This is an updated version of the the tail assembly from my Lockheed C-5 Galaxy. It features fully-trimming horizontal stabilizers controlled by AG6 and the trim slider, a feature I forgot to add to the original. Set it to your desired trim, then lock it when on the ground. Or use it in the air for more aggressive trim. The C-5 will now auto-takeoff with full nose-up trim, and I've tested it for level flight with dead-weight up to 800,000 lbs.

Installation instructions:
(1) Remove the cockpit and save the entire unit as a subassembly.
(2) Open the C-5.
(3) Grab the tail at the fuselage block just above the rudder, and discard it with the rest of the assembly.
(4) Load the new subassembly, and attach it to the fuselage portion of the vertical stabilizer, being careful to properly align the leading edges of the two parts.
(5) Perform an operational test to ensure the mechanism works.
(6) Overwrite the original file.