UFM Icarus II / Aeroplane

The Aeroplane is a single-seat single-engined biplane with two-axis control. Wings have swept back leading and trailing edges, and constant chord; no tail, elevator only. Pitch control by elevator at rear; yaw control by tip rudders; no separate roll control; control inputs through stick for pitch/yaw. Wings braced by struts and transverse X-cables; wing profile; double surface. Undercarriage has three wheels in tricycle formation; bungee suspension on all wheels. Nosewheel steering independent from yaw control. Brake on nosewheel. Aluminium-tube framework, without pod. Engine mounted between wings driving pusher propeller.
Designed by Larry Mauro, under the original title of Icarus II as a hang-glider, this famous biplane was one of the first hybrid control hang-gliders to be motorised (in 1975 by John Moody). It then pursued a remarkable career under the name of Easy Riser; by 1981 more than 900 were flying in the United States, built from plans supplied by Larry, or sold as kits by different firms such as UFM of Kentucky.
Since 1981, this company has offered it with an elevator added at the back of the inter-plane struts, in which form it carries the name Aeroplane. It is fitted with two-axis control and there is a fixed seat for the pilot, the hybrid control with the pilot moving in a swing seat having been abandoned. The rudders on the standard Aeroplane are hinged on the rear interplane struts at the wing tips. The engine is the Cuyuna 215R of 20hp, which as an option ($300) can be replaced by the 430R as on the Aeroplane XP, the three axis control version. The Aeroplane is sold either ready to fly for $5200 in 1983, or as a kit requiring 150h assembly for $3995. Options include floats for $900, transport covers for $250, skis, parachute and an instrument panel.
Whereas UFM of Kentucky has fitted the Easy Riser with a conventional tail giving rise to the Aeroplane (a 1983 model), Northstar had preferred a canard of variable incidence, thus acting as an elevator, for its Viking.
This rigid wing biplane has retrofit horizontal tail and strong spars. A joystick controls the elevator and drag tip rudders. Side mounted joy stick, rudder pedals, nose wheel steerable through rudder pedals. Single-cylinder Cuyuna 215R engine has reduction drive and is pusher mounted in the rear behind the pilot. It turns a 50-inch prop. Tricycle gear has 20-inch wheels which are shock-cord mounted and a 16-inch nosewheel with a wheel brake.
The Aeroplane XP is a single-seat single-engined biplane with conventional three-axis control. Wings have swept back leading and trailing edges, and constant chord; conventional tail. Pitch control by elevator on tall; yaw control by fin-mounted rudder; roll control by spoilerons on upper wing; control inputs through stick for pitch/roll and pedals for yaw. Wings braced by struts and transverse X-cables; wing profile; double-surface. Undercarriage has three wheels in tricycle formation; bungee suspension on all wheels. Push-right go-right nosewheel steering connected to yaw control. Brake on nosewheel. Aluminium-tube framework, with optional pod. Engine mounted between wings driving pusher propeller.
The Aeroplane XP is basically a three-axis version of the Aeroplane with a twin-cylinder engine. The design abandons the tip rudders of the Aeroplane in favour of a conventional tail, the stick and pedal arrangements being similarly conventional, with the stick mounted on the side of the framework.
One interesting point, however, is that both spoilers can be simultaneously deployed to act as air brakes; this is quite a common arrangement with pedal-actuated spoilers, but most unusual when the spoilers are actuated by the stick.
Options for the Aeroplane XP are as for the Aeroplane, except that UFM of Kentucky announced in March 1983 that a pod was available for the XP. Price is $4500 and the XP can be folded into a package measuring some 2 x 4 x 16 ft (0.6 x 1.2 x 4.9 m), allowing trailer or car-top transport. Rigging time is quoted as 50 min by one person.

Aeroplane
Engine: Cuyuna 215R, 20hp at 5500rpm
Propeller diameter and pitch 54 x 20 inch, 1.37 x 0.51 m
Reduction ratio 2.0/1
Power per unit area 0.12hp/sq.ft, 1.3hp/sq.m
Fuel capacity 5.0 US gal, 4.2 Imp gal, 18.9 litre
Length overall 11.0 ft, 3.35 m
Height overall 8.0ft, 2.44m
Wing span 30.0ft, 9.14m
Constant chord 3.4ft, 1.04m
Dihedral 15 deg
Sweepback 15 deg
Total wing area 170 sq.ft, 15.8 sq.m
Upper wing area 102.5 sq.ft, 9.52 sq.m
Lower wing area 67.5 sq.ft, 6.27 sq.m
Upper wing aspect ratio 8.8/1
Lower wing aspect ratio 5.8/1
Wheel track 4.5 ft, 1.37 m
Wheelbase 4.5 ft, 1.37 m
Nosewheel diameter overall 20 inch, 51 cm
Empty weight 180 lb, 82 kg
Max take-off weight 400 lb, 181 kg
Payload 220 lb, 100kg
Max wing loading 2.35 lb/sq.ft, 11.5kg/sq.m
Max power loading 20.0 lb/hp, 9.1kg/hp
Load factors +6.0, -4.0 design; +10.0, -5.0 ultimate
Never exceed speed 50 mph, 80 kph

Aeroplane XP
Engine: Cuyuna 430R, 34hp at 6000rpm
Propeller diameter and pitch 54 x 30 inch, 1.37 x 0.76 m
V-belt reduction, ratio 2.0/1
Max static thrust 250 lb, 113 kg
Power per unit area 0.20 hp/sq.ft, 2.2 hp/sq.m
Fuel capacity 5.0 US gal, 4.2 Imp gal, 18.9 litre
Length overall 11.0 ft, 3.35 m
Height overall 8.0ft, 2.44m
Wing span 30.0ft, 9.14m
Constant chord 3.4ft, 1.04m
Dihedral 15 deg
Sweepback 15 deg
Total wing area 170 sq.ft, 15.8 sq.m
Upper wing area 102.5 sq.ft, 9.52 sq.m
Lower wing area 67.5 sq.ft, 6.27 sq.m
Upper wing aspect ratio 8.8/1
Lower wing aspect ratio 5.8/1
Wheel track 4.5 ft, 1.37 m
Wheelbase 4.5 ft, 1.37 m
Nosewheel diameter overall 20 inch, 51 cm
Tailplane span 8.5ft, 2.59m
Fin height 3.5ft, 1.07m
Empty weight 225 lb, 102 kg
Max take-off weight 475 lb, 215 kg
Payload 250 lb, 113kg
Max wing loading 2.79 lb/sq.ft, 13.6kg/sq.m
Max power loading 14.0 lb/hp, 6.3kg/hp
Load factors +6.0, -4.0 design; +10.0, -5.0 ultimate
Max level speed 55 mph, 88 kph
Never exceed speed 55 mph, 88 kph
Max cruising speed 50 mph, 80 kph
Economic cruising speed 40 mph, 64 kph
Stalling speed 22 mph, 35 kph
Max climb rate at sea level 1200 ft/min, 6.1 m/s
Min sink rate 290 ft/min at 30 mph, 1.5 m/s at 48 kph
Best glide ratio with power off 8/1 at 28 mph, 45 kph
Take-off distance 75 ft, 23 m
Landing distance 100 ft, 30 m
Service ceiling 18,000 ft, 5490 m
Range at average cruising speed 125 mile, 201 km

Aeroplane XP-2
Engine: Cuyuna, 43 hp or Rotax 47 hp
Wingspan: 32 ft
Wing area: 196.5 sq.ft
Empty wt: 250 lbs
Max wt: 700 lbs
Cruise: 55 mph
Stall: 26 mph
Vmax: 63 mph
ROC: 600 fpm
TO run: 100 ft
Ldg roll: 100 ft