Narrative:

Our encoding altimeter was deferred. Our dispatcher assured us that he had contacted ATC and obtained approval for our flight with encoder off, per our MEL. Upon initial contact with tpa departure, they commented about our lack of altitude readout. We told departure that our dispatcher had cleared our encoder off flight with miami and ZJX. Shortly later, departure came back saying that neither him nor the next ZJX controller had been notified of our condition. We were treated to a lecture on TCA operations. We don't think that a traffic conflict existed at any time. Remainder of our flight was normal except for occasional altitude callout request. Post-flight discussion with dispatcher revealed that he'd actually spoken to mia, jax, and ind ctrs with their ok, with mia center originally assuring dispatcher that he'd pass it along. He didn't recall exactly who in ATC he spoke to, but it evidently was not passed through the chain. Although I had assurance that our encoder off flight was approved by ATC, I should have checked with tpa by radio or local phone call that they had the word passed on to them with no 'surprises.'

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Original NASA ASRS Text

Title: DISPATCHER GETS OK FROM CTR FOR FLT TO DEPART WITH ENCODER INOP. DEP CTLR NOT AWARE, LECTURES FLC.

Narrative: OUR ENCODING ALTIMETER WAS DEFERRED. OUR DISPATCHER ASSURED US THAT HE HAD CONTACTED ATC AND OBTAINED APPROVAL FOR OUR FLT WITH ENCODER OFF, PER OUR MEL. UPON INITIAL CONTACT WITH TPA DEP, THEY COMMENTED ABOUT OUR LACK OF ALT READOUT. WE TOLD DEP THAT OUR DISPATCHER HAD CLRED OUR ENCODER OFF FLT WITH MIAMI AND ZJX. SHORTLY LATER, DEP CAME BACK SAYING THAT NEITHER HIM NOR THE NEXT ZJX CTLR HAD BEEN NOTIFIED OF OUR CONDITION. WE WERE TREATED TO A LECTURE ON TCA OPS. WE DON'T THINK THAT A TFC CONFLICT EXISTED AT ANY TIME. REMAINDER OF OUR FLT WAS NORMAL EXCEPT FOR OCCASIONAL ALT CALLOUT REQUEST. POST-FLT DISCUSSION WITH DISPATCHER REVEALED THAT HE'D ACTUALLY SPOKEN TO MIA, JAX, AND IND CTRS WITH THEIR OK, WITH MIA CTR ORIGINALLY ASSURING DISPATCHER THAT HE'D PASS IT ALONG. HE DIDN'T RECALL EXACTLY WHO IN ATC HE SPOKE TO, BUT IT EVIDENTLY WAS NOT PASSED THROUGH THE CHAIN. ALTHOUGH I HAD ASSURANCE THAT OUR ENCODER OFF FLT WAS APPROVED BY ATC, I SHOULD HAVE CHKED WITH TPA BY RADIO OR LCL PHONE CALL THAT THEY HAD THE WORD PASSED ON TO THEM WITH NO 'SURPRISES.'

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.