Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Weight And Balance; Deviation / Discrepancy - Procedural MEL / CDL
Flight Crew Returned To Gate; Flight Crew Rejected Takeoff; General Flight Cancelled / Delayed; General Maintenance Action
Aircraft; MEL; Procedure
There was a [Deferred Maintenance Item] for the aircraft weight and balance system. During preflight; my FO (First Officer) noted that there was no expanded green band in the CG window. The FMC called for a stab trim setting of 3.6. It was in the green band; but very close to the edge of the green band in the CG window.During takeoff; sometime after 80 kts.; I saw the STAB CONFIG warning message; which I ignored. Shortly after that; I heard the Audible Warning; along with the Warning Light. I rejected. We stopped a long way from the end of the runway. We did not recall the speed at the time of the reject. Tower called us and asked if we needed assistance. We told him that we didn't; and that we were taxiing back to the blocks. After clearing the runway; we looked up the Brake Heating chart and estimated that we were in the Caution Zone. I taxied slowly; and used the brakes as little as practical. One wheel went up to a heat index of 5; and we got the BRAKE TEMP EICAS message and ran the checklist. During the taxi in; that wheel went down to a 4; and it was at a 3 when we blocked in.During taxi in; we noted that the FMC was now calling for a stab trim setting of 4.5. After blocking in; while talking to the Duty Pilot; I told him about the FMC stab trim change; from 3.6 during preflight; to 4.5 while taxiing in. He said that he had heard of this before. He asked us to run the performance again; and the FMC displayed a stab trim setting of 4.5.After blocking back in; I called the Dispatcher and told him that with my rest before the flight; the late hour of the flight; and my stress level after the reject; which I would be needing to go back to the hotel and rest before further duty. I ended up calling fatigued after we were done working with Maintenance on our aircraft anomaly.Fix the aircraft weight and balance system; instead of delaying the Maintenance item by putting it on a [Deferred Maintenance Item] status; or load the plane so it is not close to the edge of the CG range.
B747 Captain reported a rejected takeoff when the STAB CONFIG warning message appeared.