Altitude deviation. Altitude overshot on descent.

Attributes
ACN	112958
Time
Date	198906
Day	Fri
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : iiu
State Reference	KY
Altitude	msl bound lower : 15750 msl bound upper : 16000
Environment
Flight Conditions	VMC
Light	Dusk
Aircraft 1
Controlling Facilities	artcc : zid tower : stl
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other
Flight Phase	descent other
Route In Use	arrival other enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : instrument pilot : flight engineer pilot : cfi pilot : atp
Experience	flight time last 90 days : 180 flight time total : 7000 flight time type : 30
ASRS Report	112958
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Events
Anomaly	altitude deviation : overshoot other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : returned to intended course or assigned course
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

While descending from FL240 to 16,000, ind ATC alerted us to crossing traffic at '2 O'clock at 14,000'. While looking for aircraft, we descended through 16,000' to 15,750' where I recovered back to 16,000'. ATC made no comment about the altitude deviation. I was not going to submit this report because I did not violate the +/- 300' buffer. But the same situation happened the next day. I felt 2 of these reports dealing with the same problem might get some action. I have notified my company of the problem. All other jet aircraft that I have flown have a visual and an audio alert at approximately 1000' before the altitude selected in the altitude alert window. I just checked out on medium large transport, first XXXX that I have flown. The medium large transport has only a visual (light) 750' before altitude selected. The light and the audio (chime) occurs 250' after the selected altitude has been passed, leaving only 50' before ATC alert! It would be nice to have the light, audio 750' prior to altitude selected.

Original NASA ASRS Text

Title: ALT DEVIATION. ALT OVERSHOT ON DESCENT.

Narrative: WHILE DESCENDING FROM FL240 TO 16,000, IND ATC ALERTED US TO XING TFC AT '2 O'CLOCK AT 14,000'. WHILE LOOKING FOR ACFT, WE DESCENDED THROUGH 16,000' TO 15,750' WHERE I RECOVERED BACK TO 16,000'. ATC MADE NO COMMENT ABOUT THE ALT DEVIATION. I WAS NOT GOING TO SUBMIT THIS REPORT BECAUSE I DID NOT VIOLATE THE +/- 300' BUFFER. BUT THE SAME SITUATION HAPPENED THE NEXT DAY. I FELT 2 OF THESE REPORTS DEALING WITH THE SAME PROBLEM MIGHT GET SOME ACTION. I HAVE NOTIFIED MY COMPANY OF THE PROBLEM. ALL OTHER JET ACFT THAT I HAVE FLOWN HAVE A VISUAL AND AN AUDIO ALERT AT APPROX 1000' BEFORE THE ALT SELECTED IN THE ALT ALERT WINDOW. I JUST CHECKED OUT ON MLG, FIRST XXXX THAT I HAVE FLOWN. THE MLG HAS ONLY A VISUAL (LIGHT) 750' BEFORE ALT SELECTED. THE LIGHT AND THE AUDIO (CHIME) OCCURS 250' AFTER THE SELECTED ALT HAS BEEN PASSED, LEAVING ONLY 50' BEFORE ATC ALERT! IT WOULD BE NICE TO HAVE THE LIGHT, AUDIO 750' PRIOR TO ALT SELECTED.

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.