Flying without shame Air-traffic is rightly considered one of the big climate killers. Enormous efforts and capital are being spent to make flying environmentally friendly. In development are electrically powered aeroplanes, hydrogen-powered aeroplanes or aeroplanes powered by e-fuels, etc. All the technologies described here are either technically unrealistic and extremely costly, or both. None of these concepts is viable and at best serves as a fig leaf! The feasible alternative We show you on the video how well conventional jet-engines can be powered by vegetable oil. With a little modification of the PRE-FUEL fuel, all aircraft powered by jet-engines could be operated with PRE-FUEL in the near future. This means - flying without shame - because here, too, every kilometre flown would relieve the environment through the PRE-FUEL PARADOX.