The B-52H bomber can carry up to six AGM-129A missiles on each of two external pylons for a total of 12 per aircraft.
Originally, an additional 8 ACMs could be carried internally in the B-52 on Common Strategic Rotary Launchers, for a total of 20 per aircraft.
The B-1B bomber was also slated to carry the AGM-129A, but that plan was ended after the cessation of the Cold War.
The AGM-129A provides the B-52H bomber the ability to attack multiple targets without penetrating an air defense system.

An AGM-129A impacted and damaged two unoccupied trailers, part of a cosmic ray observatory operated by the University of Utah and Tokyo University, located in the "hazardous operations" area of the United States Army Dugway Proving Ground on December 10, 1997.
The AGM-129A was released over the Utah Test and Training Range from a B-52H bomber assigned to Minot Air Force Base, North Dakota.
The missile had flown for approximately 3.5 hours on its planned route and had fulfilled all test objectives prior to the mishap.
The missile was carrying an inert test payload.
Mission planners were unaware of the existence of the trailers.

The Air Force in 2008 maintained an arsenal of 1,140 AGM-86 ALCMs and 460 AGM-129 ACMs.
The B-52 is the only platform for these missiles.
The reductions also include all but 528 nuclear-armed ALCMs and are in part a result of the SORT/Moscow Treaty (2002) requirement to get below 2,200 deployed nuclear weapons by 2012, with the ACM chosen because it has reliability issues and higher maintenance costs.
In March 2007, despite a Service Life Extension program (SLEP) intended to extend its operational usefulness to 2030, the USAF made the final decision to decommission its entire inventory of AGM-129s with the last missile being destroyed in April 2012.
The B-52H bomber can carry up to six AGM-129A missiles on each of two external pylons for a total of 12 per aircraft. Originally, an additional 8 ACMs could be carried internally in the B-52 on Common Strategic Rotary Launchers, for a total of 20 per aircraft. The B-1B bomber was also slated to carry the AGM-129A, but that plan was ended after the cessation of the Cold War. The AGM-129A provides the B-52H bomber the ability to attack multiple targets without penetrating an air defense system.
An AGM-129A impacted and damaged two unoccupied trailers, part of a cosmic ray observatory operated by the University of Utah and Tokyo University, located in the "hazardous operations" area of the United States Army Dugway Proving Ground on December 10, 1997. The AGM-129A was released over the Utah Test and Training Range from a B-52H bomber assigned to Minot Air Force Base, North Dakota. The missile had flown for approximately 3.5 hours on its planned route and had fulfilled all test objectives prior to the mishap. The missile was carrying an inert test payload. Mission planners were unaware of the existence of the trailers.
The Air Force in 2008 maintained an arsenal of 1,140 AGM-86 ALCMs and 460 AGM-129 ACMs. The B-52 is the only platform for these missiles. The reductions also include all but 528 nuclear-armed ALCMs and are in part a result of the SORT/Moscow Treaty (2002) requirement to get below 2,200 deployed nuclear weapons by 2012, with the ACM chosen because it has reliability issues and higher maintenance costs. In March 2007, despite a Service Life Extension program (SLEP) intended to extend its operational usefulness to 2030, the USAF made the final decision to decommission its entire inventory of AGM-129s with the last missile being destroyed in April 2012.
AGM-129 ACM