Narrative:

On approach to atl, there were some thunderstorms on the arrival route. 1 controller was most helpful in letting us deviate. There must have been a mixup on the handoff as the next guy wanted to know what we were doing. He gave us a turn to return to the published arrival route that would have put us right in a thunderstorm. It took 2 requests to get him to let us deviate. Turning final we were below the base of the clouds but could not see the field because of a heavy rain shaft just outside the marker. The cell producing the shift had heavy contour on the radar. Other aircraft were reporting heavy/moderate rain in this shaft. At this point I was making some strong assumptions, contour cell, high bases, small well-derived rain shaft. Are not those all signs of a pending or possible microburst? We could see that if we would slide just left of course and maybe be south of the OM by only a 1/2 mi we could avoid the rain shaft, stay VFR and land. I had the first officer tell tower our intentions. He got a roger and I started to move south. Just as we rounded the shaft, a different voice came on tower and broke us out of the pattern. We complied, then asked why tower said that in a parallel approach situation we had exceeded the parameters to continue. Keep in mind we went south. The other runway was to the north. We were then vectored around, given improper holding instructions (just a fix, no direction, etc). We had several calls from approach telling us that other aircraft were flying through the rain with no problems. I told them that when the rain shaft cleared we'd try again. In short, I resented the attempts to intimidate me, but my respect for thunderstorms is stronger than my pride/ego, and I really think the tower approach control people need to understand what thunderstorms can do to aircraft performance.

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Original NASA ASRS Text

Title: FLT CREW WX AVOIDANCE TSTM ACTIVITY.

Narrative: ON APCH TO ATL, THERE WERE SOME TSTMS ON THE ARR RTE. 1 CTLR WAS MOST HELPFUL IN LETTING US DEVIATE. THERE MUST HAVE BEEN A MIXUP ON THE HDOF AS THE NEXT GUY WANTED TO KNOW WHAT WE WERE DOING. HE GAVE US A TURN TO RETURN TO THE PUBLISHED ARR RTE THAT WOULD HAVE PUT US RIGHT IN A TSTM. IT TOOK 2 REQUESTS TO GET HIM TO LET US DEVIATE. TURNING FINAL WE WERE BELOW THE BASE OF THE CLOUDS BUT COULD NOT SEE THE FIELD BECAUSE OF A HEAVY RAIN SHAFT JUST OUTSIDE THE MARKER. THE CELL PRODUCING THE SHIFT HAD HEAVY CONTOUR ON THE RADAR. OTHER ACFT WERE RPTING HVY/MODERATE RAIN IN THIS SHAFT. AT THIS POINT I WAS MAKING SOME STRONG ASSUMPTIONS, CONTOUR CELL, HIGH BASES, SMALL WELL-DERIVED RAIN SHAFT. ARE NOT THOSE ALL SIGNS OF A PENDING OR POSSIBLE MICROBURST? WE COULD SEE THAT IF WE WOULD SLIDE JUST LEFT OF COURSE AND MAYBE BE S OF THE OM BY ONLY A 1/2 MI WE COULD AVOID THE RAIN SHAFT, STAY VFR AND LAND. I HAD THE F/O TELL TWR OUR INTENTIONS. HE GOT A ROGER AND I STARTED TO MOVE S. JUST AS WE ROUNDED THE SHAFT, A DIFFERENT VOICE CAME ON TWR AND BROKE US OUT OF THE PATTERN. WE COMPLIED, THEN ASKED WHY TWR SAID THAT IN A PARALLEL APCH SITUATION WE HAD EXCEEDED THE PARAMETERS TO CONTINUE. KEEP IN MIND WE WENT S. THE OTHER RWY WAS TO THE N. WE WERE THEN VECTORED AROUND, GIVEN IMPROPER HOLDING INSTRUCTIONS (JUST A FIX, NO DIRECTION, ETC). WE HAD SEVERAL CALLS FROM APCH TELLING US THAT OTHER ACFT WERE FLYING THROUGH THE RAIN WITH NO PROBS. I TOLD THEM THAT WHEN THE RAIN SHAFT CLRED WE'D TRY AGAIN. IN SHORT, I RESENTED THE ATTEMPTS TO INTIMIDATE ME, BUT MY RESPECT FOR TSTMS IS STRONGER THAN MY PRIDE/EGO, AND I REALLY THINK THE TWR APCH CTL PEOPLE NEED TO UNDERSTAND WHAT TSTMS CAN DO TO ACFT PERFORMANCE.

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.