Narrative:

At FL310, top of descent, copilot's leg, flight rdu-cvg cleared direct dresr to cross it at FL240. I called out of FL310, saw copilot set up FMS and autoplt for descent. At same time, flight attendant called to offer breakfast. As he brought food forward, ZID asked our altitude and if we would make the restr at dresr. I looked up at the altimeters. We were still at FL310. I put aircraft into rapid descent (IAS mode, .80 mach, idle, speed brakes). When we were 2 mi from dresr at FL260, descending at over 6000 FPM, controller gave us a 90 degree turn to right. We turned less than 30 degrees before he cleared direct to our next navigation point. I checked TCASII. There was not another aircraft for 20 mi. I do not believe there was a loss of separation. If there is a lesson learned for me, this aircraft's automation has certain pitfalls that I must be specially aware of. Also, when I am the PNF, I need to check what the PF is doing, religiously, and learn to filter out distrs. Supplemental information from acn 414123: began descent via VNAV path, captain called out of FL310. Aircraft intercepted and began descent. At this time flight attendant knocked on door to offer breakfast. Shortly after this, center asked our altitude. We checked and aircraft was back at FL310 in VNAV level. The aircraft had descended 300 ft initially, but at some time during this period must have returned to VNAV level unnoticed by myself or the captain. We leveled at FL240 over dresr and proceeded with continuation of arrival/approach. Crossing altitude would have been made, but we had reported out of FL310 earlier and were still level and were unsure at time if we would make altitude restr.

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Original NASA ASRS Text

Title: AN MD88 FLC DOES NOT START DOWN AFTER RECEIVING THEIR DSCNT CLRNC. THE CREW WAS INTERRUPTED BY THE FLT ATTENDANT AND THE CTR CTLR HAD TO ASK THE CREW ABOUT THEIR ALT.

Narrative: AT FL310, TOP OF DSCNT, COPLT'S LEG, FLT RDU-CVG CLRED DIRECT DRESR TO CROSS IT AT FL240. I CALLED OUT OF FL310, SAW COPLT SET UP FMS AND AUTOPLT FOR DSCNT. AT SAME TIME, FLT ATTENDANT CALLED TO OFFER BREAKFAST. AS HE BROUGHT FOOD FORWARD, ZID ASKED OUR ALT AND IF WE WOULD MAKE THE RESTR AT DRESR. I LOOKED UP AT THE ALTIMETERS. WE WERE STILL AT FL310. I PUT ACFT INTO RAPID DSCNT (IAS MODE, .80 MACH, IDLE, SPD BRAKES). WHEN WE WERE 2 MI FROM DRESR AT FL260, DSNDING AT OVER 6000 FPM, CTLR GAVE US A 90 DEG TURN TO R. WE TURNED LESS THAN 30 DEGS BEFORE HE CLRED DIRECT TO OUR NEXT NAV POINT. I CHKED TCASII. THERE WAS NOT ANOTHER ACFT FOR 20 MI. I DO NOT BELIEVE THERE WAS A LOSS OF SEPARATION. IF THERE IS A LESSON LEARNED FOR ME, THIS ACFT'S AUTOMATION HAS CERTAIN PITFALLS THAT I MUST BE SPECIALLY AWARE OF. ALSO, WHEN I AM THE PNF, I NEED TO CHK WHAT THE PF IS DOING, RELIGIOUSLY, AND LEARN TO FILTER OUT DISTRS. SUPPLEMENTAL INFO FROM ACN 414123: BEGAN DSCNT VIA VNAV PATH, CAPT CALLED OUT OF FL310. ACFT INTERCEPTED AND BEGAN DSCNT. AT THIS TIME FLT ATTENDANT KNOCKED ON DOOR TO OFFER BREAKFAST. SHORTLY AFTER THIS, CTR ASKED OUR ALT. WE CHKED AND ACFT WAS BACK AT FL310 IN VNAV LEVEL. THE ACFT HAD DSNDED 300 FT INITIALLY, BUT AT SOME TIME DURING THIS PERIOD MUST HAVE RETURNED TO VNAV LEVEL UNNOTICED BY MYSELF OR THE CAPT. WE LEVELED AT FL240 OVER DRESR AND PROCEEDED WITH CONTINUATION OF ARR/APCH. XING ALT WOULD HAVE BEEN MADE, BUT WE HAD RPTED OUT OF FL310 EARLIER AND WERE STILL LEVEL AND WERE UNSURE AT TIME IF WE WOULD MAKE ALT RESTR.

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.