Narrative:

On being vectored for final approach, approach controller gave us 120 degree heading to intercept final approach course runway 9R and to descend from 10,000 to 3000. Upon intercepting localizer there was a thunderstorm right on the localizer course so the copilot deviated approximately 1/2 mi south to avoid WX. In the meantime I was attempting to tell the controller of our flight deviation but there was a steady stream of conversation on approach control. Upon learning of our flight path deviation, the controller became somewhat upset that he was not informed. I stated 'we could not get a word in edgewise.' my personal opinion is that this frequency during peak periods is too busy for one controller to handle. Apparently he had traffic at 4000' approximately 4 mi south of the localizer course that we were in possible conflict with since we were descending from 10,000' to 3000'. Although we were VFR and never saw our traffic as it was still 3 mi south of us the controller had us expedite through 4000'. Although there was no near miss the controller was mildly upset that he was not told of the deviation and I was mildly upset that I could not 'break-in' on the steady stream of conversation to tell him that we were deviating!

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Original NASA ASRS Text

Title: LGT ON ILS LOCALIZER DEVIATED ONE HALF MILE SOUTH TO AVOID TSTM ON LOCALIZER, UNABLE TO ADVISE TRACON ACCOUNT CROWDED FREQ.

Narrative: ON BEING VECTORED FOR FINAL APCH, APCH CTLR GAVE US 120 DEG HDG TO INTERCEPT FINAL APCH COURSE RWY 9R AND TO DSND FROM 10,000 TO 3000. UPON INTERCEPTING LOC THERE WAS A TSTM RIGHT ON THE LOC COURSE SO THE COPLT DEVIATED APPROX 1/2 MI S TO AVOID WX. IN THE MEANTIME I WAS ATTEMPTING TO TELL THE CTLR OF OUR FLT DEVIATION BUT THERE WAS A STEADY STREAM OF CONVERSATION ON APCH CTL. UPON LEARNING OF OUR FLT PATH DEVIATION, THE CTLR BECAME SOMEWHAT UPSET THAT HE WAS NOT INFORMED. I STATED 'WE COULD NOT GET A WORD IN EDGEWISE.' MY PERSONAL OPINION IS THAT THIS FREQ DURING PEAK PERIODS IS TOO BUSY FOR ONE CTLR TO HANDLE. APPARENTLY HE HAD TFC AT 4000' APPROX 4 MI S OF THE LOC COURSE THAT WE WERE IN POSSIBLE CONFLICT WITH SINCE WE WERE DESCENDING FROM 10,000' TO 3000'. ALTHOUGH WE WERE VFR AND NEVER SAW OUR TFC AS IT WAS STILL 3 MI S OF US THE CTLR HAD US EXPEDITE THROUGH 4000'. ALTHOUGH THERE WAS NO NEAR MISS THE CTLR WAS MILDLY UPSET THAT HE WAS NOT TOLD OF THE DEVIATION AND I WAS MILDLY UPSET THAT I COULD NOT 'BREAK-IN' ON THE STEADY STREAM OF CONVERSATION TO TELL HIM THAT WE WERE DEVIATING!

Data retrieved from NASA's ASRS site as of August 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.