A significant development in this area is an IEEE data protocol standard for distributed interactive simulations. This standard allows the distributed simulation to include not only aircraft, but also land-based vehicles and ships. Many aspects of combat operations are very hazardous, and they become even more dangerous if the combatant seeks to improve his performance. Prime examples of this principle are firing weapons and performing reconnaissance. To perform either of these tasks well takes time, and this is usually time when the combatant is exposed to hostile fire.
Some smart weapons are autonomous, while others are remotely controlled after they are launched.
This allows the shooter and weapon controller to launch the weapon and immediately seek cover, thus decreasing his exposure to return fire. In the case of RPVs, the person who controls the vehicle not only has the advantage of being in a safer place, but the RPV can be made smaller than a vehicle that would carry a man, thus making it more difficult for the enemy to detect. In a dynamic combat environment, it is imperative to supply the pilot or tank commander with as much of the necessary information as possible while reducing the amount of distracting information. With the HUD, the pilot never has to look down at his instruments. When the HUD is coupled with the aircraft's radar and other sensors, a synthetic image of an enemy aircraft can be displayed on the HUD to show the pilot where that aircraft is, even though the pilot may not be able to see the actual aircraft with his unaided eyes.