I would identify what the major problems are and go from there?
Specifically, what is wrong with the design? (Facts, not emotions please)
On a more constructive note...If I were to redesign it I would build two of the 2D frames in a V shape, widest at the firewall and coming together at the tail.
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I agree with Aerowerk. The Base Design has to first catch the Builders Eye, then his Budget, and then his Expertise to Build it. Anything can be Improved upon. Many of these Old Airplanes weren't Designed by Engineers, and most were never Patented!
It's 3D Modeled on some different websites, here is the Airframe.
https://grabcad.com/library/afford-a-plane-model
How much easier could it be than Gussets & Rivets, and Nuts & Bolts.
First, you have to decide what you want a Legal part 103 Ultralight or a Light Sport Aircraft?
What kind of Materials do you want to use 6061, Carbon Fiber, etc?
What Engine do you want to use?
The Plans are Free/Cheap on the Internet/eBay!
Visit the different Affordaplane Groups and make up a list of all the Pros/Cons of the Plane and what you think needs changed. You could swap out the Square Tube to Round Tube and maybe Save some Weight. The Landing Gear looks like one of the main weak points.
AIR BIKE and a AFFORDAPLANE with a better Landing Gear.
Affordaplane Spec's:
Crew: one
Capacity: one (ultralight configuration)
Length: 17 ft 3 in (5.26 m)
Wingspan: 27 ft 5 in (8.36 m)
Height: 5 ft 0 in (1.52 m) varies by main landing gear wheel diameter
Wing area: 123 sq ft (11.4 m2)
Empty weight:
254lb (115kg)
Gross weight: 540lb (245kg)
Useful Load:
286lbs -30lbs(Gas) = 256lbs for Pilot & Bags.
Fuel capacity: 5 US gallons (19 litres)
Powerplant: 1 × Rotax 277 2-stroke gasoline,
26 hp (19 kW)
Propellers: 2, 3, or 4-bladed composite (preferred) or wood
Performance:
Maximum speed: 63 mph (101 km/h; 55 kn)
Cruise speed: 55 mph (89 km/h; 48 kn)
Stall speed: 26 mph (42 km/h; 23 kn)
Never exceed speed: 75 mph (121 km/h; 65 kn)
Range: 150 mi (130 nmi; 241 km) estimated
Service ceiling: 10,000 ft (3,000 m) estimated
Rate of climb: 1,000 ft/min (5.1 m/s) estimated
Wing loading: 4.39 lb/sq ft (21.4 kg/m2) Part 103 compliant at MTOW
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Specifications (
Airbike with Rotax 447)
General characteristics:
Crew: one
Capacity: no passengers
Length: 16 ft 0 in (4.88 m)
Wingspan: 26 ft 0 in (7.93 m)
Height: 5 ft 6 in (1.68 m)
Wing area: 118 sq ft (10.98 sq m)
Empty weight:
257lb (116 kg) <-- Could make it with a 377, or use a Belt Drive.
Useful load:
303lb (137 kg)
Max. takeoff weight:
560lb (254 kg)
Powerplant: 1 × Rotax 447 fixed pitch,
40hp (30 kW)
Propellers: 1 propeller, 1 per engine
Performance
Maximum speed:
80 mph (130 km/h) <--- Full Power Speed with 40hp to High for Part 103.
Cruise speed:
63 mph (102 km/h)
Stall speed:
30 mph (49 km/h) <---Doesn't make 24kt Stall Speed.
Range: 150 nautical miles (279 km)
Rate of climb: 1000 ft/min (5.1 m/s)
Wing loading: 4.75 lb/sq ft (23.1 kg/sq m)
Power/mass: 14 lb/hp (0.12 kW/kg)
With a Rotax 277(26hp) 268.8cc, or a Hirth F-33(28hp) 313cc it would make Part 103 Weight and either one with a Good Tuned pipe could make around 32-35hp.
