Mr.Sengupta's ATV article (which has been reproduced elsewhere on this site) puts the ATV's maximum displacement at 7000 tonnes submerged, states that any future SSGN or SSBN based on the ATV would displace 7500 tonnes and 9000 tonnes respectively.
Now, the ATV is a tech demonstrators so its not carrying the full systems needed for SSBN operations. In particular, it wont be carrying any weapons.
The book Strategic Anti-submarine warfare and naval strategy by Tom Stefanick gives the following weight distribution for early nuclear submarines:
Hull (shell,frames and bulkhead) 40-45%
Systems and installed equipment 18-24%
machinery 15-17%
Arms 10-12%
Fuel, feed water, lubrication 2.5-3%
Crew,provisions and fresh water 1-2%
Reserve displacement 2-2.5%
Solid ballast 2-2.5%
The ohio SSBN has the following displacement distribution:
Weapons and Weapon control: 14%
Command and control: 6%
Machinery: 22%
Configuration (hull,tanks,ballast etc): 58%
Now since the ATV is not carrying weapons at the moment, her displacement should be down by say 15% from a proper SSBN based on the ATV. Which should theoretically mean that if we multiply the 7000 tonnes by 1.15 (=8050 tonnes) we should get the ATV displacement when she is an SSBN. But the articles states that the future SSBN based on the ATV will displace 9000 tonnes, which is an extra 1000 tonnes from out theoretical estimate. Where is that extra tonnage coming from? Which systems do you think i missed? Or will the future SSBN's weapons be considerably heavier than any SLBMs the indians might have now. Will appreciate your help on this.
Perhaps the article is incorrect about the ATV's double hull configuration or maybe the ATV used HY-150 or HY130 instead of HY-80 as the higher yield steel would considerably reduce the ATV's weight.
Also, Does anyone know which High Yield steel the Akula's hull is made of? I once read somewhere that it was HY-150 but i cant seem to confirm this. Any help on this? Thanks!
Now, the ATV is a tech demonstrators so its not carrying the full systems needed for SSBN operations. In particular, it wont be carrying any weapons.
The book Strategic Anti-submarine warfare and naval strategy by Tom Stefanick gives the following weight distribution for early nuclear submarines:
Hull (shell,frames and bulkhead) 40-45%
Systems and installed equipment 18-24%
machinery 15-17%
Arms 10-12%
Fuel, feed water, lubrication 2.5-3%
Crew,provisions and fresh water 1-2%
Reserve displacement 2-2.5%
Solid ballast 2-2.5%
The ohio SSBN has the following displacement distribution:
Weapons and Weapon control: 14%
Command and control: 6%
Machinery: 22%
Configuration (hull,tanks,ballast etc): 58%
Now since the ATV is not carrying weapons at the moment, her displacement should be down by say 15% from a proper SSBN based on the ATV. Which should theoretically mean that if we multiply the 7000 tonnes by 1.15 (=8050 tonnes) we should get the ATV displacement when she is an SSBN. But the articles states that the future SSBN based on the ATV will displace 9000 tonnes, which is an extra 1000 tonnes from out theoretical estimate. Where is that extra tonnage coming from? Which systems do you think i missed? Or will the future SSBN's weapons be considerably heavier than any SLBMs the indians might have now. Will appreciate your help on this.
Perhaps the article is incorrect about the ATV's double hull configuration or maybe the ATV used HY-150 or HY130 instead of HY-80 as the higher yield steel would considerably reduce the ATV's weight.
Also, Does anyone know which High Yield steel the Akula's hull is made of? I once read somewhere that it was HY-150 but i cant seem to confirm this. Any help on this? Thanks!