Narrative:

Being vectored for visual approach amid intensely hectic traffic flow. Frequent ATC calls to watch for traffic. Radio chatter continuous. We were below a dissolving overcast in very hazy conditions, and it required concentrated effort to visually spot traffic. We were given a vector turn of 40 degrees, and traffic was called by ATC. Both the first officer and I were scanning outside for traffic, and I allowed the aircraft to descend about 400 ft before my altitude recovery was effective. ATC did not remark about deviation, and my recovery was rapid. Our airline does not consider autoplts cost effective and I allowed myself to be distracted by the traffic and lost focus on the altimeter. Both my first officer and I are tired. He was called late at night (awakened) and given an early morning report with 'reduced rest' and a later than scheduled departure. I have been flying trips all month that do not allow more than 6 1/2 hours of sleep per night. This scheduling is legal, and the law should be changed. This lifestyle is dangerous!

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Original NASA ASRS Text

Title: FLC OF AN FA22 DSNDED BELOW ASSIGNED ALT WHILE LOOKING FOR TFC. ALTDEV ALT EXCURSION.

Narrative: BEING VECTORED FOR VISUAL APCH AMID INTENSELY HECTIC TFC FLOW. FREQUENT ATC CALLS TO WATCH FOR TFC. RADIO CHATTER CONTINUOUS. WE WERE BELOW A DISSOLVING OVCST IN VERY HAZY CONDITIONS, AND IT REQUIRED CONCENTRATED EFFORT TO VISUALLY SPOT TFC. WE WERE GIVEN A VECTOR TURN OF 40 DEGS, AND TFC WAS CALLED BY ATC. BOTH THE FO AND I WERE SCANNING OUTSIDE FOR TFC, AND I ALLOWED THE ACFT TO DSND ABOUT 400 FT BEFORE MY ALT RECOVERY WAS EFFECTIVE. ATC DID NOT REMARK ABOUT DEV, AND MY RECOVERY WAS RAPID. OUR AIRLINE DOES NOT CONSIDER AUTOPLTS COST EFFECTIVE AND I ALLOWED MYSELF TO BE DISTRACTED BY THE TFC AND LOST FOCUS ON THE ALTIMETER. BOTH MY FO AND I ARE TIRED. HE WAS CALLED LATE AT NIGHT (AWAKENED) AND GIVEN AN EARLY MORNING RPT WITH 'REDUCED REST' AND A LATER THAN SCHEDULED DEP. I HAVE BEEN FLYING TRIPS ALL MONTH THAT DO NOT ALLOW MORE THAN 6 1/2 HRS OF SLEEP PER NIGHT. THIS SCHEDULING IS LEGAL, AND THE LAW SHOULD BE CHANGED. THIS LIFESTYLE IS DANGEROUS!

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.