2 air carrier flts with similar call signs causes confusion for flight crews and controllers.

Attributes
ACN	134759
Time
Date	199001
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : fll
State Reference	FL
Altitude	msl bound lower : 9000 msl bound upper : 18000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zma
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 250 flight time total : 7100 flight time type : 1200
ASRS Report	134759
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	other anomaly other
Independent Detector	other flight crewa
Resolutory Action	other
Consequence	Other
Supplementary
Primary Problem	Ambiguous
Air Traffic Incident	other

Narrative:

Our flight was xyz when we departed fll airport. We were turned over from departure to ZMA. We were given numerous altitudes and radar vectors to avoid a military restr area. The controller called a flight xyp. There was no response, then I replied asking if he had meant flight xyz. We weren't sure of his reply, but we read back his instruction and received no reply. After a few mins he switched us to a new frequency. When we switched over we heard a company aircraft with xyp as the flight #. Similarity in flight #'south could possibly cause serious problems in the ATC system. As a crew we need to listen up for the appropriate flight #.

Original NASA ASRS Text

Title: 2 ACR FLTS WITH SIMILAR CALL SIGNS CAUSES CONFUSION FOR FLT CREWS AND CTLRS.

Narrative: OUR FLT WAS XYZ WHEN WE DEPARTED FLL ARPT. WE WERE TURNED OVER FROM DEP TO ZMA. WE WERE GIVEN NUMEROUS ALTS AND RADAR VECTORS TO AVOID A MIL RESTR AREA. THE CTLR CALLED A FLT XYP. THERE WAS NO RESPONSE, THEN I REPLIED ASKING IF HE HAD MEANT FLT XYZ. WE WEREN'T SURE OF HIS REPLY, BUT WE READ BACK HIS INSTRUCTION AND RECEIVED NO REPLY. AFTER A FEW MINS HE SWITCHED US TO A NEW FREQ. WHEN WE SWITCHED OVER WE HEARD A COMPANY ACFT WITH XYP AS THE FLT #. SIMILARITY IN FLT #'S COULD POSSIBLY CAUSE SERIOUS PROBS IN THE ATC SYS. AS A CREW WE NEED TO LISTEN UP FOR THE APPROPRIATE FLT #.

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.