"Costs for the Advanced Extremely High Frequency satellite program grew 118 percent and its first satellite was launched more than 3.5 years late," the report stated. "Costs for the Space Based Infrared System grew nearly 300 percent and its scheduled launch was delayed roughly nine years."
Ground system delays have been so lengthy that satellites sometimes spend years in orbit before key capabilities can be fully utilized. The launch of the first GPS satellite has been delayed almost four years because of technical problems, the GAO noted.
"Development challenges for the satellite’s ground system have resulted in delays so significant that the Air Force has started two other ground system efforts as workarounds to mitigate risk of delayed GPS capability," the report said.
It remains unclear how the Defense Department will overcome a number of challenges that risk the timely fielding of upgraded GPS user equipment for soldiers, the GAO cautioned.