The bigger issue was a configuration issue with the plane, itself. That Rhutan design has a pretty spindly nosewheel and you can start the engine with the nose resting on the ground and then lift the nose and extend the wheel. For that purpose the aircraft has a little primer tank. The intended purpose is to get the engine started then switch to the main tank for all taxiing and flying. In practice, I understand from a friend who accidentally tried it, that the primer tank will get you 10-12 minutes of flying. Then things get a little quiet. A quick hand can switch the tanks before completely losing the engine.
In what might be called a Stupid Previous Owner Trick, the valve to switch tanks was moved from a location you could get to while seated in the cockpit to one you couldn’t reach. He took off, exhausted the primer tank and couldn’t switch to the main.