Narrative:

This event concerns me because of lack of response of center controller personnel. I was required to take action west/O clearance because ZDV controller in center told me twice to 'standby', but continued to accept new requests from airline pilots. I then initiated a climb to change altitude for strictly safety of flight reasons and announced my intentions to ZDV. Then they finally responded, but later were concerned that I had begun to change altitude west/O clearance. (They aren't the ones who die in airplanes that go through thunderstorms). I was inbound to denver IFR at 21000' with my wife to go to a mfr's pilot training school which I attend annually. We were in and out of clouds. Suddenly, I see depicited on radar a blotch of red directly ahead of me. Then we popped into the clear and I see a huge cumulus tentacular thunderstorm formation directly ahead. I immediately contacted ZDV saying 'ZDV, aircraft identification request, over'. Denver replied, 'aircraft identification standby'. They were taking similar requests from airlines which they always give priority to. I repeated my call a few seconds later. They repeated theirs exactly again. For safety of flight I then said 'ZDV, aircraft identification, I must climb to avoid a thunderstorm and will accept an on-top clearance. I can climb in VFR conditions'. I began a climb. Denver then said 'what level will you need?' I said '23-24 thousand'. Denver said 'your'e cleared to 23000''. I said 'roger' and continued to 23000'. A few moments later on approach to colorado springs, I was asked to call center on the ground. I did and talked to a shift chief. He wanted to know why I was observed on center radar at 21.7 when my clearance was 21. I explained what had happened and asked him to listen the center tape. He said he would. He suggested I should have declared an emergency, but I disagreed.

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Original NASA ASRS Text

Title: GA SMT ALT DEVIATION EXCURSION FROM CLRNC ALT TO AVOID TSTM BUILD UP.

Narrative: THIS EVENT CONCERNS ME BECAUSE OF LACK OF RESPONSE OF CTR CTLR PERSONNEL. I WAS REQUIRED TO TAKE ACTION W/O CLRNC BECAUSE ZDV CTLR IN CTR TOLD ME TWICE TO 'STANDBY', BUT CONTINUED TO ACCEPT NEW REQUESTS FROM AIRLINE PLTS. I THEN INITIATED A CLB TO CHANGE ALT FOR STRICTLY SAFETY OF FLT REASONS AND ANNOUNCED MY INTENTIONS TO ZDV. THEN THEY FINALLY RESPONDED, BUT LATER WERE CONCERNED THAT I HAD BEGUN TO CHANGE ALT W/O CLRNC. (THEY AREN'T THE ONES WHO DIE IN AIRPLANES THAT GO THROUGH TSTMS). I WAS INBND TO DENVER IFR AT 21000' WITH MY WIFE TO GO TO A MFR'S PLT TRNING SCHOOL WHICH I ATTEND ANNUALLY. WE WERE IN AND OUT OF CLOUDS. SUDDENLY, I SEE DEPICITED ON RADAR A BLOTCH OF RED DIRECTLY AHEAD OF ME. THEN WE POPPED INTO THE CLR AND I SEE A HUGE CUMULUS TENTACULAR TSTM FORMATION DIRECTLY AHEAD. I IMMEDIATELY CONTACTED ZDV SAYING 'ZDV, ACFT ID REQUEST, OVER'. DENVER REPLIED, 'ACFT ID STANDBY'. THEY WERE TAKING SIMILAR REQUESTS FROM AIRLINES WHICH THEY ALWAYS GIVE PRIORITY TO. I REPEATED MY CALL A FEW SECS LATER. THEY REPEATED THEIRS EXACTLY AGAIN. FOR SAFETY OF FLT I THEN SAID 'ZDV, ACFT ID, I MUST CLB TO AVOID A TSTM AND WILL ACCEPT AN ON-TOP CLRNC. I CAN CLB IN VFR CONDITIONS'. I BEGAN A CLB. DENVER THEN SAID 'WHAT LEVEL WILL YOU NEED?' I SAID '23-24 THOUSAND'. DENVER SAID 'YOUR'E CLRED TO 23000''. I SAID 'ROGER' AND CONTINUED TO 23000'. A FEW MOMENTS LATER ON APCH TO COLORADO SPRINGS, I WAS ASKED TO CALL CTR ON THE GND. I DID AND TALKED TO A SHIFT CHIEF. HE WANTED TO KNOW WHY I WAS OBSERVED ON CTR RADAR AT 21.7 WHEN MY CLRNC WAS 21. I EXPLAINED WHAT HAD HAPPENED AND ASKED HIM TO LISTEN THE CTR TAPE. HE SAID HE WOULD. HE SUGGESTED I SHOULD HAVE DECLARED AN EMER, BUT I DISAGREED.

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.