An airworthiness certificate is a document delivered to the registered owner of an aircraft certifying that it meets or exceeds the FAA safety standards. With it, the airplane’s owner is authorized to operate the aircraft.
The standards in an airworthiness inspection vary between aircraft, and are specific to that particular manufacturer, model, year, etc. These inspections are done and will only be recognized as valid if done by an FAA Aviation Safety Inspector and/or an authorized Representative of the Administrator, as defined in 14 CFR Part 183. These certificates can be revoked by the FAA at any time if the aircraft no longer meets those safety standards or has strayed too far from its approved design.
There are two different classifications of FAA airworthiness certificates, a Standard Airworthiness Certificate and a Special Airworthiness Certificate. The determination of which certificate is required depends upon the classification of aircraft being registering. Normal, Utility, Acrobatic, Commuter, Transport, Manned free balloons and special classes aircraft fall under a Standard Airworthiness Certificate.
A Special Airworthiness Certificate from the FAA allows an operator to operate an aircraft in one or more of the following categories: Primary, Restricted, Multiple, Limited, Light-Sport, Experimental, Special Flight Permit or Provisional.