▁weapons ▁by ▁ 2 0 1 2 , ▁with ▁the ▁AG M - 1 2 9 ▁AC M ▁chosen ▁for ▁dispos al ▁because ▁it ▁has ▁reli ability ▁problems ▁and ▁high ▁maintenance ▁costs . ▁ ▁Even ▁with ▁the ▁S LE P ▁( service ▁life ▁extension ▁program ), ▁the ▁remaining ▁AG M - 8 6 s ▁were ▁to ▁reach ▁their ▁end ▁of ▁service ▁by ▁ 2 0 2 0 , ▁leaving ▁the ▁B - 5 2 ▁without ▁a ▁nuclear ▁mission . ▁However , ▁in ▁ 2 0 1 2 , ▁the ▁US AF ▁announced ▁plans ▁to ▁extend ▁the ▁useful ▁life ▁of ▁the ▁miss iles ▁until ▁at ▁least ▁ 2 0 3 0 . ▁ ▁To ▁replace ▁the ▁A LC M , ▁the ▁US AF ▁planned ▁to ▁award ▁a ▁contract ▁for ▁the ▁development ▁of ▁the ▁new ▁Long - Range ▁Stand - Off ▁( LR SO ) ▁weapon ▁in ▁ 2 0 1 5 . ▁Un like ▁the ▁AG M - 8 6 , ▁the ▁L R SO ▁will ▁be ▁carried ▁on ▁multiple ▁aircraft , ▁including ▁the ▁B - 5 2 , ▁the ▁B - 2 ▁Spirit , ▁and ▁the ▁North rop ▁Gr um man ▁B - 2 1 . ▁Like ▁the ▁AG M - 8 6 , ▁the ▁L R SO ▁can ▁be ▁armed ▁with ▁either ▁a ▁conventional ▁or ▁nuclear ▁war head . ▁ ▁The ▁L R SO ▁program ▁is ▁to ▁develop ▁a ▁weapon ▁that ▁can ▁pen et rate ▁and ▁surv ive ▁integrated ▁air ▁defense ▁systems ▁and ▁pro sec ute ▁strateg ic ▁targets . ▁ ▁Both