Narrative:

We were departing dca to cvg. We were cleared up to FL200. The aircraft we were flying had an autoplt that did not have altitude capture. We were at ldn VOR and with station passage came a task saturation point. We were adjusting for the outbound radial as well as adjusting the WX radar to get the best route to request to deviate around cumulo nimbus that were up to 40000 ft. In the confusion of all this and the related discussion on our best course of action, we caught ourselves at 20200 ft and began to nose it over as ATC called us to confirm we were leveling. Our altitude peaked at 20400 ft and ATC called out traffic in our area but I can't remember what the distance was. No alerts or evasive action (other than descending to FL200) were taken.

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Original NASA ASRS Text

Title: A B727 CREW OVERSHOOTS THEIR ASSIGNED ALT WHILE DISTRACTED BY WX DEV PLANNING. AN AUTOPLT WITHOUT AUTO LEVELING CAPABILITY WAS IN USE.

Narrative: WE WERE DEPARTING DCA TO CVG. WE WERE CLRED UP TO FL200. THE ACFT WE WERE FLYING HAD AN AUTOPLT THAT DID NOT HAVE ALT CAPTURE. WE WERE AT LDN VOR AND WITH STATION PASSAGE CAME A TASK SATURATION POINT. WE WERE ADJUSTING FOR THE OUTBOUND RADIAL AS WELL AS ADJUSTING THE WX RADAR TO GET THE BEST RTE TO REQUEST TO DEVIATE AROUND CUMULO NIMBUS THAT WERE UP TO 40000 FT. IN THE CONFUSION OF ALL THIS AND THE RELATED DISCUSSION ON OUR BEST COURSE OF ACTION, WE CAUGHT OURSELVES AT 20200 FT AND BEGAN TO NOSE IT OVER AS ATC CALLED US TO CONFIRM WE WERE LEVELING. OUR ALT PEAKED AT 20400 FT AND ATC CALLED OUT TFC IN OUR AREA BUT I CAN'T REMEMBER WHAT THE DISTANCE WAS. NO ALERTS OR EVASIVE ACTION (OTHER THAN DSNDING TO FL200) WERE TAKEN.

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.