At Boeing's Rotorcraft site in Mesa, Arizona, the optionally manned Little Bird is shown in a key role in validating the Block III capabilities for the Apache. The light helicopter, also developed by the Mesa site, was acting as a surrogate for the U. S. Army’s Extended Range Multi-Purpose Warrior UAV. The Little Bird was testing the capability to control the unmanned aircraft from the Apache cockpit. Level of Interoperability (LOI) 4 control of the UAV, its sensors and weapons is one part of the Block III upgrade that Army officials say will change helicopter combat operations completely.