P.S. I assume you're not using any automation at all when you're experiencing this problem? You'll recall in the manual that when in take-off mode Mr. Lockheed offers some sort of weird "trim assisted" automation to get to and hold the proper pitch up that took me awhile to get used to. No load imbalances or anything? Setting your TO trim? Paul's Gauge is a good free addon that will give you values for that plus other good stuff.