The Beechcraft Model 18, or "Twin Beech", as it is better known, is a 6–11 seat, twin-engine, low-wing, conventional-gear aircraft that was manufactured by the Beech Aircraft Corporation of Wichita, Kansas. This model saw military service during and after World War II in a number of versions including the United States Army Air Forces (USAAF) C-45 Expeditor, AT-7 Navigator, AT-11 Kansan; and for the United States Navy (USN), UC-45J Navigator and the SNB-1 Kansan.
The Beech 18 has over 200 Federal Aviation Administration (FAA) approved Supplemental Type Certificates (STCs) available, each representing a modification to the original design.[citation needed]
In addition to carrying passengers the aircraft's uses have included aerial spraying, sterile insect release, fish seeding, dry ice cloud seeding, aerial firefighting, airborne mail pick up and drop, ambulance service, numerous movie productions, skydiving, freight, weapon- and drug-smuggling, engine test bed, skywriting and banner towing. Many are now in private hands.
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http://en.wikipedia.org/wiki/Beechcraft_Model_18On our side we will put so many images of this very important but forgoten airplane.