Took descent clearance meant for another aircraft.

Attributes
ACN	196903
Time
Date	199112
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : lmn
State Reference	IA
Altitude	msl bound lower : 13000 msl bound upper : 15000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zmp
Operator	common carrier : air carrier
Make Model Name	Light Transport, Low Wing, 2 Turboprop Eng
Flight Phase	cruise other descent other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 250 flight time total : 10500 flight time type : 300
ASRS Report	196903
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : clearance
Independent Detector	other controllera
Resolutory Action	other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I understood controller issue us a descent from 15000 to 11000. Instructed first officer (PNF) to request 7000 ft. ATC told us to standby. I then began descent to 11000 ft. Approximately 13000 ft ATC asked us if we had begun descent. First officer responded we were descending to 11000 as previously instructed. ATC informed us that descent instruction was for another company flight, whose flight number was the number we had used on our immediately preceding flight. Since that flight was on another frequency, we did not hear a response that would have clued us that it was not our instruction. I should have either waited for ATC to reinstruct us, or asked if the transmission was for us or not.

Original NASA ASRS Text

Title: TOOK DSCNT CLRNC MEANT FOR ANOTHER ACFT.

Narrative: I UNDERSTOOD CTLR ISSUE US A DSCNT FROM 15000 TO 11000. INSTRUCTED FO (PNF) TO REQUEST 7000 FT. ATC TOLD US TO STANDBY. I THEN BEGAN DSCNT TO 11000 FT. APPROX 13000 FT ATC ASKED US IF WE HAD BEGUN DSCNT. FO RESPONDED WE WERE DSNDING TO 11000 AS PREVIOUSLY INSTRUCTED. ATC INFORMED US THAT DSCNT INSTRUCTION WAS FOR ANOTHER COMPANY FLT, WHOSE FLT NUMBER WAS THE NUMBER WE HAD USED ON OUR IMMEDIATELY PRECEDING FLT. SINCE THAT FLT WAS ON ANOTHER FREQ, WE DID NOT HEAR A RESPONSE THAT WOULD HAVE CLUED US THAT IT WAS NOT OUR INSTRUCTION. I SHOULD HAVE EITHER WAITED FOR ATC TO REINSTRUCT US, OR ASKED IF THE XMISSION WAS FOR US OR NOT.

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.