Glf-3 crew had an altitude deviation in ZDC class a airspace.

Attributes
ACN	572869
Time
Date	200302
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : swl.vortac
State Reference	MD
Altitude	msl bound lower : 24600 msl bound upper : 25000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zdc.artcc
Operator	general aviation : corporate
Make Model Name	Gulfstream III
Operating Under FAR Part	Part 91
Navigation In Use	other
Flight Phase	cruise : enroute altitude change
Flight Plan	IFR
Person 1
Affiliation	company : corporate
Function	flight crew : first officer oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 100 flight time total : 13600 flight time type : 2300
ASRS Report	572869
Person 2
Affiliation	company : corporate
Function	flight crew : captain
Events
Anomaly	altitude deviation : overshoot non adherence : far non adherence : clearance non adherence : published procedure other anomaly other
Independent Detector	atc equipment other atc equipment : radar other controllera
Resolutory Action	controller : issued alert flight crew : returned to assigned altitude other
Supplementary
Problem Areas	FAA Flight Crew Human Performance Company
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Flying with pilot not rated in aircraft, but current in beechjet and typed in beechjet and hawker. Previous flts had gone fine with copilot using autoplt correctly. Copilot was descending from altitude and I noticed as aircraft was approaching FL250 that aircraft had not begun leveloff. Sitting in right seat as PNF, I called out that the aircraft had not begun leveloff, quickly looked and noticed altitude intercept mode was not engaged. Copilot began (or so I thought) to manually level aircraft, but as I came to realize too late, only had hands on control column and was not making an input forceful enough to stop descent before dropping 400 ft below assigned altitude (FL246). Copilot quickly adjusted to FL250, but controller questioned altitude. Copilot noted that in aircraft he normally flies that aircraft will automatically level at altitude dialed in without manually selecting altitude intercept mode. My error was not taking control of aircraft immediately, but had copilot made correction when placing hands on wheel little or no altitude loss would have occurred.

Original NASA ASRS Text

Title: GLF-3 CREW HAD AN ALTDEV IN ZDC CLASS A AIRSPACE.

Narrative: FLYING WITH PLT NOT RATED IN ACFT, BUT CURRENT IN BEECHJET AND TYPED IN BEECHJET AND HAWKER. PREVIOUS FLTS HAD GONE FINE WITH COPLT USING AUTOPLT CORRECTLY. COPLT WAS DSNDING FROM ALT AND I NOTICED AS ACFT WAS APCHING FL250 THAT ACFT HAD NOT BEGUN LEVELOFF. SITTING IN R SEAT AS PNF, I CALLED OUT THAT THE ACFT HAD NOT BEGUN LEVELOFF, QUICKLY LOOKED AND NOTICED ALT INTERCEPT MODE WAS NOT ENGAGED. COPLT BEGAN (OR SO I THOUGHT) TO MANUALLY LEVEL ACFT, BUT AS I CAME TO REALIZE TOO LATE, ONLY HAD HANDS ON CTL COLUMN AND WAS NOT MAKING AN INPUT FORCEFUL ENOUGH TO STOP DSCNT BEFORE DROPPING 400 FT BELOW ASSIGNED ALT (FL246). COPLT QUICKLY ADJUSTED TO FL250, BUT CTLR QUESTIONED ALT. COPLT NOTED THAT IN ACFT HE NORMALLY FLIES THAT ACFT WILL AUTOMATICALLY LEVEL AT ALT DIALED IN WITHOUT MANUALLY SELECTING ALT INTERCEPT MODE. MY ERROR WAS NOT TAKING CTL OF ACFT IMMEDIATELY, BUT HAD COPLT MADE CORRECTION WHEN PLACING HANDS ON WHEEL LITTLE OR NO ALT LOSS WOULD HAVE OCCURRED.

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.