There is not a lot of details on the BAHR flying wing. The small article in the periodical says what follows :  "This summer (in 1957) there was a glider contest, the Gunther cup, organized for the purpose of demonstrating that the RHÖN, despite its area border proximity, was still interesting for soaring.  Among the 12 gliders presented by Germany, there was the one presented.  This tailless aircraft was built in 3 years by Mr. Johannes Bahr.  Mr. Bahr is not the pilot but he was wishing to present his aircraft to the other pilots before the certification.  It is piloted in prone position."