B747 nose bounce when using flaps

Does anyone else has this problem in which the 747 bounces its nose uncontrollably when deploying the flaps?
So far, this is what I have:
Weight: 214379kg.
Flaps 0°
1°: 210kts.
5°: 190kts.
10°: 170kts.
20°: 150kts.
25°: 136kts.
30°: 130kts.

The problem begins with flaps 10, and increases when I further use the other flaps. This also happens on the 772ER, but its much more manageable.

Try using trim 100 degrees

Using autopilot right?

Yes. Leveled.

Maybe take it out of auto pilot when extending flaps, then when the craft is level re-engage AP

Um 100% trim would make it pitch up way to far.

What should I do?

I usually wait until it noses down on descent to increase flap angle. I have noticed a lot of nose bounce. If you deploy the to 15* you will go nose up very fast.

Yeah happens sometimes when I use autopilot as well. As the aircraft will naturally slowly pitch up when you extend the flaps, your -vs becomes a +Vs, so AP tries to correct and pitches the nose back down again…too much…so it corrects again back up…too much…back down…

I like to have control at that point anyway, so I get the aircraft in to position with AP and disengage it and come in manually.

How steep is your rate of decent?

I have the aircraft leveled. That´s how it should be when you´re in the pattern.

Try increasing the flaps at a lower speed but don’t let the plane stall and it should be fine

I never use trim, and have no problems. Probably just the AP adjusting to the sudden increase in lift. I haven’t experienced anything so dramatic, but might just need to apply flaps at slight slower speeds?


Yes I was saying not to use trim, someone suggested 100 trim to fix it. I think it happens if you arm flaps but are not descending.

What should I do with the 747? The 772ER doesn´t pitch so dramatically. Could it be the flight model?

Hmm, this never happens to me.

Does anyone have a solution?

You have to pull up to keep the nose from bouncing.

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But I descend with autopilot, isn´t it done like that in real life?

As many have said try increasing the flaps at a lower speed this should stop the increase in pitch. (For manual flight only)