1923: Edgar Buckingham at the United States National Bureau of Standards publishes a report on jets, coming to the same conclusion as W.J. Stern, that the turbine engine is not efficient enough. In particular he notes that a jet would use five times as much fuel as a piston engine.[22] 1925: The Hesselman engine is introduced by Swedish engineer Jonas Hesselman represented the first use of direct gasoline injection on a spark-ignition engine.[23][24] 1925: Wilhelm Pape patents a constant-volume engine design.