The E 78 Silene side-by-side two-seat sailplane was developed by CERVA (Consortium Europeen de Realisation et de Ventes d'Avions) and is the first French glassfibre two-seater. The company was owned by Siren SA and Wassmer-Aviation SA. The E 78 was designed by Siren and, following the closure of Wassmer, was transferred to Issoire in late 1977. The aim was to produce a sailplane suitable for all stages of glider training from ab initio to cross-country flights.

 

Construction was started in February 1973 and the prototype first flew at Argenton on 2 July 1974.

 

The wings are of glassfibre/plastic foam sandwich construction, incorporating two-section ailerons of similar material and Schempp-Hirth airbrakes operating both above and below each wing. Flaps are not fitted. The fuselage is a semi-monocoque glassfibre/plastic foam sandwich structure. The conventional tail unit incorporates a fixed incidence tailplane and trim tabs on each elevator.

 

The pilots sit in staggered position to keep the width of the fuselage to a minimum, the starboard seat being set slightly to the rear. The Silene is available with either retractable or fixed landing wheel with hydraulic brake and shock absorber.

 

E 78 Silene

Wing span: 18.0 m / 59 ft 0 3/4 in

Length: 7.95 m / 26 ft 1 in

Height: 1.5 m / 4 ft 11 in

Wing area: 18.0 sq.m / 193.8 sq ft

Wing section: Berlin E55 166

Aspect ratio: 18.0

Empty weight: 365 kg / 805 lb

Max weight: 565 kg / 1,246 lb

Water ballast: None

Max wing loading: 29 kg/sq.m / 5.94 lb/sq ft

Max speed: 119 kt / 220 km/h

Stalling speed: 34 kt / 63 km/h

Min sinking speed: 0.59 m/sec / 1.8 ft/sec at 39 kt / 73 km/h

Best glide ratio: 38 at 51 kt / 95 km/h