Diesel Aviation

A giant new development is being made in the aircraft manufacturing industry as traditional Avgas engines are being replaced by engines powered by diesel fuel. There are many different concerns and criticism about whether these new engines will be proficient enough to power piston driven airplanes. Replacing avgas with diesel is a very heated topic within general aviation because it could change the way pilots fly in the future. However, there are also many benefits to having diesel engines that has many experts wondering why companies haven’t completely switched over to the fuel already.

In the early years of aviation before the jet age, planes were powered by a high octane leaded fuel, similar to when cars used gas that had lead in it. Over the years it was discovered that lead was extremely detrimental to the environment and cars completely switched over to unleaded gas. However, aviation fuel converted to 100LL, which still has a small percentage of lead in its composite. Now, the Environmental Protection Agency is alleging that airplanes flying in high elevations are pumping lead into the atmosphere. This concern sparked the debate that a new fuel source should be used to power these airplanes. The decreasing reserves of Avgas is one of the greatest reasons that a demand for change has occurred and eventually prices will be so high that flight training will become a more difficult financial challenge

Diesel fuel was considered to be the best method used in converting from 100LL because it is less expensive and has a slightly better fuel economy than Jet A. However there are some negative aspects of diesel that would deter many pilots from switching over to the new source of power. The first problem is one that is occurring today but could worsen once diesel becomes popular in airplanes. There have been numerous accidents in general aviation when pump attendants fuel airplanes with Jet A instead of 100LL. When this happens the engine can run from taxi to takeoff and will cut out when the airplane is about 100 feet in the air. Pilots prevent this from occurring by checking the fuel during preflight to insure that it has a blue color and doesn’t smell like kerosene. When diesel is introduced into the market it is very hard to determine what fuel it is because it has the same color and smell as Jet A. Studies have also shown that diesel causes filter plugging and possible fuel starvation under high-altitude, low-temperature operation.

One of the latest aircraft models that changed to using a diesel engine is a Cessna Model 182.
SMA, a company in France, began developing the diesel aircraft engine back in 1998 and just released the engine that Cessna has installed in the 182. SMA has also produced diesel engines for the Piper Dakota and Seneca, Socata Trinidad and Cessna Skyhawk. The company is also developing six-cylinder, 300 to 350 hp models for possible use on large singles and medium twins. As other companies such as Lycoming and Continental begin to compete for top spot in the market for this new phenomenon, many are anticipating the best for diesel aviation.