Deviation from assigned altitude.

Attributes
ACN	139365
Time
Date	199003
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : zdc
State Reference	DC
Altitude	msl bound lower : 19000 msl bound upper : 22000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zdc tower : cak
Operator	general aviation : corporate
Make Model Name	Medium Transport
Navigation In Use	Other Other
Flight Phase	cruise other descent other
Route In Use	enroute other
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : cfi pilot : atp
Experience	flight time last 90 days : 50 flight time total : 13000 flight time type : 90
ASRS Report	139365
Person 2
Affiliation	Other
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : clearance other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : became reoriented flight crew : returned to intended course or assigned course
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation other

Narrative:

During the en route portion of our flight between st petersburg and washington dc, in the vicinity of richmond, we received what we believed to be a clearance for flight to descend to and maintain an altitude of 19000'. The first officer acknowledged the clearance and we initiated a descent. Shortly thereafter, we realized that ZDC was working another aircraft with a similar callsign. We asked for verification of our altitude and was informed that our assigned altitude was 22000' and to immediately climb to and maintain it. If center had informed us that another aircraft with a similar callsign was on the frequency, this incident could have been avoided.

Original NASA ASRS Text

Title: DEVIATION FROM ASSIGNED ALT.

Narrative: DURING THE ENRTE PORTION OF OUR FLT BTWN ST PETERSBURG AND WASHINGTON DC, IN THE VICINITY OF RICHMOND, WE RECEIVED WHAT WE BELIEVED TO BE A CLRNC FOR FLT TO DSND TO AND MAINTAIN AN ALT OF 19000'. THE F/O ACKNOWLEDGED THE CLRNC AND WE INITIATED A DSCNT. SHORTLY THEREAFTER, WE REALIZED THAT ZDC WAS WORKING ANOTHER ACFT WITH A SIMILAR CALLSIGN. WE ASKED FOR VERIFICATION OF OUR ALT AND WAS INFORMED THAT OUR ASSIGNED ALT WAS 22000' AND TO IMMEDIATELY CLB TO AND MAINTAIN IT. IF CENTER HAD INFORMED US THAT ANOTHER ACFT WITH A SIMILAR CALLSIGN WAS ON THE FREQ, THIS INCIDENT COULD HAVE BEEN AVOIDED.

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.