To increase its coastal research capabilities and sea-going range, the 23m long and 6.35m wide vessel was cut and a new midship section inserted. That increased length by 8m to 31m, although original plans showed planned lengthening to 32.5m. It was not immediately clear why GKSS had changed its mind.

The conversion increased weight from 130-250 tons, draught from one to 1.5m and side height from 2-3m and so increased ship stability considerably. Two new 375kW diesels replaced an old 2x185kW drive configuration while propulsion was provided by two SRP 200 rudder propellers. An SPJ 57 RD Pump Jet of 100kW capacity, driven by an electric motor, was also installed as was a new Palfinger crane. The changes meant that crew members can now easily swap mobile laboratory containers.

SET noted all that remained of the old ship after the conversion was some nautical equipment, parts of the stern, a bow section, the wheelhouse and the mast. "Ludwig Prandtl after conversion and in her 'new outfit' was pretty much a new ship", the German yard said.