The first revamped Peacekeeper warhead (MK21 re-entry vehicle) has been deployed on a Minuteman III ICBM, according to a Northrop Grumman release. (We now find that the first SERV deployment took place in October 2006. The Air Force says it has since fielded several—actual number withheld—more.) The feat required a “major revision” on the Minuteman software, under the Safety Enhanced Re-entry Vehicle program. USAF expects to have its entire 500-strong MMIII fleet upgraded by 2012, extending the service life of the ICBMs to 2020.
The Air Force overall reduced its size by 120 aircraft in fiscal year 2021, but kept about the same number of fighter, bomber and attack aircraft, according to data supplied by the service. The F-35 fleet saw the biggest increase while the B-1B bomber fleet saw the largest decline.