The US Government Accountability Office (GAO) recently released its sixth annual assessment on major defense system acquisitions. It states that, "Since 2000, the Department of Defense (DOD) has roughly doubled its planned investment in new systems from $790 billion to $1.6 trillion in 2007, but acquisition outcomes in terms of cost and schedule have not improved. Total acquisition costs for major defense programs in the fiscal year 2007 portfolio have increased 26 percent from first estimates, compared with 6 percent in 2000. Programs have also often failed to deliver capabilities when promised."
One of the reasons the cost increases is software.
"Programs continue to have difficulty managing software development for weapon systems. Roughly half of the programs that provided us data had more than a 25 percent growth in their expected lines of code since starting system development."
The report says that programs like Future Combat Systems (FCS) has seen code increases of 300% while others like the Expeditionary Fighting Vehicle program have experienced major software reliability problems that have contributed to their cost and schedule delays.