Flight crew has an altitude deviation while en route.

Attributes
ACN	717209
Time
Date	200611
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : zme.artcc
State Reference	TN
Altitude	msl bound lower : 38000 msl bound upper : 38700
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zme.artcc
Operator	general aviation : corporate
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 91
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : corporate
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 120 flight time total : 4900 flight time type : 490
ASRS Report	717209
Person 2
Affiliation	company : corporate
Function	flight crew : first officer
Events
Anomaly	altitude deviation : overshoot non adherence : clearance non adherence : far
Independent Detector	other controllera
Resolutory Action	controller : issued advisory flight crew : returned to assigned altitude
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Aircraft Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

At FL230 ATC cleared flight to FL380. Flight director and autoplt capture kicked off. Inadvertently; aircraft continued to climb slowly to FL387. ATC asked if leveled; and we returned to FL380. Crew was busy with rerte and next leg route. Both pilots assumed autoplt captured altitude hold. The navigation portion of autoplt configured correctly; and pitch axis controled the aircraft to FL387; at which ATC advised crew and promptly returned to FL380. Crew asked if conflict and ATC responded with no conflict and no problem. Result no pilot was monitoring aircraft or autoplt and assumed autoplt had control of aircraft. CRM was not in place at that time.

Original NASA ASRS Text

Title: FLT CREW HAS AN ALTDEV WHILE ENRTE.

Narrative: AT FL230 ATC CLRED FLT TO FL380. FLT DIRECTOR AND AUTOPLT CAPTURE KICKED OFF. INADVERTENTLY; ACFT CONTINUED TO CLB SLOWLY TO FL387. ATC ASKED IF LEVELED; AND WE RETURNED TO FL380. CREW WAS BUSY WITH RERTE AND NEXT LEG RTE. BOTH PLTS ASSUMED AUTOPLT CAPTURED ALT HOLD. THE NAV PORTION OF AUTOPLT CONFIGURED CORRECTLY; AND PITCH AXIS CTLED THE ACFT TO FL387; AT WHICH ATC ADVISED CREW AND PROMPTLY RETURNED TO FL380. CREW ASKED IF CONFLICT AND ATC RESPONDED WITH NO CONFLICT AND NO PROB. RESULT NO PLT WAS MONITORING ACFT OR AUTOPLT AND ASSUMED AUTOPLT HAD CTL OF ACFT. CRM WAS NOT IN PLACE AT THAT TIME.

Data retrieved from NASA's ASRS site as of January 2009 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.