Altitude deviation altitude overshot during descent.

Attributes
ACN	246103
Time
Date	199307
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : irw
State Reference	OK
Altitude	msl bound lower : 16500 msl bound upper : 17000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	descent other
Route In Use	enroute airway : zfw
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 180 flight time total : 5600 flight time type : 150
ASRS Report	246103
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 250 flight time total : 20000 flight time type : 1350
ASRS Report	245978
Events
Anomaly	altitude deviation : overshoot conflict : airborne less severe non adherence : clearance other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	flight crew : returned to intended course or assigned course flight crew : became reoriented
Consequence	Other
Miss Distance	horizontal : 18000 vertical : 500
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

While descending to 17000 ft in clear conditions. The captain (PF) and I were briefly distracted by an aircraft we saw on TCASII as well as visually. Through FL180 we both responded '1 to go.' we caught ourselves going approximately 500 ft low and returned to 17000 ft. We constantly switch from a model of the medium large transport with automatic level off to older models without it. This can cause confusion. I feel the fleet should be standardized in either confign. Also, the warning horn for altitude alert needs to tell us when we are about to bust an altitude, not that we have busted it. Supplemental information from acn it. Supplemental information from acn 245978: it's just a matter of time until all air carrier pilots do the same. Air carrier should standardize all autoplts! It would probably be cheaper than paying the feds!

Original NASA ASRS Text

Title: ALTDEV ALT OVERSHOT DURING DSCNT.

Narrative: WHILE DSNDING TO 17000 FT IN CLR CONDITIONS. THE CAPT (PF) AND I WERE BRIEFLY DISTRACTED BY AN ACFT WE SAW ON TCASII AS WELL AS VISUALLY. THROUGH FL180 WE BOTH RESPONDED '1 TO GO.' WE CAUGHT OURSELVES GOING APPROX 500 FT LOW AND RETURNED TO 17000 FT. WE CONSTANTLY SWITCH FROM A MODEL OF THE MLG WITH AUTO LEVEL OFF TO OLDER MODELS WITHOUT IT. THIS CAN CAUSE CONFUSION. I FEEL THE FLEET SHOULD BE STANDARDIZED IN EITHER CONFIGN. ALSO, THE WARNING HORN FOR ALT ALERT NEEDS TO TELL US WHEN WE ARE ABOUT TO BUST AN ALT, NOT THAT WE HAVE BUSTED IT. SUPPLEMENTAL INFO FROM ACN IT. SUPPLEMENTAL INFO FROM ACN 245978: IT'S JUST A MATTER OF TIME UNTIL ALL ACR PLTS DO THE SAME. ACR SHOULD STANDARDIZE ALL AUTOPLTS! IT WOULD PROBABLY BE CHEAPER THAN PAYING THE FEDS!

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.