The DG-300 has a flapless wing with triple taper based on the Hansjörg Streifeneder Falcon, and employs the HQ 21/II, a relatively thick profile (ca. 17.5%). This wing is 'blown' on the underside by 900 small holes to achieve a controlled transition from laminar to turbulent flow without additional drag. However, these holes are prone to clogging due to dirt, moisture and wing surface polishing, which makes them less effective over time. As with any racing glider, the thickness of the wing makes it relatively sensitive to performance degradation due to contamination by insect impacts or rain drops.
It is agile and a good climber, but slightly underperforms compared to its competitors in cruising flight, especially at higher speeds. The later DG-303 version with a new wing profile and winglets was developed that delivers higher performance at low to medium speeds plus increased aileron response. A fully aerobatic version (the Acro) was also sold, stressed for +7/-5g.
The DG-300 has typical DG features, which improve comfort and safety if at a performance cost. It has the large cockpit typical of DG giving excellent comfort, especially in high-altitude flight where the full-length canopy allows the feet to be warmed by sunlight. The view from the cockpit is superb, adding to the pleasure and safety of flight.
After the bankruptcy of Glaser-Dirks the newly founded DG Flugzeugbau GmbH took over the servicing of these gliders.
The operational limits were reduced in April 2007 after a defect was detected in the main spar which affects an unknown number of gliders. Consequently, the maximum speed and maximum manoeuvring speed was reduced to 135kts and 95kts respectively, maximum takeoff weight was restricted to 450kg, and aerobatic flight was prohibited - even for the Acro variants.[1] These restrictions are removed if both spars are inspected and it is confirmed that the defect is not present. However, if the defect is found, repair is impossible and the restrictions continue to apply.