Three F/A-18 Hornets are hot refueled at Roswell Industrial Air Center, N.M., after an Exercise Roving Sands '97 mission over the New Mexico desert on April 22, 1997. More than 20,000 service members from all branches of the armed forces of the U.S., Canada, Germany, and the Netherlands are participating in Exercise Roving Sands '97. The exercise is designed to refine their skills in operations using an integrated air defense network of ground, missile and radar early warning systems combined with tactical fighter and bomber aircraft operating in a simulated high-threat environment.