When people talk about PLAN in the West, the modernization and the naval shipbuilding program are often the focus. There is no question that the current shipbuilding program for both PLAN and the Coastal Guard agencies are impressive. However, China began this streak from a very low starting point. What people often miss is how PLAN keep really old and ineffective ships in service to save cost.
Among the frigates that are still in service, no where is more evident than the 4 Jianghu-I ships that are still in service with East Sea Fleet. The 513 and 514 ship shown below first joined PLAN in the 70s and really have no use other than training and patrols. In fact, 2 Jianghu-I ships have already been converted for the Maritime Police agencies (much to their chagrin I must add).
Another big example of extremely old PLAN ships are the Luda destroyers in service with North Sea Fleet as covered by China-defense blog. The sailors on this 40 years old ship is their newly issued cold weather gears. Some of them are still using silkworm anti-ship missiles, manually controlled AAA guns for air defense and antisubmarine rocket launchers for ASW.
At the same time, the current upgrade program gives us an insight on the extension of the relative old ships still in service with PLAN.
The 052 Luhu class ships (112 & 113) joined PLAN after a full production run of the 3600-ton Luda class. These 4200-ton class ships were the first PLAN surface combatants to use gas turbines. 112, the lead ship of the class, uses LM-2500 (imported before the embargo) and joined service in 1994. 113, the other ship of this class, had to use GT-25000 and joined service in 1996. These two ships were upgraded once in 2003/2004 to use YJ-83 anti-ship missiles and upgraded main guns. However, their current weapon systems are vastly outdated when compared against the similar sized 054A class. They are still using HQ-7 and outdated Type 76A guns for air defense. 112 uses a bunch of imported (and now outdated) sensors and combat system. Due to the arms embargo, 113 was forced to use the downgraded domestic copy of those sensors and combat system. Either way, support for these sensors are unlikely to be too great going forward. At the same time, it's usage of Z-9C helicopters, DUBV-43 VDS and DUBV-23 hull mounted sonar are unlikely to allow it to fully perform its original designed role of ASW destroyer.
As such, it appears that 112 is undergoing a hull scale of changes for the past year at the HuDong shipyard. It is likely that LM-2500 will be replaced by QC-280 after 20 years of service. At the same time, the rest of the ships have been ripped apart. I have not seen this kind of upgrade with any other PLAN ships. When looking at the amount of work they are performing on this ship, it makes me wonder why they do not just use that money to build more 054As. Either way, it looks like 112 will remain in service for another 20 years after this kind of mid-life rebuild.
Also as stated in a recent China-defense blog entry (originally from fyjs forum), the Jianghu-V ships are getting an extensive refitting. These 6 ships were built for the South Sea Fleet from 1992 to 1995. They were the result of an emergency program at that time due to the worsening situation in South China Sea. Today, it is hard to see PLAN needing such a program these days to protect its waters, but China did have tough time against the Vietnamese there in 1988. Compared to other Jianghu ships, these ships had more modern and reliably sensors/weapons and much better living quarters. It's certainly not easy for sailors to stay out for long patrols in South China Sea without air conditioning. Even so, these ships are really archaic in terms of hull design, sensors and weapon systems. From the photos below, we can see that they have installed two quadruple YJ-83 launchers, PJ-33A dual-100mm guns, new air search radar and decoy launchers.
From these recent photos of the inside of the ship, it looks like they have also installed new control terminals and combat systems.
The last two photos were taken from 562 conducting New Year's patrols. It is clear that these ships still play a very important part in patrolling the coastal waters. With the extensive refitting we are seeing, they are likely to be in service for quite sometime. So even with the induction of many 054As, PLAN still consist of a large number of old ships.