Paulet would go on to visit the German rocket association Verein fr Raumschiffahrt (VfR) and on March 15, 1928, Valier applauded Paulet's liquid-propelled rocket design in the VfR publication Die Rakete, saying the engine had "amazing power".[3] In May 1928, Paulet was present to observe the demonstration of a rocket car of the Opel RAK program of Fritz von Opel and Max Valier, and after meeting with the German rocket enthusiasts.[3] VfR members began to view black powder as a hindrance for rocket propulsion, with Valier himself believing that Paulet's engine was necessary for future rocket development.[3] Paulet would soon be approached by Nazi Germany to help develop rocket technology, though he refused to assist and never shared the formula for his propellant.[1] The Nazi government would then appropriate Paulet's work while a Soviet spy in the VfR, Alexander Boris Scherchevsky, possibly shared plans with the Soviet Union.[4]