These two companies offer diesel aircraft engines, here’s why – Jalopnik

Despite the original diesel fisco in the 2010s – and the five carmakers undergoing their own Dieselgate trial in Britain this year – diesel engines have clear advantages over their petrol counterparts. As a result, applications such as long-distance freight, cruise ships, trains and heavy equipment are still in high demand. And while it may surprise some people here in the United States, the efficiency and low cost of ownership that come with diesel engines can make them an excellent choice in the air, too.

This is especially true in many parts of the world where the supply of aviation-grade gasoline is limited or non-existent. The situation is driving up the cost of avgas, making gas-powered piston-engine aircraft difficult to sell. To be clear, diesel aircraft do not solve the problem by using diesel fuel. They run on the much more commonly used Jet A fuel, or a variant thereof.

Remember, diesel engines are named after their inventor, Rudolf Diesel, and not their fuel. The defining characteristic of its engines is that they rely on compression, not spark plugs, for ignition. The chemical composition of Jet A, based on kerosene, is compatible with that process. Today, at least one company – Piper Aircraft – is trying to expand its reach in the US. Meanwhile, Diamond Aircraft has been doing the same in Europe since 2002. The diesel revolution has also been a long time coming, since the first airplane with a diesel engine took off in 1928.

After 1928 there had of course been some diesel aircraft. For example, diesel engines were used in some Nazi fighter planes, leading to one of the strangest engines ever built. But overall, they lost out to the improved performance of gas and jet engines in the years that followed – when avgas seemed plentiful enough and people weren’t so concerned about its lead content. But as time went on and demand for avgas continued to exceed supply in Europe, companies began to reconsider diesel aviation technology. This also included the German Thielert Engines, which developed one of the first diesel engines certified for European aviation applications.

Thielert’s Centurion 1.7, which can run on diesel or unleaded Jet A, was chosen by Diamond Aircraft for its innovative DA40 TDI Diamond Star, the first mass-produced General Aviation aircraft to be certified in Europe. The turbodiesel showed better fuel economy while running on cheaper, more readily available jet fuel

Another major innovation for Diamond was the development of its own diesel engines to replace the Thielert plants that had proven problematic in the real world, leading to the company’s bankruptcy and eventual ownership by China’s AVIC International. Founded in 2007, Diamond’s Austro Engines now powers Diamond Aircraft such as the DA50 RG, which achieved a major milestone by achieving Transport Canada certification this year.

Founded in 1937, Piper Aircraft rose to prominence during World War II when the single-engine propeller plane – the Piper Cub – became popular with the armed forces as everything from a supply plane to an air ambulance to a trainer for new pilots. And that’s despite the fact that at least one Porsche 911 can ride higher than the Piper Cub can fly.

Flash forward to 2014 and we see Piper introduce the Archer DX, the first aircraft with a diesel engine. The Archer DX was developed specifically to address the avgas situation outside the United States, but its success led to Piper’s current US-focused efforts: the Piper Seminole DX was announced this summer and featured a pair of liquid-cooled four-cylinder turbodiesel engines manufactured by DeltaHawk, with Piper landing its first US order just a few months later.

Those first were at the Skyborne Airline Academy, which will use the planes as trainers to take advantage of their diesel-derived benefits. Per Piperthe DeltaHawk engines deliver a 35% improvement in fuel efficiency over the previous gas Seminole, while also enabling a 32% faster climb rate for single-engine and a 70% higher ceiling for single-engine. In addition, because diesel engines do not require components such as spark plugs or magnets to initiate combustion, they have fewer moving parts, which reduces maintenance and repair costs, and their liquid cooling further reduces the risk of overheating.