|Competition class||15 metre|
|Cockpit width||0.62 m|
|Cockpit height||0.00 m|
|Wing area||9.88 m²|
|Wing profile||HQ 10-1642|
|Empty mass||ca. 235 kg|
|Water ballast||115 kg|
|Maximum mass||450 kg|
|Wing loading||ca. 32 - 45.55 kg/m²|
|Maximum speed||250 km/h|
|Rough air speed|
|Stall speed||60 km/h at 310 kg AUM|
|Minimum sink rate||ca. 0.57 m/s at 77 km/h|
|Glide ratio||ca. 42.7 at 96 km/h|
|Roll rate||ca. 3.5 s at 90 km/h |
-45º to +45º bank
The principal designer of the 304 was Martin Hansen, known for his role in the design of the Akaflieg Braunschweig SB-11. The glider continued the Glasflügel tradition of innovation: the parallelogram control stick, combined trailing edge flaps and airbrakes, automatic trimming, heel-operated brakes, automatic control connections, the extremely easy assembly of the wings and tailplane, the parallelogram forward opening canopy and lifting instrument panel are Glasflügel innovations largely copied by other manufacturers.
The prototype flew for the first time in May 1980 and entered production shortly after. Glasflügel was struggling by then, following the untimely death of Eugen Hänle, the founder of the company, in 1975. A partnership with Schempp-Hirth led to a surrender of technology. Lacking investment and an energetic leadership, the company folded in 1982.
The 304 was slightly less performing than the contemporaneous ASW 20 and did not succeed in top level competition. It enjoys however an excellent reputation for its flying qualities and craftsmanship.
The 304 was recently put back in production by the Czech company HPH Ltd, as the Glasflügel 304CZ. This new production run uses the original Glasflügel moulds and jigs that fortunately were not lost with the demise of the company. The 304CZ was updated with the addition of winglets and a few other changes, and has spawned several derivatives, namely a 17.43 m span variant, the Standard Class 304C Wasp and the recently completed 304S.
The 304 is sometimes referred to as the H-304, which is not correct, as the H applies only to the Glasflügel sailplanes designed principally by Wolfgang Hütter.