Altitude deviation on descent. Reporter blames fatigue from poor rest scheduling.

Attributes
ACN	142887
Time
Date	199004
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : brd
State Reference	MN
Altitude	msl bound lower : 10400 msl bound upper : 12000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Light Transport, Low Wing, 2 Turboprop Eng
Flight Phase	descent other
Route In Use	arrival other enroute airway : zmp
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : commercial pilot : atp pilot : instrument
Experience	flight time last 90 days : 170 flight time total : 5000
ASRS Report	142887
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Experience	flight time last 90 days : 280 flight time total : 2010 flight time type : 610
Events
Anomaly	altitude deviation : overshoot
Independent Detector	other controllera other flight crewa
Resolutory Action	none taken : anomaly accepted
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Center assigned 12000'. Descended out of 17000' and continued descending to 10400' before captain (as PF) realized error. PNF (first officer) and PF both had eyes open but brain asleep. No traffic conflict. Far's rest and flight time daily limitations inadequate. Company does not view far's as maximum flight/minimum rest limitations, but as goals to aim for when developing schedule. Far's regarding altitude alert should be based on aircraft performance not on weight nor number of seats. Scheduled airline aircraft should have autoplts to reduce fatigue and provide stabilized approachs when pilots are fatigued. Require minimum comfort standard for pilot seats: including seat tilt, and lumbar adjustment (or at least convex seat curvature for the back instead of concave seat in the lumbar region).

Original NASA ASRS Text

Title: ALT DEVIATION ON DESCENT. REPORTER BLAMES FATIGUE FROM POOR REST SCHEDULING.

Narrative: CTR ASSIGNED 12000'. DSNDED OUT OF 17000' AND CONTINUED DSNDING TO 10400' BEFORE CAPT (AS PF) REALIZED ERROR. PNF (F/O) AND PF BOTH HAD EYES OPEN BUT BRAIN ASLEEP. NO TFC CONFLICT. FAR'S REST AND FLT TIME DAILY LIMITATIONS INADEQUATE. COMPANY DOES NOT VIEW FAR'S AS MAX FLT/MINIMUM REST LIMITATIONS, BUT AS GOALS TO AIM FOR WHEN DEVELOPING SCHEDULE. FAR'S REGARDING ALT ALERT SHOULD BE BASED ON ACFT PERFORMANCE NOT ON WT NOR NUMBER OF SEATS. SCHEDULED AIRLINE ACFT SHOULD HAVE AUTOPLTS TO REDUCE FATIGUE AND PROVIDE STABILIZED APCHS WHEN PLTS ARE FATIGUED. REQUIRE MINIMUM COMFORT STANDARD FOR PLT SEATS: INCLUDING SEAT TILT, AND LUMBAR ADJUSTMENT (OR AT LEAST CONVEX SEAT CURVATURE FOR THE BACK INSTEAD OF CONCAVE SEAT IN THE LUMBAR REGION).

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.