On June 9, 2003, about 1630 mountain standard time, a Robinson R22 Beta II, N727DD, rolled over during a low altitude hover near Deer Valley Airport (DVT), Phoenix, Arizona. Universal Helicopters, Inc., was operating the helicopter under the provisions of 14 CFR Part 91. The certified flight instructor (CFI) and student were not injured; the helicopter sustained substantial damage. The local instructional flight departed Scottsdale Airport (SDL), Scottsdale, Arizona, about 1600. Day visual meteorological conditions prevailed, and no flight plan had been filed. In a written statement, the CFI stated that this was the second instructional flight for the student. The CFI and student were hovering approximately 7 feet above ground level (agl). The CFI was in control of the cyclic and the student was in control of the antitorque pedals and the collective. During the hover, the helicopter rolled to the right and collided with the ground, coming to rest on its side. During wreckage recovery operations, the principal of Universal Helicopters observed a 3-foot-long drag mark in the dirt leading up to the helicopter's right skid. The helicopter was examined at Robinson Helicopter Company (RHC) in Torrance, California, by the National Transportation Safety Board investigator-in-charge (IIC) and a technical investigator from RHC. Control continuity was established with the cyclic, collective, and antitorque pedals and no preimpact control anomalies were noted. An aviation routine weather observation (METAR) was issued at 1622 for an airport about 6 miles away. Winds were reported from 170 at 9 knots, gusting to 17 knots.