Some aircraft, including most jet transports, use an adjustable stabilizer to provide the required pitch trim forces.
<p>FAA
U.S. Department of Transportation
FEDERAL AVIATION ADMINISTRATION
</p>
Flight Standards Service
2016-01-01
<p><a rel="nofollow" class="external free" href="https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/phak/media/08_phak_ch6.pdf">https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/phak/media/08_phak_ch6.pdf</a>
</p>
Pilot’s Handbook of Aeronautical Knowledge