Ballistic missile Nuclear weapons delivery

trident ii slbm launched royal navy vanguard-class submarine.

missiles using ballistic trajectory deliver warhead on horizon, @ distances of thousands of kilometers, in case of intercontinental ballistic missiles (icbms) , submarine-launched ballistic missiles (slbms). ballistic missiles exit earth s atmosphere , re-enter in sub-orbital spaceflight.

placement of nuclear missiles on low earth orbit has been banned outer space treaty 1967. also, eventual soviet fractional orbital bombardment system (fobs) served similar purpose—it deliberately designed deorbit before completing full circle—was phased out in january 1983 in compliance salt ii treaty.

an icbm more 20 times fast bomber , more 10 times fast fighter plane, , flying @ higher altitude, , therefore more difficult defend against. icbms can fired in event of surprise attack.

early ballistic missiles carried single warhead, of megaton-range yield. because of limited accuracy of missiles, kind of high yield considered necessary in order ensure particular target s destruction. since 1970s modern ballistic weapons have seen development of far more accurate targeting technologies, particularly due improvements in inertial guidance systems. set stage smaller warheads in hundreds-of-kilotons-range yield, , consequently icbms having multiple independently targetable reentry vehicles (mirv). advances in technology have enabled single missile launch payload containing several warheads. number of independent warheads capable of deployment ballistic missiles depends on weapons platform missile launched from. example, 1 d5 trident missile carried ohio-class submarine capable of launching 8 independent warheads, while typhoon has missiles capable of deploying 10 warheads @ time. mirv has number of advantages on missile single warhead. small additional costs, allows single missile strike multiple targets, or inflict maximum damage on single target attacking multiple warheads. makes anti-ballistic missile defense more difficult, , less economically viable, before.

missile warheads in american arsenal indicated letter w ; example, w61 missile warhead have same physics package b61 gravity bomb described above, have different environmental requirements, , different safety requirements since not crew-tended after launch , remain atop missile great length of time.