Ryan Aeronautical ST3

The airframe is aluminium: sheet metal over a riveted frame, the way most aircraft have been built since the 1940s. The Ryan ST: an aluminium fuselage with fabric-covered wings. The design is held under 1 type certificate (A-749, held by Ryan Aeronautical Company). The FAA has issued 2 airworthiness directives (orders that owners must comply with) that name this model, most of them about airframe structure. Operators and repair shops have filed 2 failure reports with the FAA since 2001, 2 of them in the last ten years: about 0.9 a year for every 100 aircraft on the register; the system most often named is cabin, seats and restraints. 30 approved modifications exist for it, the most by Helicorp INC..

Sources: the FAA's type certificate data sheets, airworthiness directives, supplemental type certificates, special conditions and special airworthiness information bulletins (Dynamic Regulatory System), and the FAA's service difficulty reports. A failure report is what an operator or repair station chose to file; the counts show reporting as much as reliability, and larger and commercial fleets report more. How the systems are grouped.