A B737 crew had similar call sign mix-up with company flight in ZDC class a airspace.

Attributes
ACN	516940
Time
Date	200106
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : zdc.artcc
State Reference	VA
Altitude	msl single value : 31000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zdc.artcc
Operator	common carrier : air carrier
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	cruise : enroute altitude change cruise : level
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zdc.artcc
Operator	common carrier : air carrier
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 215 flight time total : 7650 flight time type : 3150
ASRS Report	516940
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	non adherence : clearance non adherence : published procedure other anomaly other
Independent Detector	other flight crewa other flight crewb
Resolutory Action	controller : issued new clearance none taken : detected after the fact other
Supplementary
Problem Areas	Flight Crew Human Performance ATC Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

Another air carrier flight with similar call sign was navigating ahead of us on same center frequency. The other air carrier flight had answered for us at least twice. I had requested FL350, but was told it would be a few mins. I thought I heard a call for the similar sounding (ie, 1 number off) air carrier flight to climb to FL350. The other flight answered the call and center did not correct call sign. My first officer verified it was for the other flight. Then I heard center telling the other air carrier flight to remain at FL310! Our flight number was not called. A few mins later, I queried center just to ensure that we had not been the ones cleared to FL350 (eg, I said 'air carrier XXXX still at FL310, can we expect FL350 soon?' or something very close). Center then cleared us to climb to FL350. After thinking about this scenario, I could not be 100% sure if we had not missed the call taken by the other air carrier flight. If so, our climb to FL350 from FL310 was delayed by a few mins due to the confusion. When are we going to solve these types of human communication problems with some sort of data link/written communication? The human ear(south) is just too fallible!

Original NASA ASRS Text

Title: A B737 CREW HAD SIMILAR CALL SIGN MIX-UP WITH COMPANY FLT IN ZDC CLASS A AIRSPACE.

Narrative: ANOTHER ACR FLT WITH SIMILAR CALL SIGN WAS NAVING AHEAD OF US ON SAME CTR FREQ. THE OTHER ACR FLT HAD ANSWERED FOR US AT LEAST TWICE. I HAD REQUESTED FL350, BUT WAS TOLD IT WOULD BE A FEW MINS. I THOUGHT I HEARD A CALL FOR THE SIMILAR SOUNDING (IE, 1 NUMBER OFF) ACR FLT TO CLB TO FL350. THE OTHER FLT ANSWERED THE CALL AND CTR DID NOT CORRECT CALL SIGN. MY FO VERIFIED IT WAS FOR THE OTHER FLT. THEN I HEARD CTR TELLING THE OTHER ACR FLT TO REMAIN AT FL310! OUR FLT NUMBER WAS NOT CALLED. A FEW MINS LATER, I QUERIED CTR JUST TO ENSURE THAT WE HAD NOT BEEN THE ONES CLRED TO FL350 (EG, I SAID 'ACR XXXX STILL AT FL310, CAN WE EXPECT FL350 SOON?' OR SOMETHING VERY CLOSE). CTR THEN CLRED US TO CLB TO FL350. AFTER THINKING ABOUT THIS SCENARIO, I COULD NOT BE 100% SURE IF WE HAD NOT MISSED THE CALL TAKEN BY THE OTHER ACR FLT. IF SO, OUR CLB TO FL350 FROM FL310 WAS DELAYED BY A FEW MINS DUE TO THE CONFUSION. WHEN ARE WE GOING TO SOLVE THESE TYPES OF HUMAN COM PROBS WITH SOME SORT OF DATA LINK/WRITTEN COM? THE HUMAN EAR(S) IS JUST TOO FALLIBLE!

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.