Flight crew of small transport excursioned from assigned altitude when they accepted a similar sound...

Attributes
ACN	139522
Time
Date	199003
Day	Wed
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : stl
State Reference	MO
Altitude	msl bound lower : 11000 msl bound upper : 11000
Environment
Flight Conditions	Mixed
Light	Night
Aircraft 1
Controlling Facilities	artcc : zkc
Operator	common carrier : air carrier
Make Model Name	Small Transport, Low Wing, 2 Turboprop Eng
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : instrument pilot : commercial pilot : cfi
Experience	flight time last 90 days : 220 flight time total : 2500 flight time type : 800
ASRS Report	139522
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : instrument pilot : atp 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 : returned to intended course or assigned course
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

There were 2 airplanes with the same airline and similar flight numbers being handled by the same controller. We took the other plane's climb clearance and read it back, so we started the climb. About 600' into the climb we reconfirmed the clearance and was told it was for the other plane. We descended back down with no further incident.

Original NASA ASRS Text

Title: FLT CREW OF SMT EXCURSIONED FROM ASSIGNED ALT WHEN THEY ACCEPTED A SIMILAR SOUNDING FLT CLRNC.

Narrative: THERE WERE 2 AIRPLANES WITH THE SAME AIRLINE AND SIMILAR FLT NUMBERS BEING HANDLED BY THE SAME CTLR. WE TOOK THE OTHER PLANE'S CLIMB CLRNC AND READ IT BACK, SO WE STARTED THE CLIMB. ABOUT 600' INTO THE CLIMB WE RECONFIRMED THE CLRNC AND WAS TOLD IT WAS FOR THE OTHER PLANE. WE DESCENDED BACK DOWN WITH NO FURTHER INCIDENT.

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.

Flight crew of small transport excursioned from assigned altitude when they accepted a similar sounding flight clearance.