Narrative:

While repositioning aircraft from maintenance hangar to terminal, area ground control was contacted. Ground control responded with statement 'radio is weak (and then unintelligible). Mechanic in r-hand seat was talking with ground -- thought controller said 'proceed.' 2 other aircraft were then cleared to taxi. These aircraft were behind us. While crossing active runway, ground control said 'why are there 3 aircraft taxiing on the taxiway?' I only cleared 2 aircraft, not 3.' we tried to contact ground control for an explanation but got no response. After shutdown, we talked with mechanics of the 2 aircraft, also dash 8's. They said they never heard us on the radio. Avionics troubleshoot of #2 communication found first officer's hand microphone to be inoperative or not clear enough to be heard. First officer's microphone was right&right'ed operations checked good. The fact that 3 aircraft of same type were taxiing from same location at the same time probably made the situation more confusing. The 2 aircraft behind us were cleared to taxi across all txwys and runways, while we in the lead aircraft were not. We weren't aware at the time that ground control couldn't hear the response of the lead aircraft when we responded to 'taxi as requested,' before we started. Ground control thought the last aircraft in line was the one in error, when in fact it was the first aircraft that had not responded on the radio.

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Original NASA ASRS Text

Title: WHILE REPOSITIONING ACFT, 2 MAINT TECHNICIANS TAXIED ACFT ONTO TXWY AND RWY WITHOUT CLRNC.

Narrative: WHILE REPOSITIONING ACFT FROM MAINT HANGAR TO TERMINAL, AREA GND CTL WAS CONTACTED. GND CTL RESPONDED WITH STATEMENT 'RADIO IS WEAK (AND THEN UNINTELLIGIBLE). MECH IN R-HAND SEAT WAS TALKING WITH GND -- THOUGHT CTLR SAID 'PROCEED.' 2 OTHER ACFT WERE THEN CLRED TO TAXI. THESE ACFT WERE BEHIND US. WHILE XING ACTIVE RWY, GND CTL SAID 'WHY ARE THERE 3 ACFT TAXIING ON THE TXWY?' I ONLY CLRED 2 ACFT, NOT 3.' WE TRIED TO CONTACT GND CTL FOR AN EXPLANATION BUT GOT NO RESPONSE. AFTER SHUTDOWN, WE TALKED WITH MECHS OF THE 2 ACFT, ALSO DASH 8'S. THEY SAID THEY NEVER HEARD US ON THE RADIO. AVIONICS TROUBLESHOOT OF #2 COM FOUND FO'S HAND MIKE TO BE INOP OR NOT CLR ENOUGH TO BE HEARD. FO'S MIKE WAS R&R'ED OPS CHKED GOOD. THE FACT THAT 3 ACFT OF SAME TYPE WERE TAXIING FROM SAME LOCATION AT THE SAME TIME PROBABLY MADE THE SIT MORE CONFUSING. THE 2 ACFT BEHIND US WERE CLRED TO TAXI ACROSS ALL TXWYS AND RWYS, WHILE WE IN THE LEAD ACFT WERE NOT. WE WEREN'T AWARE AT THE TIME THAT GND CTL COULDN'T HEAR THE RESPONSE OF THE LEAD ACFT WHEN WE RESPONDED TO 'TAXI AS REQUESTED,' BEFORE WE STARTED. GND CTL THOUGHT THE LAST ACFT IN LINE WAS THE ONE IN ERROR, WHEN IN FACT IT WAS THE FIRST ACFT THAT HAD NOT RESPONDED ON THE RADIO.

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.