ATA 27-45, Horizontal Stabilizer Position

Inbound write-up of Stabilizer in Motion Warning, Incorrect Stabilizer Position Indication, and Stall Warnings.

The "first place we should of gone was Flight Fault History..... we never actually did. Instead we went straight for the stabilizer position LVDT's which could be read from their corresponding FCC computer's "sensors" page..

While watching each LVDT position output, we drove the stabilizer full travel. They "seemed" to match, but the #2 was lagging and jumpy. With the stab at rest, the #2 never did settle down.

We didn't have one in stock, but an inspection and plug cleaning "would" of been helpful. Problem is..... we couldn't get to it.

The LVDT is driven by a rod from the aft pivot point of the stabilizer.



It goes through a hole (in what appears to be) the APU box.



View from the forward stabilizer access hole.




I saw no way to get to the damn thing. We used (a somewhat) iffy MEL and dispatched the aircraft. The LVDT was changed in Memphis and did not repeat, but I'd still like to know where/how to get to it.




MD-11 ASM 27-45-0
AMM 27-45-01-4

Link to a LVDT Tutorial