Narrative:

On jan/xa/01 while on climb out on air carrier flight #XXX from ZZZ to salt lake city, the right engine began to spool down to 78% N1 while the left engine remained at approximately 89% N1. The aircraft yawed and the autothrottles 'walked' back and forth. At cruise, the throttles remained split, about 1 knob width. During cruise, we sent a message to our maintenance controller via data link (ACARS) explaining the problem. We did not receive any response from maintenance. We sent another ACARS message to maintenance asking if they were aware of the problem. Again, we received no response. We then sent a message to dispatch explaining what had happened and to contact maintenance to see if they had received our messages. Dispatch replied over ACARS stating that maintenance knew of the situation. Upon our descent into slc with the throttles at idle, the master caution annunciator panel illuminated with an 'engine' light. The first officer and I looked on the overhead panel and saw the right power management control illuminated. While on descent, but above 10000 ft, the first officer sent another ACARS message to maintenance stating that we had a right power management control light. We landed and taxied to the gate to prepare for the flight to abc with an inoperative power management control. I (captain) received a new release and flight plan for the flight to abc. The flight plan reflected that the #2 power management control was inoperative and the MEL was revised, with the proper placard number. I called dispatch and asked for a 3-WAY patch to talk to the maintenance controller to discuss the situation. The dispatcher said that it was not necessary and that we had everything to depart to abc. We contacted maintenance via ACARS and maintenance then replied that we had departed slc with an open log item, and that the power management control was not deferred. We then replied to maintenance that we had the revised power management control inoperative flight plan and the placard number. After landing in abc, I called the maintenance controller over the phone about the situation. He stated that the log item concerning the power management control was still open and he asked some questions about the split throttle condition. The maintenance controller said that we had the legal paperwork since we had the revised power management control inoperative flight plan, weights and placard. Abc line maintenance inspected the right engine power management control, properly deferred the right engine power management control with maintenance concurrence, and revised the maintenance release document. The aircraft was then again operated that day with deferred power management control inoperative procedures. The cause of the problem was incomplete communication between the flight crew, maintenance controller and dispatch. This situation could have been prevented if all parties involved communicated together simultaneously via phone patch.

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Original NASA ASRS Text

Title: A B737-300 WAS DISPATCHED IN NON COMPLIANCE WITH AN OPEN LOGBOOK RPT CAUSED BY POOR COM BTWN THE CREW, DISPATCH AND MAINT.

Narrative: ON JAN/XA/01 WHILE ON CLBOUT ON ACR FLT #XXX FROM ZZZ TO SALT LAKE CITY, THE R ENG BEGAN TO SPOOL DOWN TO 78% N1 WHILE THE L ENG REMAINED AT APPROX 89% N1. THE ACFT YAWED AND THE AUTOTHROTTLES 'WALKED' BACK AND FORTH. AT CRUISE, THE THROTTLES REMAINED SPLIT, ABOUT 1 KNOB WIDTH. DURING CRUISE, WE SENT A MESSAGE TO OUR MAINT CTLR VIA DATA LINK (ACARS) EXPLAINING THE PROB. WE DID NOT RECEIVE ANY RESPONSE FROM MAINT. WE SENT ANOTHER ACARS MESSAGE TO MAINT ASKING IF THEY WERE AWARE OF THE PROB. AGAIN, WE RECEIVED NO RESPONSE. WE THEN SENT A MESSAGE TO DISPATCH EXPLAINING WHAT HAD HAPPENED AND TO CONTACT MAINT TO SEE IF THEY HAD RECEIVED OUR MESSAGES. DISPATCH REPLIED OVER ACARS STATING THAT MAINT KNEW OF THE SIT. UPON OUR DSCNT INTO SLC WITH THE THROTTLES AT IDLE, THE MASTER CAUTION ANNUNCIATOR PANEL ILLUMINATED WITH AN 'ENG' LIGHT. THE FO AND I LOOKED ON THE OVERHEAD PANEL AND SAW THE R PWR MGMNT CTL ILLUMINATED. WHILE ON DSCNT, BUT ABOVE 10000 FT, THE FO SENT ANOTHER ACARS MESSAGE TO MAINT STATING THAT WE HAD A R PWR MGMNT CTL LIGHT. WE LANDED AND TAXIED TO THE GATE TO PREPARE FOR THE FLT TO ABC WITH AN INOP PWR MGMNT CTL. I (CAPT) RECEIVED A NEW RELEASE AND FLT PLAN FOR THE FLT TO ABC. THE FLT PLAN REFLECTED THAT THE #2 PWR MGMNT CTL WAS INOP AND THE MEL WAS REVISED, WITH THE PROPER PLACARD NUMBER. I CALLED DISPATCH AND ASKED FOR A 3-WAY PATCH TO TALK TO THE MAINT CTLR TO DISCUSS THE SIT. THE DISPATCHER SAID THAT IT WAS NOT NECESSARY AND THAT WE HAD EVERYTHING TO DEPART TO ABC. WE CONTACTED MAINT VIA ACARS AND MAINT THEN REPLIED THAT WE HAD DEPARTED SLC WITH AN OPEN LOG ITEM, AND THAT THE PWR MGMNT CTL WAS NOT DEFERRED. WE THEN REPLIED TO MAINT THAT WE HAD THE REVISED PWR MGMNT CTL INOP FLT PLAN AND THE PLACARD NUMBER. AFTER LNDG IN ABC, I CALLED THE MAINT CTLR OVER THE PHONE ABOUT THE SIT. HE STATED THAT THE LOG ITEM CONCERNING THE PWR MGMNT CTL WAS STILL OPEN AND HE ASKED SOME QUESTIONS ABOUT THE SPLIT THROTTLE CONDITION. THE MAINT CTLR SAID THAT WE HAD THE LEGAL PAPERWORK SINCE WE HAD THE REVISED PWR MGMNT CTL INOP FLT PLAN, WTS AND PLACARD. ABC LINE MAINT INSPECTED THE R ENG PWR MGMNT CTL, PROPERLY DEFERRED THE R ENG PWR MGMNT CTL WITH MAINT CONCURRENCE, AND REVISED THE MAINT RELEASE DOCUMENT. THE ACFT WAS THEN AGAIN OPERATED THAT DAY WITH DEFERRED PWR MGMNT CTL INOP PROCS. THE CAUSE OF THE PROB WAS INCOMPLETE COM BTWN THE FLC, MAINT CTLR AND DISPATCH. THIS SIT COULD HAVE BEEN PREVENTED IF ALL PARTIES INVOLVED COMMUNICATED TOGETHER SIMULTANEOUSLY VIA PHONE PATCH.

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.