Altitude deviation. Crossing restriction not met on visual approach utilizing ILS.

Attributes
ACN	113311
Time
Date	198906
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : dfw
State Reference	TX
Altitude	msl bound lower : 2600 msl bound upper : 3000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : dfw
Operator	common carrier : air carrier
Make Model Name	Light Transport, Low Wing, 2 Turboprop Eng
Navigation In Use	Other
Flight Phase	descent : approach
Route In Use	arrival other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 250 flight time total : 5000 flight time type : 300
ASRS Report	113311
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	altitude deviation : overshoot altitude deviation : crossing restriction not met non adherence : clearance other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : became reoriented other
Consequence	Other
Supplementary
Primary Problem	Ambiguous
Air Traffic Incident	Pilot Deviation

Narrative:

During visual approach to runway 31R, cleared for visual approach, maintain 3000 until vande. Captain descending out of 4000' on the localizer. All parameters of approach normal. I was watching out right side window for traffic from nearby dal airport. When I returned to instrument scan aircraft was 2600' descending, 1 mi from vande. I advised captain of deviation, restating altitude restriction. Captain continued visual approach for normal landing. Approach handoff to tower per normal operation. This occurred at end of 13 hour duty day on last day of 4 day trip. Rest was reduced on previous night to 8 hours + 20 min. Resulting sleep period reduced to approximately 6 hours. Suggest that with a reasonable amount of sleep and a reasonable length of duty time crew alertness could be better maintained. It is unfortunate that many airlines push flight crews to the absolute minimum rest required by far's on an ongoing basis. I believe this violates the intent of rest requirements and sets the stage for what could be a disastrous situation.

Original NASA ASRS Text

Title: ALT DEVIATION. CROSSING RESTRICTION NOT MET ON VISUAL APCH UTILIZING ILS.

Narrative: DURING VISUAL APCH TO RWY 31R, CLRED FOR VISUAL APCH, MAINTAIN 3000 UNTIL VANDE. CAPT DESCENDING OUT OF 4000' ON THE LOC. ALL PARAMETERS OF APCH NORMAL. I WAS WATCHING OUT RIGHT SIDE WINDOW FOR TFC FROM NEARBY DAL ARPT. WHEN I RETURNED TO INSTRUMENT SCAN ACFT WAS 2600' DESCENDING, 1 MI FROM VANDE. I ADVISED CAPT OF DEVIATION, RESTATING ALT RESTRICTION. CAPT CONTINUED VISUAL APCH FOR NORMAL LNDG. APCH HANDOFF TO TWR PER NORMAL OPERATION. THIS OCCURRED AT END OF 13 HOUR DUTY DAY ON LAST DAY OF 4 DAY TRIP. REST WAS REDUCED ON PREVIOUS NIGHT TO 8 HRS + 20 MIN. RESULTING SLEEP PERIOD REDUCED TO APPROX 6 HRS. SUGGEST THAT WITH A REASONABLE AMOUNT OF SLEEP AND A REASONABLE LENGTH OF DUTY TIME CREW ALERTNESS COULD BE BETTER MAINTAINED. IT IS UNFORTUNATE THAT MANY AIRLINES PUSH FLT CREWS TO THE ABSOLUTE MINIMUM REST REQUIRED BY FAR'S ON AN ONGOING BASIS. I BELIEVE THIS VIOLATES THE INTENT OF REST REQUIREMENTS AND SETS THE STAGE FOR WHAT COULD BE A DISASTROUS SITUATION.

Data retrieved from NASA's ASRS site as of August 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.