Originally Posted by
Grebe
Curious to know how many reports of a lube problem with the Boeing used ball-jackscrew system ?
The fact that some crews are struggling to turn the trim wheel in some situations can be classed as partly a lube problem because some of the effort that they are putting into turning the jackscrew is being lost in overcoming frictional forces caused by less than perfect lubrication.Probably not a great deal but it is some, and if I were a Boeing engineer faced with the possibility of having to retrofit 7,500 new servo motors and clutches I would be looking at every possible way to make the existing manual trim system more efficient.