There is nothing that would keep a Type 056 equipped with a hanger from launching and recovering an ASW helicopter safely and effectively. And if they equipped it with the proper equipment, it could do it in very healthy and strong sea states.I think that at a relatively low sea state and wind speed, compared with larger ships, a 056 will not be able to launch and recover a helicopter. That helicopter will be useless stored safely in a hangar.
They have a landing pad on the vessel already and we have seen Z-9s operating off of them. They are there for a reason and it is to be able to use the Type 056 as a temporary staging area for ASW helos that would then RTB after the mission.
With a hanger, they could stay on the ship, get refueled, be re-armed, and even have maintenance work done. That is not "useless", that would mean the helo is available there at sea with much more fuel for any mission they needed it for.
But, the PLAN figures, I am sure, that given the mission profile of the Type 056, it is just as well that the helo RTB for those things and that they keep the vessel at its current size and with its current capabilities. I understand that and have no problem with it. The vessel is a great design as is. This was all based on one simple comment of mine about something I thought they "might" have done to the Type 056..