Unlike the S10, the S6 has a non-retractable three-bladed propeller (that can feather, like other touring motor gliders), a wider fuselage design, and tricycle landing gear, available both with fixed and retractable configurations.

Its engine is a Bombardier-Rotax 914, the same engine used in the Stemme S10-VT.[2] The designers placed great importance on noise and vibration reduction.

The prototype S6 made its first flight on 29 November 2006 at Strausberg Airport, flown by Lothar Dalldorff.

It received EASA approval on 22 October 2008.

Data from Jane's All the World's Aircraft 2013-14.