Timelines,
In 2009, the Hong Ha shipyard started to build the first TT-400TP, a 400 tonnage gunboat by modular method, and completed after over 2 years in 2011. The director said that they sent engineers oversea to study on this method maybe since 2004.
In 1999, Vietnam bought 2x of Molniya built entirely in Russia. 2007 received.
In 2011 they started to build Molniya domestically in BaSon shipyard, and integrated weapons on it.
In 2006 contracted for 2 first Gepards, received 2010
2016 next 2 Gepard on going build, no domestic plan.
2009-2010 rumor about Sigma-class started
2011 first DN-2000 start, 2016 8x DN completed, no Sigma-class updated.
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I found a link between these.
Engines are not problem to Vietnam, no matter they're Ukraine or German.
It could be translated as:
Vietnam bought 2x first Molniya boats for training and performance test, while keep negotiating on KH-35 production line.
They ever think about buying or build Molniya based on detailed design at high price or just buy the basic design and self built it ?
Once TT-400TP project succeeded on the latter way in 2011, they restarted the domestic Molniya project.
Look deep into TT-400TP project, Hong Ha shipyard director said
"Even foreign specialists are surprised that TT-400TP naval gun could shoot exact at first shot, while they need several adjustment before getting the perfect shot" That means there're different method of building applied, maybe in foreign facility they didn't adopt modular approach.
The director said "buying basic design costs only some hundred thousand dollars ( and Hong Ha must develop into details ) so that the domestic hull cost is about 1 million dollars at the time ( 2009-2011 )
Ba Son shipyard may get benefit from that experiment in Molniya project. The Molniya is basically different from TT-400TP by missiles and sensors only.
Molniya boats are only fruitful with domestic Kh-35 production.
Modular method XP in TT-400TP and gunboat, CIWS integrated
Missiles production and integrated sensors XP in Molniya
DN-2000 modular approach succeeded.
Let imagine what combined XP could be ?
>> this lead to
@Carlosa to think about transform DN-2000 to missile guided frigates. Yes they are prepared for that.
>> and modular 1000+ tonnage ship, also follow Carlosa.