China’s long-serving aircraft carrier, the Liaoning, boasts a small fleet of troubled J-15s and, as of 2016, only 25 qualified pilots. Now, as the Chinese test and expedite production of two new domestically developed aircraft carriers, they face a number of significant challenges. Their goal is to become a true “blue water” Navy. But they still have much ground to cover—no matter how many carriers they can field.

On Sunday, the People’s Liberation Army-Navy (PLA-N ) launched a new recruitment effort. Its aim is to end the carrier-based pilot shortage, as the nation prepares to triple its carrier presence and accompanying squadrons.

“The highlight of this year’s recruitment is the selection of future carrier-borne aircraft pilot cadets. Through shifting from ‘shore-based’ to ‘carrier-based’ standards, the PLA Navy aims to build a pilot recruitment system with Chinese naval characteristics that can adapt to carrier-borne requirements,” the official statement from the Chinese military reads.

However, even if this new recruitment push for capable pilots is successful, it might not be enough to make China’s carriers a formidable presence even in their own regional waters. To begin with, China’s new home-built carriers still rely on diesel-electric propulsion systems. Consequently, their operational area is restricted by the need for constant refuelling.  A Navy that is beholden to fuel limitations and is therefore forced to remain close to friendly shores is often referred to as a “green water” force (Navies that don’t face such restrictions are called “blue water”).