The Blume Bl.500, Bl.502, and Bl.503 were a family of four-seat light aircraft designed in West Germany by Dr Walter Blume in the late 1950s.

Derived from his Arado Ar 79, the basic design shared by all models was that of a conventional low-wing cantilever monoplane with retractable tricycle undercarriage and all-metal construction. The Bl.500 prototype was built for Blume at the Focke-Wulf plant and was powered by a Lycoming O-320 engine of 112 kW (150 hp). This led to a modified version, the Bl.502 that achieved German type certification and was offered for sale alongside the generally similar Bl.503 with a more powerful engine. However, no orders were forthcoming and Blume abandoned the project.

The final example of the design, the Blume Bl.503 was still active in 1965.

Bl.500

prototype

Bl.502

intended production version with Lycoming O-320

Bl.503

proposed production version with Lycoming O-360. A single example was completed.

Data from Jane's All The World's Aircraft 1961–62^[1]

General characteristics

• Crew: 1
• Capacity: 3 passengers
• Length: 8.15 m (26 ft 9 in)
• Wingspan: 10.50 m (34 ft 5 in)
• Height: 2.40 m (7 ft 10 in)
• Wing area: 15.0 m² (161 sq ft)
• Aspect ratio: 7.35:1
• Empty weight: 670 kg (1,477 lb)
• Gross weight: 1,120 kg (2,469 lb)
• Powerplant: 1 × Lycoming O-320 air-cooled flat-four engine, 110 kW (150 hp)

Performance

• Maximum speed: 250 km/h (160 mph, 130 kn)
• Cruise speed: 220 km/h (140 mph, 120 kn) (70% power)
• Range: 900 km (560 mi, 490 nmi)
• Endurance: 4.1 hr
• Service ceiling: 4,800 m (15,700 ft)
• Rate of climb: 5.11 m/s (1,005 ft/min)
• Takeoff distance to 15 m (50 ft): 375 m (1,230 ft)

Related development

• Arado Ar 79