The January 2006 START Treaty Memorandum of Understanding released today contains new data on the Bulava sea-launched ballistic missile (RSM-56 in the treaty). While dimentions and weight were listed in the previous MOU, this one has throwweight of the missile - 1150 kg, and the number of warheads the missile will be declared as carrying - six.

While the throwweight value is (appropriately) marked with "data will be confirmed by flight test results," the number of warheads seems to be final - Russia apparently intends to deploy the missile with six warheads.

The throwweight of little over one metric ton is comparable with that of the Topol-M missile - 1200 kg. But it is smaller than that of the latest generation of Soviet SLBMs - liquid-fuel R-29RM/SS-N-23 has 2800 kg (it carries four warheads) and solid-propellant R-39/SS-N-20 - 2550 kg (ten warheads). However, the SS-N-20 is significantly heavier - 90 tonnes against Bulava's 36.7. R-29RM is closer with 40.3 tonnes, but it is a liquid-fuel missile, which are usually more efficient.

Finally, below is a table that compares Bulava with C-4/Trident I missile, which is quite close to it in terms of launch weight and size.

Bulava Trident I
Number of stages 3 3
Length of assembled missile without front section, m 11.5 10.3
Maximum diameter of missile airframe (without stabilizers, raceways, protruding elements), m 2 1.88
Launch weight, tonnes 36.8 32.3
Total length of missile as a unit with launch canister (with front section), m 12.1 n/a
Length of launch canister body. m 12.1 n/a
Diameter of launch canister body (without protruding elements), m 2.1 n/a
First stage    
  Stage length. m 3.8 4.5
  Stage diameter, m 2 1.88
  Weight of fully loaded stage, tonnes 18.6 19.1
Second stage    
  Diameter (if different from first)


Third stage    
  Diameter (if different from first)


Declared number of warheads 6 8/6
Throwweight, kg 1150 1500