Narrative:

After leveling off at 8000 ft, the captain asked if I would like to set the power and lean the mixtures, in order to gain familiarity with the airplane. I began working with the power and mixture controls, and when I glanced at the flight instruments, we had climbed to 8400 ft. I immediately lowered the nose of the airplane and returned to 8000 ft. During the descent to 8000 ft, ATC remarked that our mode C indicated 8400 ft. Upon reflection, I think that we should have maintained crew coordination, with 1 pilot maintaining an instrument scan and positive control of the airplane, and the other pilot concentrating on adjusting the power. Alternatively, we could have set the autoplt to maintain heading and altitude, and then discussed the procedure for setting cruise power. Finally, considering the existing and forecast VMC, we could have carried out our training under VFR. Contributing factors would include the late hour, the fact that I had worked all day at another (non flying) job and was tired, and my lack of familiarity with the airplane. Also, the captain typically flies single-pilot, and is not accustomed to crew coordination, and does not have any company procedures for dividing duties between the flying and non-flying crew members. I was sitting in the right seat, and since there were no copilot instruments, I was in a more difficult position to keep the flight instruments in view while adjusting power.

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Original NASA ASRS Text

Title: PLT OF A CPR PIPER PA34, SENECA, WAS GIVEN ACFT CTL BY THE ASSIGNED PLT AND CLBED 400 FT WHILE ADJUSTING THE PWR AFTER LEVELOFF.

Narrative: AFTER LEVELING OFF AT 8000 FT, THE CAPT ASKED IF I WOULD LIKE TO SET THE PWR AND LEAN THE MIXTURES, IN ORDER TO GAIN FAMILIARITY WITH THE AIRPLANE. I BEGAN WORKING WITH THE PWR AND MIXTURE CTLS, AND WHEN I GLANCED AT THE FLT INSTS, WE HAD CLBED TO 8400 FT. I IMMEDIATELY LOWERED THE NOSE OF THE AIRPLANE AND RETURNED TO 8000 FT. DURING THE DSCNT TO 8000 FT, ATC REMARKED THAT OUR MODE C INDICATED 8400 FT. UPON REFLECTION, I THINK THAT WE SHOULD HAVE MAINTAINED CREW COORD, WITH 1 PLT MAINTAINING AN INST SCAN AND POSITIVE CTL OF THE AIRPLANE, AND THE OTHER PLT CONCENTRATING ON ADJUSTING THE PWR. ALTERNATIVELY, WE COULD HAVE SET THE AUTOPLT TO MAINTAIN HEADING AND ALT, AND THEN DISCUSSED THE PROC FOR SETTING CRUISE PWR. FINALLY, CONSIDERING THE EXISTING AND FORECAST VMC, WE COULD HAVE CARRIED OUT OUR TRAINING UNDER VFR. CONTRIBUTING FACTORS WOULD INCLUDE THE LATE HR, THE FACT THAT I HAD WORKED ALL DAY AT ANOTHER (NON FLYING) JOB AND WAS TIRED, AND MY LACK OF FAMILIARITY WITH THE AIRPLANE. ALSO, THE CAPT TYPICALLY FLIES SINGLE-PLT, AND IS NOT ACCUSTOMED TO CREW COORD, AND DOES NOT HAVE ANY COMPANY PROCS FOR DIVIDING DUTIES BTWN THE FLYING AND NON-FLYING CREW MEMBERS. I WAS SITTING IN THE R SEAT, AND SINCE THERE WERE NO COPLT INSTS, I WAS IN A MORE DIFFICULT POS TO KEEP THE FLT INSTS IN VIEW WHILE ADJUSTING PWR.

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.