The design was by Dipl-Ing
Klaus Holighaus and the prototype first flew in May 1974. The production examples incorporated several improvements in January 1975. The Janus has a glass-fibre monocoque fuselage similar to that of the
Nimbus-2 but the cockpit section is lengthened to accommodate the two pilots in tandem with dual controls under a right-hand side-hinged one-piece
canopy. Landing gear consists of either a non-retractable main wheel (Janus A, B & C) or a retractable main wheel (later models of Janus C and all Ce's) with a drum or disc brake, and a nose-wheel. The two-piece wings have 2° forward sweep on the leading edge, and have camber-changing
flaps which are operated between +12° and -7°. The Janus has upper-surface airbrakes, and although uncommon the Janus C could also be fitted with a tail parachute. The Janus was superseded by the unflapped
Duo Discus which first flew in 1993; and the flapped
Arcus which first flew in 2009.
Production Schempp-Hirth Janus. 100 Januses were built by early 1980 plus three motorised Janus CMs. It is particularly suitable for instruction in cross-country flying in gliders with
wing flaps. ==Variants==