Editing DFS 346 (section)

===First accidents===
[[File:346 ES.svg|thumb|150px|Pilot escape sequence]]
Newly built '''346-1''' incorporated minor aerodynamic refinements over the 346-P, and was first flown by Ziese on September 30, 1948, with dummy engines installed. The glider was released at an altitude of 9700 m, and the pilot realised that he hardly could maintain control of the aircraft. Consequently, while attempting to land, he [[Descent (aircraft)|descended]] too fast (his speed was later estimated at 310&nbsp;km/h). After first touching the ground he bounced up to a height of 3–4&nbsp;m and flew 700–800&nbsp;m. At the second descent, the landing ski collapsed and the fuselage hit the ground hard.<ref name="dfs">Deutsche Flugzeuge in russischen und sowjetischen Diensten</ref>

The pilot seat structure and [[seatbelt|safety-belt]] proved to be very unreliable, because at the end of a rough braking course Ziese was thrown forward and struck the canopy with his head, losing [[consciousness]]. Luckily, he wasn't seriously injured, and after treatment in hospital he was able to return to flying. Accident investigation research team came to the conclusion that the crash was a result of pilot error, who failed to fully release the landing skid. This accident showed that the aircraft handling was still very unpredictable, as a result, all rocket-powered flights were postponed until pilots were able to effectively control the aircraft in unpowered descent, requiring further [[gliding|glide]] flights.<ref name="dfs"/>

The damaged 346-1 was later repaired and modified to '''346-2''' version. It was successfully flown by test pilot P.&nbsp;Kazmin in [[1950 in aviation|1950]]-[[1951 in aviation|1951]] winter, but nonetheless these flights also ended "on fuselage". Furthermore, after the last flight of these series, the [[airframe]] again required major repairs. On 10 May 1951, Ziese returned to the program, flying final unpowered test flights with the 346-2, and from 6 June, unpowered tests of the 346-3 without accidents.<ref name="dfs"/>