Narrative:

A few seconds after I went to cabin interphone, center pointed out some traffic. We observed the traffic on the TCASII at about 10 O'clock position and 10 mi, a few hundred ft above us. A few seconds later, center cleared us to descend 300 ft. The first officer disengaged the autoplt and began the descent. Shortly thereafter center cleared us to climb back up to FL220. I heard the first officer acknowledge the clearance, and saw him turning the autoflt vertical speed wheel. I didn't remember that the autoplt was off. The descent continued at several hundred FPM. I verbally reminded the first officer to stop the descent. The first officer told me that he'd forgotten that the autoplt was off. We noticed another aircraft on the TCASII, the first officer halted the descent and started to climb, and we got a TCASII RA saying 'descend!' the first officer moved to increase the climb, and I said 'no, follow the RA!' he reversed the direction again and descended to follow the RA. Mode confusion -- hand flying versus autoplt. Some distraction wondering about the unusual clearance to descend 300 ft. Complacency -- no urgency, no need to do anything in a hurry!

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Original NASA ASRS Text

Title: A CANADAIR CL65 FLC WAS GIVEN A 300 FT DSCNT TO FL217 BY ZAU. THE FLC DSNDED THROUGH THE ASSIGNED ALT AND RECEIVED A TCASII RA NEAR PMM.

Narrative: A FEW SECONDS AFTER I WENT TO CABIN INTERPHONE, CTR POINTED OUT SOME TFC. WE OBSERVED THE TFC ON THE TCASII AT ABOUT 10 O'CLOCK POS AND 10 MI, A FEW HUNDRED FT ABOVE US. A FEW SECONDS LATER, CTR CLRED US TO DSND 300 FT. THE FO DISENGAGED THE AUTOPLT AND BEGAN THE DSCNT. SHORTLY THEREAFTER CTR CLRED US TO CLB BACK UP TO FL220. I HEARD THE FO ACKNOWLEDGE THE CLRNC, AND SAW HIM TURNING THE AUTOFLT VERT SPD WHEEL. I DIDN'T REMEMBER THAT THE AUTOPLT WAS OFF. THE DSCNT CONTINUED AT SEVERAL HUNDRED FPM. I VERBALLY REMINDED THE FO TO STOP THE DSCNT. THE FO TOLD ME THAT HE'D FORGOTTEN THAT THE AUTOPLT WAS OFF. WE NOTICED ANOTHER ACFT ON THE TCASII, THE FO HALTED THE DSCNT AND STARTED TO CLB, AND WE GOT A TCASII RA SAYING 'DSND!' THE FO MOVED TO INCREASE THE CLB, AND I SAID 'NO, FOLLOW THE RA!' HE REVERSED THE DIRECTION AGAIN AND DSNDED TO FOLLOW THE RA. MODE CONFUSION -- HAND FLYING VERSUS AUTOPLT. SOME DISTR WONDERING ABOUT THE UNUSUAL CLRNC TO DSND 300 FT. COMPLACENCY -- NO URGENCY, NO NEED TO DO ANYTHING IN A HURRY!

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.