China ICBM/SLBM, nuclear arms thread

FairAndUnbiased

Brigadier
Registered Member
It is funny that DOD went from "they never deploy more than 50 DF-31 over two decades." to "Massive DF-31 silo so it can't reach Florida."

Also the silo diameter is around 4.3 to 4.5 meters, enough room for a variety of ICBM in theory.


Silo lid is around 4.5m if the width of truck is 2.5m based on recent satellite image.

For comparison, MM silo has a diameter of 3.7m and enough for a 2.34m Peacekeeper when cold launched. Generally a smaller silo is cheaper and more blast-resist than a larger silo, so I personally believe PLARF will load heavy ICBM into them instead of 2m-class DF-41, which a 4.3m silo is an overkill for ICBM in its size.
View attachment 109173
or it could be a flexible arrangement of DF-5s (3.3 m) and DF-41 so there is a mix of heavy and light. We know the maximum cost of the DF-5 based on LM-2 costs with a small discount for 3rd stage being exchanged for the bus.
 

ACuriousPLAFan

Colonel
Registered Member
It seems the estuary of the Tumen river could potentially be a good location for China' SSBN base. What difficulties have stopped China from building a base there?
Because the Chinese territory does not extend to the Tumen estuary. The Tumen estuary is split between North Korea and Russia.

Besides, pretty much the entire length of the Tumen River is shallow - In fact, too shallow for nuclear submarines to operate safely.
 
Last edited:

Kalec

Junior Member
Registered Member

or it could be a flexible arrangement of DF-5s (3.3 m) and DF-41 so there is a mix of heavy and light. We know the maximum cost of the DF-5 based on LM-2 costs with a small discount for 3rd stage being exchanged for the bus.
Not quite possible to place DF-5 in solid silo. They don't have a exhaust tunnel, which makes it impossible for DF-5 to conduct a hot launch. DF-5 needs a 8m silo as it is one of the largest ICBMs in term of diameter, probably second only to R-7.

Also as the chart shows, 4.3m silo is quite roomier in modern standard and it generally needs to be made as small as possible to make itself harder. I suspect there is no need to make it 4.3m unless there exists a heavy ICBM to put them in. It could be made for flexible deployment in the future, giving the room if there is a demand to upgrade from DF-41.

SiloMissileSilo diameterMissile diameter
Type IIIASS-78.3m3m
Type IIIBSS-87.8m2.68m
Type IIIFSS-185.8m - 6m
4.8m at its top
3.05m
Type IIIG SS-194m - 4.2m2.5m
American siloMinuteman (hot launch)
Peacekeeper (cold launch)
3.7mMinuteman 1.68m
Peacekeeper 2.34m
Chinese solid siloN/A4.3mN/A
Chinese liquid siloDF-5 series8m3.35m
 

Maikeru

Captain
Registered Member
DF41 presumably made a lot of design and cost compromises to keep it road mobile, it doesn't make a lot of sense to me to silo-base it when a more powerful and cheaper non-mobile ICBM could be used.

I heard on here about a rumoured DF-45 as the missile for the new silos. Can anyone confirm?
 

gelgoog

Brigadier
Registered Member
Solids are typically harder to do the larger the diameter they have. Most of the large diameter missiles on that table are liquid rockets.
Making a solid rocket engine is kind of like pouring concrete. You have to mix the propellant, and then pour it into the castings, and you cannot have any cracks or cavities as a result of the process or the rocket will basically blow itself up once you ignite it.

Then there is the fact solid rockets use much denser fuel than liquid rockets, and cannot be fueled on site. Quite often because of weight limits very large solid rockets are transported in segments to the launch site and assembled there. But segmented solids have more failure modes. For example just like in the Challenger Space Shuttle disaster the O-rings connecting the solid segments can erode and the rocket can blow itself up while the rocket is in flight.
 

vincent

Grumpy Old Man
Staff member
Moderator - World Affairs
Solids are typically harder to do the larger the diameter they have. Most of the large diameter missiles on that table are liquid rockets.
Making a solid rocket engine is kind of like pouring concrete. You have to mix the propellant, and then pour it into the castings, and you cannot have any cracks or cavities as a result of the process or the rocket will basically blow itself up once you ignite it.

Then there is the fact solid rockets use much denser fuel than liquid rockets, and cannot be fueled on site. Quite often because of weight limits very large solid rockets are transported in segments to the launch site and assembled there. But segmented solids have more failure modes. For example just like in the Challenger Space Shuttle disaster the O-rings connecting the solid segments can erode and the rocket can blow itself up while the rocket is in flight.
The motor has a diameter of 11.48 foot (3.5 meters)1 and a maximum thrust of 1,00,000 pounds-force (500 tons) is powered by 330,000 pounds (150 tons) of solid fuel.
Please, Log in or Register to view URLs content!
 

Kalec

Junior Member
Registered Member
The motor has a diameter of 11.48 foot (3.5 meters)1 and a maximum thrust of 1,00,000 pounds-force (500 tons) is powered by 330,000 pounds (150 tons) of solid fuel.
Please, Log in or Register to view URLs content!
Yeah it was made by the same department who manufactures China's ICBM. The engine you mentioned has a more detailed specification
in a journal written by former leader of the department, Tian Weiping, in 2020.
固体火箭发动机需要实现高能高性能,通过创新固体火箭发动机设计理念、持续研究新型高能推进剂和先进的功能材料、不断提升工艺和制造水平,固体火箭发动机能量水平和质量比分别实现305~310 s、0.95,满足战略领域对固体火箭发动机的需求。
为满足未来战术导弹对固体火箭发动机的性能水平和使用适应性需求,固体火箭发动机还应该具有高性能强适应特点,通过采用先进的设计分析技术、推进剂以及复合材料技术,在提升发动机性能同时,满足高低温环境、大过载、低易损等特殊要求,固体火箭发动机能量水平和质量分别比达到265 s、0.90。
对于航天运载与助推领域,大型化是固体火箭发动机的发展目标。一方面,发展先进整体式大型固体火箭发动机,突破纤维壳体、大型柔性喷管等技术,实现发动机直径3.5 m、推力500 t、工作时间120 s、质量比≥0.93,为全固体运载火箭提供高性能基础级动力; 另一方面,发展大型金属壳体分段式固体火箭发动机,突破分段燃烧室对接、大流量高可靠矢量喷管等技术,实现发动机直径3.5 m、5段式、推力1500 t、工作时间120 s、质量比0.86,为重型运载火箭提供高可靠助推动力
Rough translation:

"The Isp and mass ratio of solid rocket motors should achieve 305-310s and 0.95, respectively, to meet the demand for solid rocket motors in strategic fields.

In order to meet the performance level and adaptability demand of future tactical missiles for solid rocket motors,..., it should have its Isp and mass ratio to reach 265 s, 0.90.

For the field of space launch vehicle and booster, the development of advanced integral large solid rocket motors, breakthroughs in fiber shell, large flexible nozzle and other technologies to achieve engine diameter 3.5 m, thrust 500 t, working time of 120 s, mass ratio ≥ 0.93 and a solid motor of 3.5 m, 5-segment, thrust 1500 t, working time 120 s, mass ratio 0.86 for heavy launch vehicles."

The 500t motor has conducted its hot test in late 2021 and the strategic motor could have been tested already sometime between 2020 and 2021 but not made public for the obvious reason.

It is very impressive that if the motor has a vacuum Isp over 305s and mass ratio over 0.95, and if not mistaken it could be the most advanced solid motor ever made.
 

FairAndUnbiased

Brigadier
Registered Member
DF41 presumably made a lot of design and cost compromises to keep it road mobile, it doesn't make a lot of sense to me to silo-base it when a more powerful and cheaper non-mobile ICBM could be used.

I heard on here about a rumoured DF-45 as the missile for the new silos. Can anyone confirm?
its not particularly bigger than Topol-M, and smaller than Hwasong-15 and Hwasong-17. It makes no more design and cost compromises than any other missile of its class. Topol-M is also silo based.
 

gelgoog

Brigadier
Registered Member
DF-41 is allegedly heavier than Yars and larger and heavier than Minuteman-III.

When you consider that DF-41 probably uses technologies not available when Minuteman-III was originally designed like carbon composite materials in the rocket construction and possibly higher density propellants, it likely has way more throw weight and range. The Minuteman-III missile is utterly obsolete at this point. And yet it is still the US silo based missile deterrent.

DF-41 is large enough to put on silos. Like @FairAndUnbiased said the Topol-M has a similar size and is also silo based. As is Yars.
 

ChongqingHotPot92

Junior Member
Registered Member
It is funny that DOD went from "they never deploy more than 50 DF-31 over two decades." to "Massive DF-31 silo so it can't reach Florida."

Also the silo diameter is around 4.3 to 4.5 meters, enough room for a variety of ICBM in theory.


Silo lid is around 4.5m if the width of truck is 2.5m based on recent satellite image.

For comparison, MM silo has a diameter of 3.7m and enough for a 2.34m Peacekeeper when cold launched. Generally a smaller silo is cheaper and more blast-resist than a larger silo, so I personally believe PLARF will load heavy ICBM into them instead of 2m-class DF-41, which a 4.3m silo is an overkill for ICBM in its size.
View attachment 109173
You are suggesting massive production of DF-5 series using storable liquid fuel?
 
Top