Glasflügel 604

The Glasflügel 604 was manufactured under severe time pressure in just four months for Walter Neubert to compete in the 1970 World Championships in Marfa.

The Glasflügel 604 has a three part wing with a 22 metre wingspan. The outer wings come from the Kestrel and are somewhat shortened. This results in a center piece of 7.5 m length, for which the original 17% thick profile was thickened to 20% for static reasons. To ensure strength, this middle section was quite heavy at 168 kg. The aircraft was supplied with a special trailer, which allowed the easy attachment of this middle piece by means of a crane swivel device. The set-up weight of the entire aircraft is 440 kg.

The fuselage and tailplane were also based on the Kestrel, but the dimensions had to be increased a bit. Thus, the fuselage is 0.88 m longer and also the mass balanced T-tail received increased area. These were only built between 1970 and 1973.

The prototype had the registration D-0604 and made its maiden flight on April 30, 1970. Dick Butler also became American Open Class Champion several times with his 604 (also the Protoype). Even at World Championships, the 604 was always at the forefront, and Walter Neubert held the world record for a long time over the 300 km triangle, which he flew at 153.43 km/h in Kenya in March 1972.  The prototype is a project in the USA today.

Dimensions
Wingspan                         22.00 m
Surface Area                    16.26 m²
Aspect Ratio                    29.8
Profile                               FX 67-K-170
Profile                               FX 67-K-150
Length                              7.56 m

Weight
Empty Weight                                  455 kg
Maximum Cockpit Weight             130 kg
Maximum Gross Weight                650 kg
Maximum Wing Loading               40.1 kg/m²

Speeds
Maximum Speed                              250 km/h
Stall Speed                                         66 km/h

Performance
Minimum sink at  75 km/h              0.53 m/s
Best Glide at 105 km/h                      49