Eh?744: Speedbrakes extend and then retract on landing !

[JSACKS 0]

I fly the 744 mostly in the VC nowadays and always arm speedbrakes on approach and observe that the handle is pulled back to "ARM." On T/down, the speedbrakes are deployed correctly, but sometimes momentarily, sometimes for slightly longer, and then they retract suddenly to the down position (i.e., flat) and stay there until I pull back the reversers and then the speedbrake panels lift up again.Why is this happening?Appreciate advice, info, or whatever, on this, thanks.Jonathan

[Qavion 19]

Your joystick throttle may not be completely at idle(?). The airplane logic may think you are initiating a go-around and has stowed the speedbrakes. Having said that, however, you should be able to deploy your reversers without the throttles being at idle. Anyway, make sure your indicated thrust as well as your joystick throttle is completely at idle at the moment of touchdown.Cheers.Q>

[JSACKS 0]

I see. So I think this is like the NG then? I did an autoland where the N1 fell from 68% on short final to around 45% on TD and maybe that was not a low enough N1 to get the speedbrakes to stay up?I shall monitor the throttle levers and thrust levels from now on more carefully. Thanks for posting.Jonathan

[Check_Airman 3]

Having said that, however, you>should be able to deploy your reversers without the throttles>being at idle.>>Cheers.>Q>shouldn't the word "NOT" be somewhere in that sentence?

[Qavion 19]

"shouldn't the word "NOT" be somewhere in that sentence?"oops.. too late to edit.Thanks!Q>