Boeing has selected a 68-inch fan diameter for its new 737 MAX family, which will be powered by CFM International LEAP-1B engines.

The company said a 68-inch fan diameter fan will offer the Max family of aircraft optimsed engine design and provide the lowest fuel burn and operating costs in the single-aisle aircraft market.

The company had previously said the 737 MAX would have a CFM International LEAP engine with a 66-inch or 68-inch fan, depending on a final decision on the weight and efficiency.

Boeing said the 68-inch fan will offer savings in fuel burn, drag on the airplane and also additional weight on the airplane.

The 737 MAX family aircraft will use less fuel than the A320neo, despite the smaller fan as it is lighter, as the current 737-900ER weighs 50 pounds less per seat as compared to the A321.

Boeing is planning to take the first flight of the 737 MAX by 2016 and deliveries to customers are expected to start in 2017.