A letter report issued by the Government Accountability Office with an abstract that begins ""

A letter report issued by the Government Accountability Office with an abstract that begins "GAO identified 15 key aerostat and airship efforts that were underway or had been initiated since 2007, and the Department of Defense (DOD) had or has primary responsibility for all of these efforts. None of the civil agency efforts met GAO's criteria for a key effort. Most of the aerostat and airship efforts have been fielded or completed, and are intended to provide intelligence, surveillance, and reconnaissance (ISR) support. The estimated total funding of these efforts was almost $7 billion from fiscal years 2007 through 2012. However, funding estimates beyond fiscal year 2012 decline precipitously for aerostat and airship efforts under development, although there is an expectation that investment in the area will continue."