When you put a sharp pencil to the concept, diesel engines should be a slam dunk against gasoline engines. Their fuel specifics are terrific, they have lots of torque and, potentially, they have long overhaul cycles. Modern ECU-based diesels have headroom on both performance and economy, so it’s realistic to expect improvements in both.
Yet, the market sort of stumbles along, even with avgas at $6-plus and looking increasingly threatened with extinction in Europe, if not in the U.S. If you add up recent production figures, gasoline aircraft engines continue to outsell diesel options by a wide margin. While it’s true that the diesels from Diamond are making inroads, it’s also true that Diamond is the only major OEM with a serious diesel program.