Designer Kevin McGrath wanted to produce an aircraft which could be flown regularly even in British weather conditions, so he deliberately made the wing loading as high as possible within the British microlight definition and gave the aircraft a snug cockpit. The transparent canopy at the front hinges at the top to allow entry and exit and can be removed completely for summer days. Another novel feature is that behind the pilot is a compartment suitable for 13 lb (6 kg) of baggage.
Introduced in prototype form at the beginning of 1983, the Aeolus is most notable for its fully enclosed glass fibre fuselage; this is a structural part of the aircraft rather than just a pod, and supports the engine at the rear.
A single seat, single engined high wing mono¬plane with conventional three axis control. The wing has unswept leading and trailing edges, and constant chord, with a conventional tail. Pitch control is by elevator on the tail; and yaw control by fin mounted rudder; roll control is by full span ailerons; with control inputs through stick for pitch/roll and pedals for yaw. The NACA 63412 profile; 100% double surface wing is braced from above by struts and cables, from below by struts. The undercarriage has three wheels in tail dragger formation; steel spring suspension on the tailwheel and aluminium spring suspension on the main wheels. No ground steering (tailwheel castors) or brakes are fitted. The glassfibre fuselage is totally enclosed, and the engine is mounted below the wing, driving a pusher propeller.
The prototype machine was to be modified for production, using V belts instead of a toothed belt reduction drive. Other changes for production included a 25% increase in tailplane and elevator areas, a reduction in aspect ratio from 7.3 to 5.6/1, a more rigid wing of composite construction with heat shrunk fabric skin and strut bracing, plus replacement of the coil spring suspension on the main wheels by a wire-braced aluminium cantilever arrangement.
Prototype
Engine: Robin EC34PM, 30 hp at 7500 rpm.
Max static thrust: 160 lb, 73 kg.
Propeller: 53 x 36 inch, 1.34 x 0.91 m.
Reduction: Toothed belt ratio.
Length overall: 17.0ft, 5.18 m.
Height overall: 5.5ft, 1.68m.
Power/unit area: 0.21 hp/sq.ft, 2.3 hp/sq.m.
Fuel capacity: 6.0 USG, 5.0 Imp gal, 22.7 lt.
Wing span: 32.0ft, 9.76m.
Constant chord: 4.4ft, 1.34m.
Dihedral: 2 degs
Sweepback: 0 degs
Tailplane span: 7.5ft, 2.29m.
Fin height: 4.0ft, 1.22m.
Total wing area: 140 sq.ft, 13.0 sq.m.
Aileron area: 9.0sq.ft 0.84 sq.m.
Fin area: 3.0 sq.ft, 0.28 sq.m.
Rudder area: 5.0 sq.ft, 0.46 sq.m.
Tailplane area: 15.0sq.ft, 1.39 sq.m.
Elevator area: 10.0 sq.ft, 0.93 sq.m.
Wing aspect ratio: 5.6/1.
Wheel track: 4.0ft, 1.22m.
Wheelbase: 11.0ft, 3.35m.
Tailwheel dia: 4 inch, 102 mm.
Main wheels dia: 12 inch, 305 mm.
Empty weight: 280 lb, 127kg.
MTOW: 550 lb, 249kg.
Payload: 220 lb, 100 kg.
Max wing load: 3.92 lb/sq.ft, 19.1 kg/sq.m.
Max pwr loading: 18.3 lb/hp, 8.2kg/hp.
Load factors: +4.0, 2.0 design; +6.0, 4.0 ultimate.
Max level speed: 65 mph, 105 kph.
Vne: 80 mph, 129 kph.
Max cruise: 58 mph, 93 kph.
Economic cruise: 58 mph, 93 kph.
Stalling speed: 28 mph, 45 kph.
Max climb SL: 550 ft/min, 2.8 m/s.
Best glide ratio: 11/1 at 45mph, 72kph.
Take off dist: 200ft, 60m.
Landing dist: 200ft, 60m.
Service ceiling: 10,000ft, 3050m.
Range ave cruise: 120 mile, 193km.
