On December 8, 2003, at 1430 central standard time, a Robinson R22 Beta helicopter, N747LF, was substantially damaged during a hard landing in a field adjacent to David Wayne Hooks Memorial Airport (DWH), near Spring, Texas. The certified flight instructor (CFI) and student pilot were not injured. The helicopter was registered to and operated by Helicopter Services, Inc., of Spring, Texas. Visual meteorological conditions prevailed, and a flight plan was not filed for the 14 Code of Federal Regulations Part 91 instructional flight. The local flight originated from DWH approximately 1330. The CFI reported in the Pilot/Operator Accident Report (NTSB Form 6120.1/2) that after departure, they repositioned the helicopter to the practice area just west of the airport and started to perform a few basic maneuvers. The student pilot initiated a practice straight in autorotation on a southerly heading, "at 700 feet agl, and 70 knots." The CFI stated that the "approach angle and decent grew quite steep very quickly." As the "rotor rpm decayed to approximately 95% at an approximate altitude of 200 feet agl, the CFI initiated a go around by rolling on the throttle, lifting the collective, and moving forward on the cyclic while maintaining 60 knots as the helicopter continued to descend." He initiated a "hard flare to stop the rate of decent, but the decent was slowed, not stopped." The CFI leveled the helicopter, and executed a run on landing at approximately 30 knots. Subsequently, the helicopter landed hard on soft terrain, rolled over and came to rest on its left side. The CFI further reported that the left skid "hooked on an obstruction" prior to rolling over. Examination of the helicopter by an Federal Aviation Administration inspector, who responded to the accident site, revealed the aft six feet of the tail boom was separated, both main rotor blades were damaged, the left skid was separated from the fuselage, and the right landing skid was bent and remained attached. Examination of the accident site revealed there were no obstructions or obstacles near the main wreckage. A ground scar was found at the point of initial impact consistent with the length of the skid and was approximately once inch deep. The automated surface observing system at DHW reported at 1453, the wind from 180 degrees at 12 knots, gusting to 16 knots, visibility 10 statute miles, sky conditions overcast at 4,800, temperature 73 degrees Fahrenheit, dew point 57 degrees Fahrenheit, and an altimeter setting of 29.84 inches of Mercury.