The U.S. aircraft register, updated daily
Who holds what · as the FAA records the name

Tri-State Aviation, INC

Holds 3 approved modifications, most of them for the Ayres Corporation S-2. FAA spelling: Tri-State Aviation, Inc.

Approved modifications 3 · newest first

Ayres Corporation S-2 1Cessna 188 1Cessna A188 1Cessna T188 1
2014-12-31SA3239CH · Installation of modified propeller blades · Army P-51C, Army P-51D, Army P-51K
1991-10-24SA1653GL · Install Aileron Servo Tabs. · S2R
1991-08-06SA586GL · Installation of spray boom system. (T188C RESTRICTED CATEGORY) · A188B, A188A, A188

Source: FAA Dynamic Regulatory System (type certificate data sheets, supplemental type certificates, technical standard order authorisations). An organisation's name is as the FAA spelled it on each record; related spellings are separate pages.