FMC suddenly announces MAX FL 180, 747X goes crazy

[lensman 0]

Hi all,In brief, I'm flying along from Perth to Sydney FL310 with strong headwinds (25-50 kts) and all of a sudden the FMC announces MAX FL 180. There is no change in the MCP settings, or anything I can find in the FMC. The a/c, however, keeps pitching 10 degrees nose down and won't take no for an answer. I descend to FL210 and the rest of the flight is OK. Any ideas what the heck is going on? When I repeat the flight, the message appears at the same point every time. Thanks in advance, danFSX+Acceleration, PMDG 747X, ASUS P5K, Q9450@3.2GHz, 2GB RAM, 2TB disk, VisionTek Radeon 3850 512MB at 800 MHz/1200, Antek 900 case, 900W PSU, Saitek X52

[downscc 1,327]

This type of event could be due to switching focus (eg, looking at the FSX Map display) or due to weather abnormalities. It is interesting that it happens at the same location and is repeatable. I'd like to see a screen shot of this one.Rule out weather by using the clear sky selection (no weather).

[lensman 0]

Hi Dan,Will do. It may take a day or two to get the flight in. The first time, I definitely was switching views. The second and third times I was just waiting to see if it would go boom again. It's not overweight, but the rough winds are consistently there. Thanks,dan davison