Narrative:

First officer was flying the aircraft, descent was made from FL330 to FL290. Iah was temporarily closed to landing traffic due to thunderstorms arriving from the southwest. Fuel was starting to be a consideration due to the extended rerte and closure of iah. A clearance from FL290 to FL280 was given along with a vector to the west away from the airport. ATC radio traffic was extremely heavy with aircraft deviating for WX. The flight engineer was on the radio with company. I was on the radio copying holding instructions when I looked back at the altitude and noticed the aircraft at FL274. The assigned altitude was FL280. I told the first officer to get back to FL280 and he immediately did so. A lot was going on, but I have no excuse for the deviation. The first officer and I spoke about paying attention under all circumstances. I do not think this type of problem will occur again. Supplemental information from acn 441151: during setup of hold, we descended through FL280, our leveling required altitude. At FL276, I tried to recover with autoplt. Autoplt was slow to recover at FL274. I turned off autoplt and manually recovered and climbed back to assigned FL280. Cause of deviation was attributed to heavy workload, thunderstorm avoidance, heavy radio communication, 360 degree descending turn followed by holding instructions, strong turbulence, and VFR into IMC.

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Original NASA ASRS Text

Title: BEING VECTORED FOR DELAYS WHILE ARRS WERE STOPPED FOR TSTMS OVER ARPT, ACR CREW FAILED TO LEVEL AT ASSIGNED ALT DURING DSCNT. DISCOVERED AND CORRECTED.

Narrative: FO WAS FLYING THE ACFT, DSCNT WAS MADE FROM FL330 TO FL290. IAH WAS TEMPORARILY CLOSED TO LNDG TFC DUE TO TSTMS ARRIVING FROM THE SW. FUEL WAS STARTING TO BE A CONSIDERATION DUE TO THE EXTENDED RERTE AND CLOSURE OF IAH. A CLRNC FROM FL290 TO FL280 WAS GIVEN ALONG WITH A VECTOR TO THE W AWAY FROM THE ARPT. ATC RADIO TFC WAS EXTREMELY HVY WITH ACFT DEVIATING FOR WX. THE FE WAS ON THE RADIO WITH COMPANY. I WAS ON THE RADIO COPYING HOLDING INSTRUCTIONS WHEN I LOOKED BACK AT THE ALT AND NOTICED THE ACFT AT FL274. THE ASSIGNED ALT WAS FL280. I TOLD THE FO TO GET BACK TO FL280 AND HE IMMEDIATELY DID SO. A LOT WAS GOING ON, BUT I HAVE NO EXCUSE FOR THE DEV. THE FO AND I SPOKE ABOUT PAYING ATTN UNDER ALL CIRCUMSTANCES. I DO NOT THINK THIS TYPE OF PROB WILL OCCUR AGAIN. SUPPLEMENTAL INFO FROM ACN 441151: DURING SETUP OF HOLD, WE DSNDED THROUGH FL280, OUR LEVELING REQUIRED ALT. AT FL276, I TRIED TO RECOVER WITH AUTOPLT. AUTOPLT WAS SLOW TO RECOVER AT FL274. I TURNED OFF AUTOPLT AND MANUALLY RECOVERED AND CLBED BACK TO ASSIGNED FL280. CAUSE OF DEV WAS ATTRIBUTED TO HVY WORKLOAD, TSTM AVOIDANCE, HVY RADIO COM, 360 DEG DSNDING TURN FOLLOWED BY HOLDING INSTRUCTIONS, STRONG TURB, AND VFR INTO IMC.

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.