GLF3 crew had an altitude overshot in ZAU class a.

Attributes
ACN	513820
Time
Date	200105
Day	Fri
Place
Locale Reference	atc facility : zau.artcc
State Reference	IL
Altitude	msl bound lower : 21000 msl bound upper : 22000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : corporate
Make Model Name	Gulfstream III
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : corporate
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 70 flight time total : 9600 flight time type : 1500
ASRS Report	513820
Events
Anomaly	altitude deviation : overshoot non adherence : clearance non adherence : far non adherence : published procedure non adherence : company policies other anomaly other
Resolutory Action	controller : issued alert flight crew : returned to assigned altitude
Supplementary
Problem Areas	Flight Crew Human Performance Company
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Sic was flying the airplane from the left seat, ATC cleared us to climb to FL210. Aircraft was near FL220 when ATC asked our altitude. Our reply was we were going back to FL210. We feel 2 factors are in play in this aircraft: if you trim the autoplt to slow the rate of climb or descent within 10% of your leveloff altitude, the altitude preselect function of the autoplt turns off. The only warning is a small light that goes out. This airplane seems to have an intermittent altitude warning chime. If you are distraction and the chime fails to go off, you most likely will not see the altitude light.

Original NASA ASRS Text

Title: GLF3 CREW HAD AN ALT OVERSHOT IN ZAU CLASS A.

Narrative: SIC WAS FLYING THE AIRPLANE FROM THE LEFT SEAT, ATC CLRED US TO CLB TO FL210. ACFT WAS NEAR FL220 WHEN ATC ASKED OUR ALT. OUR REPLY WAS WE WERE GOING BACK TO FL210. WE FEEL 2 FACTORS ARE IN PLAY IN THIS ACFT: IF YOU TRIM THE AUTOPLT TO SLOW THE RATE OF CLB OR DSCNT WITHIN 10% OF YOUR LEVELOFF ALT, THE ALT PRESELECT FUNCTION OF THE AUTOPLT TURNS OFF. THE ONLY WARNING IS A SMALL LIGHT THAT GOES OUT. THIS AIRPLANE SEEMS TO HAVE AN INTERMITTENT ALT WARNING CHIME. IF YOU ARE DISTR AND THE CHIME FAILS TO GO OFF, YOU MOST LIKELY WILL NOT SEE THE ALT LIGHT.

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.