Can anyone explain me why PLAN has one helo per ship? Does it have anything to do with relatively low ratio of helicopters to ships? Helos are notorious for low availability and facilities for a second helo doesn't double aviation facilities.
Also to do with fleet composition.
USN Burkes need dual hangers because they are expected to operate independently, while PLAN major surface combatants rarely operation solo outside of peacetime routine patrol duties close to home waters. There is less need for a second helo on your DDGs when you can sent a FFG as a buddy when needed.
One of the main reasons for the 054B is to be able to better keep up with DDGs and carriers for long range missions/patrols.
The 054As will remain closer to home waters as a second line patrol and defence asset used largely for convoy close protection and low threat environment patrols while the 054Bs, DDGs and carries form the long range expeditionary fleet elements.
While having dual hangers is indeed better than single helo hangers, it’s largely a good-to-have feature for PLAN ships rather than must-have as is the case for most other navies.