power set for go around. Supplemental information from acn 447428: we had properly briefed and considered the WX as well as the possibility of having to use our alternate (cos). We were not surprised to see the thunderstorms in the denver area, and were aware of the potential for windshear. The captain briefed the approach ahead of time and we all talked about our concern with the close proximity of the storm to the airfield. Because of the location of the storm, near the southeast boundary, I believe tower was not experiencing the heavy rain. As a result, they would have been in a good position to observe the developing rain shaft, lightning, and gust front. The best decision from a safety standpoint I believe would have been to close runway 17L/right and land aircraft on runway 16, which was in the clear. The captain was using the ship's radar to try to get a good idea of the severity of the storm. He said he tilted the radar up to get rid of ground clutter and didn't see any red. He therefore, elected to continue, in view of the fact that another aircraft in front of us landed without problem and there were no severe WX reports coming from the tower.

Related reports:

Google
 

Original NASA ASRS Text

Title: A BOEING 727 FLC ENCOUNTERED A MICROBURST AND WINDSHEAR ON APCH TO DEN.

Narrative: WE WERE TOLD TO TURN L AND INTERCEPT THE RWY 17L LOC (WE WERE AT 20 MI AT THIS POINT GOING THROUGH THE LOC), WE INTERCEPTED AND I STARTED TO SLOW CALLING FOR FLAPS SO AS TO CROSS THE FAF ON SPD. I TOLD THE FO AND SO THAT I WAS GOING TO CARRY A LITTLE EXTRA SPD DUE THE CONDITIONS (5 KTS FOR A TOTAL OF 10 KTS) AS THERE WAS RAIN BTWN US AND THE RWY, THE VISIBILITY WAS 2 1/2 MI ON ATIS. AT APPROX 1000 FT WE ENCOUNTERED VERY HVY RAIN THAT INTENSIFIED AS WE DSNDED ON THE GS, THE WIPERS WERE TURNED ON BUT HAD VERY LITTLE EFFECT. AT 100 FT ABOVE MINIMUMS THE ENGINEER CALLED APCHING MINIMUMS, AT 230 FT I DID NOT HAVE A VERY GOOD PICTURE OF THE RWY AND STARTED TO PUSH THE PWR UP, AT 200 FT I ELECTED TO GO AROUND AND APPLIED GAR THRUST CALLING FOR GEAR UP AND GAR FLAPS (I COULD MAKE OUT THE RWY AND LIGHTS HOWEVER IT WAS ONLY MOMENTARY BTWN WIPER SWEEPS AND I WAS AFRAID I MIGHT LOSE IT IF I HAD ELECTED TO CONTINUE WITH THE LNDG) WE TOLD THE TWR THAT WE WERE GOING AROUND. THE GEAR WAS UP AND THE FLAPS WERE SET FOR GAR WHEN WE GOT THE WINDSHEAR ALERT I APPLIED FIREWALL THRUST AND PITCHED UP TO APPROX 22 DEGS WE WERE ALREADY FLAPS AT 20 DEGS AND SPD WAS AT 140 KIAS THE AIRSPD HUNG UP AT 140 KIAS AND WE DID NOT CLB MUCH ABOVE 200 FT FOR 5 TO 10 SECONDS, THE TWR CALLED A CTR FIELD MICROBURST ALERT (WHICH I BELIEVE WE WERE IN THE MIDDLE OF) AFTER THE ENCOUNTER AND CLBING WE NOTIFIED THE TWR THAT WE HAD ENCOUNTERED A SEVERE WINDSHEAR, I CALLED FOR FLAPS 5 DEGS SPD OF 170 KTS. WE CAME AROUND AND HAD A NORMAL LNDG ON RWY 34. THE WINDSHEAR TRAINING WE ARE TRAINED WITH WAS VERY EFFECTIVE. SOME ADDITIONAL INFO I WOULD LIKE TO ADD, I BRIEFED THE POSSIBILITY OF WINDSHEAR AND WE WOULD GO AROUND IN THE EVENT OF A MICROBURST ALERT (I WANTED TO DIFFERENTIATE BTWN ADVISORIES AND AN ALERT) EVEN THOUGH IT WAS NOT ON THE ATIS. I ALSO CARRIED 5 KTS EXTRA WHICH IS SOMETHING I DO NOT NORMALLY DO, I HAD STARTED MY GAR AT APPROX 230 FT WHICH PUT US IN A BETTER POS WITH THE GEAR AND FLAPS SET WHEN WE ENCOUNTERED THE WINDSHEAR, IE, UPON THE ENCOUNTER WE WERE ALREADY CONFIGURED WITH THE GEAR, FLAPS AND PWR SET FOR GAR. SUPPLEMENTAL INFO FROM ACN 447428: WE HAD PROPERLY BRIEFED AND CONSIDERED THE WX AS WELL AS THE POSSIBILITY OF HAVING TO USE OUR ALTERNATE (COS). WE WERE NOT SURPRISED TO SEE THE TSTMS IN THE DENVER AREA, AND WERE AWARE OF THE POTENTIAL FOR WINDSHEAR. THE CAPT BRIEFED THE APCH AHEAD OF TIME AND WE ALL TALKED ABOUT OUR CONCERN WITH THE CLOSE PROX OF THE STORM TO THE AIRFIELD. BECAUSE OF THE LOCATION OF THE STORM, NEAR THE SE BOUNDARY, I BELIEVE TWR WAS NOT EXPERIENCING THE HVY RAIN. AS A RESULT, THEY WOULD HAVE BEEN IN A GOOD POS TO OBSERVE THE DEVELOPING RAIN SHAFT, LIGHTNING, AND GUST FRONT. THE BEST DECISION FROM A SAFETY STANDPOINT I BELIEVE WOULD HAVE BEEN TO CLOSE RWY 17L/R AND LAND ACFT ON RWY 16, WHICH WAS IN THE CLR. THE CAPT WAS USING THE SHIP'S RADAR TO TRY TO GET A GOOD IDEA OF THE SEVERITY OF THE STORM. HE SAID HE TILTED THE RADAR UP TO GET RID OF GND CLUTTER AND DIDN'T SEE ANY RED. HE THEREFORE, ELECTED TO CONTINUE, IN VIEW OF THE FACT THAT ANOTHER ACFT IN FRONT OF US LANDED WITHOUT PROB AND THERE WERE NO SEVERE WX RPTS COMING FROM THE TWR.

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.