On February 12, 2004, about 1155 mountain standard time, a MDHI 369FF, N630N, experienced a main rotor blade strike to the tail boom following a hard landing at Falcon Field Airport (FFZ), Mesa, Arizona. The helicopter was owned and operated by MDHI under the provisions of 14 CFR Part 91. The certified flight instructor and passenger receiving a flight demonstration were not injured; the helicopter sustained substantial damage. The local instructional flight departed FFZ about 1125. Visual meteorological conditions prevailed, and a company flight plan had been filed. In a written statement, the pilot reported that he had successfully completed four full-touchdown practice autorotations. On the fifth attempt, the entry and decent were normal. Before touching down, about 2 feet above ground level, he raised the collective in an effort to cushion the landing. The helicopter encountered a gust of wind and the nose turned 45 degrees to the left. He applied right pedal pressure to counteract the sudden drift, but was unable to get the helicopter back on centerline. During touchdown, the pilot lowered the collective about halfway in an effort to reduce ground slide, while at the same time inputting a small amount of forward cyclic pressure to avoid the main rotor contacting the tail boom. The helicopter landed hard and skid about 4 feet until it came to rest without incident. A few seconds later, the pilot heard a loud noise. The main rotor blades had collided with the tail boom. The pilot did not report any mechanical problems with the helicopter prior to the accident. An aviation routine weather report (METAR) for FFZ at 1145, reported winds from 040 degrees at 10 knots and visibility at 50 statute miles.