Competition in the growing aircraft engine manufacturing segment is fierce. At stake is a market that is forecast to see 35,000 new planes produced over the next two decades

Of the 35,000 new planes to be built, 70% will be single-aisle aircraft. Airlines want these planes to be as fuel efficient as possible and the engine is the single most important part of that efficiency.

GE has early advantage with its LEAP technology                                                              
GE (NYSE:GE), through its partnership with Snecma, created an early lead in fuel efficient engines with its LEAP technology. LEAP engines are being used for Boeing's 737-MAX airplane. As of May, there had been over 2,000 orders for this plane.

Being being out in front in the narrow-body market may prove to be a huge advantage for GE. Of the 35,000 new planes to be built over the next 20 years 70% will be single-aisle planes. Being the exclusive manufacturer of the engines for the 737-MAX gives GE a sizable leg up in the battle for this market.

Competition for the Airbus 320neo                                                                                
Pratt & Whitney, a division of United Technologies (NYSE:UTX), is also competing in this game. The company produces an engine known as the geared turbofan, which has already proved popular with purchasers of the Airbus 320neo, capturing roughly half of the orders of this plane. Such popularity is proof that while GE has dominated in the short term, its long term role as dominant manufacturer might be under threat.

There remain roughly 1,800 A320neo orders outstanding for which an engine manufacturer has yet to be selected -- roughly $20 billion in orders. One big advantage Pratt & Whitney has over GE is that the first flights of the Airbus 320neo will take place later this year and will be using Pratt engines. Success with these first flights will go a long way toward making customers more comfortable with the Pratt engines.

Pratt & Whitney provided a little over 22% of United Technologies' net sales for the most recent quarter and roughly 18% of the companies' operating profit. The division is an important one and success with the A320neo will bring not only immediate results but also years of sales given that the customers sign a service and maintenance contract and are charged by hours flown.

Rolls-Royce ignores the narrow-body market                                                                    
(LSE:RR) has largely avoided the narrow-body market in favor of developing technologies for larger long-haul craft. It has had success in this area with the Boeing Dreamliner, and the Airbus' 380 Superjumbo and A350. 

The company's decision to ignore the narrow-body market has been a boon for GE and has provided Pratt & Whitney an opening to stage something of a comeback in the industry. 

As an example, consider the new venture by the Chinese airplane maker COMAC. This company is tasked with being China's first commercial aircraft manufacturer and threatening the Boeing and Airbus duopoly. Its C919 aircraft is a narrow-body craft whose engines will be GE's LEAP products. 

While delays have plagued the C919, many analysts predict that the plane, and company, will be a success. Not only is Rolls Royce not a player with COMAC, but unlike PRatt & Whitney, the company cannot even be a possible supplier for the company in the next decade. By ceding the narrow-body market to GE and Pratt & Whitney, Rolls Royce has assured itself on missing out on the market that is going to drive growth over the next two decades.

GE should maintain its leadership position in aircraft engine manufacturing over the next decade. Expect the company to widen its lead over Rolls Royce due to the latter ignoring the narrow-body market. If Pratt & Whitney can show success with the 320neo, then it likely will result in exceptionally strong growth in the next two decades.