Narrative:

While deviating around WX, with clearance from ATC, and by use of the aircraft radar, I was held down to FL230. I was unable to get my request for a higher altitude because of frequency congestion. As the radar was pointing up a few degrees for the climb, I came through an area of light precipitation and found myself in VFR conditions. However, there was a large buildup (circuit breaker) directly ahead and slightly above my altitude. Because of the intensity of the buildup, I decided it was safer to go over it in VFR conditions, which I did. While doing so, I exceeded my assigned altitude. I was too close to the buildup to deviate either right or left. Because I was in VFR conditions, I believed the altitude deviation to be a safer course of action than going into the top of a buildup of that intensity. ATC saw the altitude deviation and inquired about my altitude. I informed them that I was at FL240, but descending back down. They cleared me to maintain FL240, which I did. I believe that I should have had my radar more level and I would have been able to see the buildup sooner and I would have been able to deviate either to the right or to the left. The old problem of frequency congestion is still here and I have no idea how to solve that. Supplemental information from acn 120953: at the same time that I was identing our flight, the captain began his rapid climb above our cleared altitude. He did this so quickly that I couldn't tell center what our altitude was, nor point out to the captain that we could have flown to the left and easily avoided the circuit breaker horizontal. Shortly after busting the altitude cleared to, ZKC told the captain to call the center desk watch and explain why we did not level off at FL230.

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Original NASA ASRS Text

Title: ACR CAPT DEVIATES FROM ASSIGNED ALT WITHOUT INFORMING ATC.

Narrative: WHILE DEVIATING AROUND WX, WITH CLRNC FROM ATC, AND BY USE OF THE ACFT RADAR, I WAS HELD DOWN TO FL230. I WAS UNABLE TO GET MY REQUEST FOR A HIGHER ALT BECAUSE OF FREQ CONGESTION. AS THE RADAR WAS POINTING UP A FEW DEGS FOR THE CLB, I CAME THROUGH AN AREA OF LIGHT PRECIPITATION AND FOUND MYSELF IN VFR CONDITIONS. HOWEVER, THERE WAS A LARGE BUILDUP (CB) DIRECTLY AHEAD AND SLIGHTLY ABOVE MY ALT. BECAUSE OF THE INTENSITY OF THE BUILDUP, I DECIDED IT WAS SAFER TO GO OVER IT IN VFR CONDITIONS, WHICH I DID. WHILE DOING SO, I EXCEEDED MY ASSIGNED ALT. I WAS TOO CLOSE TO THE BUILDUP TO DEVIATE EITHER RIGHT OR LEFT. BECAUSE I WAS IN VFR CONDITIONS, I BELIEVED THE ALT DEVIATION TO BE A SAFER COURSE OF ACTION THAN GOING INTO THE TOP OF A BUILDUP OF THAT INTENSITY. ATC SAW THE ALT DEVIATION AND INQUIRED ABOUT MY ALT. I INFORMED THEM THAT I WAS AT FL240, BUT DSNDING BACK DOWN. THEY CLRED ME TO MAINTAIN FL240, WHICH I DID. I BELIEVE THAT I SHOULD HAVE HAD MY RADAR MORE LEVEL AND I WOULD HAVE BEEN ABLE TO SEE THE BUILDUP SOONER AND I WOULD HAVE BEEN ABLE TO DEVIATE EITHER TO THE RIGHT OR TO THE LEFT. THE OLD PROB OF FREQ CONGESTION IS STILL HERE AND I HAVE NO IDEA HOW TO SOLVE THAT. SUPPLEMENTAL INFO FROM ACN 120953: AT THE SAME TIME THAT I WAS IDENTING OUR FLT, THE CAPT BEGAN HIS RAPID CLB ABOVE OUR CLRED ALT. HE DID THIS SO QUICKLY THAT I COULDN'T TELL CENTER WHAT OUR ALT WAS, NOR POINT OUT TO THE CAPT THAT WE COULD HAVE FLOWN TO THE LEFT AND EASILY AVOIDED THE CB HORIZ. SHORTLY AFTER BUSTING THE ALT CLRED TO, ZKC TOLD THE CAPT TO CALL THE CENTER DESK WATCH AND EXPLAIN WHY WE DID NOT LEVEL OFF AT FL230.

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.