The A1R Ryan ST-A Special is a two-seat, low wing monoplane. The fuselage is of monocoque-type construction employing longerons to reinforce the stressed skin at points of concentrated load – at stick control mountings, seats, floors, cockpit cutouts and at the tail section. Eight elliptical transverse bulkheads, suitably spaced, are covered with heavy gauge aluminium alloy skin.
The wings are constructed in four fabric covered sections – two stub wings and two outer panels. The outer panels are wire braced NACA airfoil, constructed of spruce spars, welded steel tube compression struts and aluminium alloy ribs. The stub wings are of welded steel tube construction, incorporating a walkway.
The landing gear is treadle type welded steel tube construction with shock absorber strut of oleo-spring type. The tail wheel is a steerable and full swiveling unit of welded steel tube construction, equipped with oleo shock strut.
ST-A Special airplane is equipped with Menasco-C4S 150 hp engine.
