Why Some Aircraft Come With Different Engine Options


Today we thought we would take a look at why some aircraft manufacturers offer their planes with different engine options and the reasons behind why they do this. Looking at the overall picture, you would assume that Airbus and Boeing would figure out the best engine option for the plane they were building and go with one engine design. The truth, however, is not as black and white as you would initially think.

United 787-10
The GEnx-1B engine is the best-selling engine on the Boeing 787 Dreamliner. Photo: Getty Images

When purchasing aircraft for their fleets, different airlines have certain criteria they are looking to meet when selecting what engine option is more suitable for how they plan on operating the plane. For example, some will be looking for an engine that is more suitable for flying short-haul routes, while others will be looking for something designed for long-haul operations.

Some engines cost more than others

Cost and politics may also play a part in what engine option an airline will choose with certain airlines, like British Airways preferring to buy a British built engine like Rolls-Royce made by British workers over an engine manufactured in the United States. Different countries also have tariffs that can increase an engine’s cost depending on where it was manufactured.

COMAC has six C919 test aircraft flying, all fitted with the Leap-1C. Photo: Getty Images

While British Airways may select a British-built engine to look good in the British public’s eyes, some countries have sanctions placed on them. These sanctions may limit who airlines operating in certain countries can buy aircraft and engines from. China and its COMAC C919 narrow-body jet being built to compete with the 737 and A320 family of planes is an example of where politics plays a part in which engine options are available. Last year, the Trump administration was weighing whether to ban the General Electric/Safran-built engines’ sale to China. Some officials were worried that the Chinese would copy the engine and produce their own variant cheaper than the American/French-built engine.

Offering different engine options adds to sales

The reason Lockhead no longer builds commercial aircraft for airlines can be put down to the L-1011 TriStar and the fact that the plane only came with one engine option, the Rolls-Royce RB-211. Rolls-Royce was having difficulty delivering the engine to Lockheed and even went into receivership before being rescued by the British government.

The Lockheed L-1011 only came with one engine option. Photo: Aero Icarus via Wikipedia

The delays in getting the engine to Lockheed allowed competitor McDonnell Douglas to get its DC-10 to the marketplace a year before Lockheeds TriStar. If Lockheed had different engine options available, the L-1011 might have proved to be much more successful than it was.


Airlines select engine options for different reasons.

As we already mentioned, politics and public opinion may drive what engine option an airline will select depending on what country it is affiliated with. Some airlines may opt for the cheapest option available, while others could go with a certain variant due to maintenance. If you have a fleet of planes like the Airbus A320 powered by the CFM56-5B, why would you suddenly want to order new planes with a different engine? Your mechanics are used to working with one engine. Having spare parts available for that specific engine type is easier to manage than it would be if you were working with multiple engines made by different manufacturers.

GE 777X engine
The GE9X is the world’s largest and most powerful commercial aircraft engine and will power the Boeing 777X. Photo: GE

Truth be told, airlines are only thinking about price and operating costs, which means if one engine’s option price and its reliability and length of life are better than another, that is the engine they will select.


If you can think of other reasons why planes come with different engine options, please let us know in the comments.