A letter report issued by the Government Accountability Office with an abstract that begins "Over the past several decades, the Army and Marine Corps have increased their use of simulation-based training--simulators and computer-based simulations. Historically, the aviation communities in both services have used simulators to train servicemembers in tasks such as takeoffs, and emergency procedures that could not be taught safely live. In contrast, the services' ground communities used limited simulations prior to 2000. However, advances in technology, and emerging conditions in Iraq and Afghanistan have led to increased use of simulation-based training in the ground forces. For example, in response to increases in vehicle rollovers, both services began using simulators to train servicemembers to safely evacuate vehicles. The services are also collaborating in the development of some simulation-based training devices. For instance, according to Marine Corps officials, the service reused 87 percent of the Army's Homestation Instrumentation Training System's components in its own training system, achieving about $11 million in cost avoidance and saving an estimated 7 years in fielding time. The services are also taking steps to better integrate live and simulation-based training, developing technical capabilities to connect previously incompatible simulation-based training devices. The Army's capability is now …