Approved Type Certificates

"Thumbs-Up From the Government"

An ATC, the Department of Commerce's Approval Type Certificate, was the principal goal for manufacturers after its introduction in the Air Commerce Act of 1926. This added substance, at least in the public mind, to an aircraft that had been awarded its own number—Uncle Sam had declared it airworthy, and safe for public use.

    It meant that the recipient had provided at least three aircraft for testing to meet or exceed government-established requirements, either under the eye of a DoC field representative or, in cases of large productions, substantiated by factory documents and affidavits.

Testing could be merciless. Wings were loaded with sandbags until the main spar cracked, aircraft were dropped from prescribed heights to prove the integrity of landing gears, strut fittings were wrenched until they fractured, and all other manners of torture were heaped upon an unfortunate sample as prescribed by the government. Often a shiny, new prototype would be reduced to kit form within hours.