Horten Ho 33
Let us look at a post war development in Germany, before we return to my work in Argentina.
My brother Walter had remained in the old country, and sought to carry on with the Horten flying wing program. The opportunity came in 1951, when the building of sailplanes was again allowed. Walter choose the H III as the basis for his new airplane. He decided to make it a tandem two-place, with a 50 HP Zundapp engine mounted behind the rear seat.
Alfons Putzer, an old friend of ours, had the necessary skills and equipment, and built the Ho 33 within a years time. It flew as a pure sailplane in 1954. FVA in Aachen took over the machine the following year, and installed the engine. The certification process was slow and complicated, but it finally took off under its own power in March 1957.
Pitch oscillations were bothersome at first, and was corrected by relocating the c/g. The aircraft was flown for about three years before it was scrapped due to glue joint failures.
A second Ho 33 was finished in 1955, and flown successfully by several pilots, eventually accumulating over 40 hours of flying time. It behaved extremely well in the air, but was difficult to handle on the ground.
The commercial prospects for the aircraft were not good, as it was much too large and cumbersome for a two place ship. Plans to mass produce it were abandoned.
The Ho 33 V-2 now belongs to the Wasserkuppe Museum.
Specifications - Ho 33 V1
Usage | Motorglider |
Fuselage Construction | Wood |
Wing Construction | Wood |
Capacity | Two people |
Engine | Zundapp Z0-092 |
Power | 37 kW (50 HP) |
Span | 19.2 m |
Sweep Angle | 25 degrees |
Taper Ratio | 6.4 |
Wing Root Thickness | 20% chord |
Wing Root Depth | 3.2 m |
Rib Spacing | 0.25 m |
Wing Area | 35.6 m2 |
Aspect Ratio | 10.4 |
Pilot position | Seated |
Mid-section width | 2.4 m |
Cockpit width | 0.8 m |
Cockpit height (from seat) | 1.1 m |
Empty weight | 460 kg |
Ballast | water |
Additional payload | 226 kg |
Fuel | 14 kg |
Maximum weight | 700 kg |
Wing loading | 19.7 kg/m2 |
Power loading | 18.9 kg/kW |
Stall speed | 55 km/h |
Landing speed | 60 km/h |
Minimum Sink | 0.8 m/sec at 75 km/h and 18.3 kg/m2 loading |
Best Glide Ratio | 26:1 at 90 km/h and 18.2 kg/m2 loading |
Cruise Speed | ~175 km/h |
Maximum Speed (horizontal) | ~185 km/h |
Maximum Speed | ~240 km/h |
Schematic of the Ho 33 V-2
The Ho 33 V-1
The Ho 33 V-1
View from the hanger roof
The Ho 33 V-2