Narrative:

As we approached the bff area we were picking up multiple thunderstorm cells on our WX radar screen. The captain asked me how I recommended proceeding through the area. I stated that if we stayed on our course we would be taking the best path. He pointed out the window at a buildup and asked me if I would be passing to the right or left of it. I wasn't sure which one he was pointing at. This discussion continued for approximately 30-40 seconds and as it went on, I became more frustrated since his question I felt was irrelevant to what we saw on the radar screen and trying to point out a cloud buildup from in the cockpit when there are many can be difficult. In my frustration I must have pulled back on the control yoke to slowly put us in a climb that neither of us noticed. When we finally were done with the discussion I look at the altimeter and we were approximately 300 ft above our assigned FL240. I immediately corrected and mentioned this to the captain. Our altitude alerters don't chime and flash until we are 300 ft high or low. We never heard or saw anything. What I feel caused the problem was that I allowed myself to become distraction and my scan suffered. To prevent, I will make sure my grip on the control yoke is light when my eyes are outside the cockpit and to maintain my scan.

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Original NASA ASRS Text

Title: PLT DEVIATES FROM ALT SLIGHTLY DURING FRUSTRATING DISCUSSION WITH HIS CAPT.

Narrative: AS WE APCHED THE BFF AREA WE WERE PICKING UP MULTIPLE TSTM CELLS ON OUR WX RADAR SCREEN. THE CAPT ASKED ME HOW I RECOMMENDED PROCEEDING THROUGH THE AREA. I STATED THAT IF WE STAYED ON OUR COURSE WE WOULD BE TAKING THE BEST PATH. HE POINTED OUT THE WINDOW AT A BUILDUP AND ASKED ME IF I WOULD BE PASSING TO THE R OR L OF IT. I WASN'T SURE WHICH ONE HE WAS POINTING AT. THIS DISCUSSION CONTINUED FOR APPROX 30-40 SECONDS AND AS IT WENT ON, I BECAME MORE FRUSTRATED SINCE HIS QUESTION I FELT WAS IRRELEVANT TO WHAT WE SAW ON THE RADAR SCREEN AND TRYING TO POINT OUT A CLOUD BUILDUP FROM IN THE COCKPIT WHEN THERE ARE MANY CAN BE DIFFICULT. IN MY FRUSTRATION I MUST HAVE PULLED BACK ON THE CTL YOKE TO SLOWLY PUT US IN A CLB THAT NEITHER OF US NOTICED. WHEN WE FINALLY WERE DONE WITH THE DISCUSSION I LOOK AT THE ALTIMETER AND WE WERE APPROX 300 FT ABOVE OUR ASSIGNED FL240. I IMMEDIATELY CORRECTED AND MENTIONED THIS TO THE CAPT. OUR ALT ALERTERS DON'T CHIME AND FLASH UNTIL WE ARE 300 FT HIGH OR LOW. WE NEVER HEARD OR SAW ANYTHING. WHAT I FEEL CAUSED THE PROB WAS THAT I ALLOWED MYSELF TO BECOME DISTR AND MY SCAN SUFFERED. TO PREVENT, I WILL MAKE SURE MY GRIP ON THE CTL YOKE IS LIGHT WHEN MY EYES ARE OUTSIDE THE COCKPIT AND TO MAINTAIN MY SCAN.

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.