DC9 flight crew descends below assigned altitude during descent.

Attributes
ACN	329150
Time
Date	199602
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : jvl
State Reference	WI
Altitude	msl bound lower : 26700 msl bound upper : 33000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zau
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	descent other
Route In Use	enroute : direct
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : cfi pilot : atp
Experience	flight time last 90 days : 210 flight time total : 25000
ASRS Report	329150
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	altitude deviation : overshoot
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance flight crew : returned to intended course or assigned course
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Started descent from FL330 to FL270 with full (heavy) aircraft to 100 plus KT tailwind. I found I needed a high rate of descent (6000+ FPM). Started leveloff at +2000 ft but rotated the autoplt descent control a little too slow. Selected level flight by FL270 but aircraft continued for about 300 ft hesitated 2 seconds before starting up. Then ATC cleared us to FL240. Possible factors: heavy aircraft, unusually heavy. Approximately 120 KT tailwind. My scan and xchk left out a glance at the autoplt rate of descent knob during the leveloff to let me know how much I had to rotate it versus rate of descent and altitude left. Contributing factors: lack of sleep and some distraction due to a potential divorce action. I discussed these factors with the first officer at our first private opportunity. No private time was available before takeoff due to others in cockpit, including a jump seat rider.

Original NASA ASRS Text

Title: DC9 FLC DSNDS BELOW ASSIGNED ALT DURING DSCNT.

Narrative: STARTED DSCNT FROM FL330 TO FL270 WITH FULL (HVY) ACFT TO 100 PLUS KT TAILWIND. I FOUND I NEEDED A HIGH RATE OF DSCNT (6000+ FPM). STARTED LEVELOFF AT +2000 FT BUT ROTATED THE AUTOPLT DSCNT CTL A LITTLE TOO SLOW. SELECTED LEVEL FLT BY FL270 BUT ACFT CONTINUED FOR ABOUT 300 FT HESITATED 2 SECONDS BEFORE STARTING UP. THEN ATC CLRED US TO FL240. POSSIBLE FACTORS: HVY ACFT, UNUSUALLY HVY. APPROX 120 KT TAILWIND. MY SCAN AND XCHK LEFT OUT A GLANCE AT THE AUTOPLT RATE OF DSCNT KNOB DURING THE LEVELOFF TO LET ME KNOW HOW MUCH I HAD TO ROTATE IT VERSUS RATE OF DSCNT AND ALT LEFT. CONTRIBUTING FACTORS: LACK OF SLEEP AND SOME DISTR DUE TO A POTENTIAL DIVORCE ACTION. I DISCUSSED THESE FACTORS WITH THE FO AT OUR FIRST PVT OPPORTUNITY. NO PVT TIME WAS AVAILABLE BEFORE TKOF DUE TO OTHERS IN COCKPIT, INCLUDING A JUMP SEAT RIDER.

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.