On June 6, 1997, at 1325 Pacific daylight time, a Cessna 210D, N3908Y, registered to the Boeing Employees Flying Association, and being flown by a private pilot, was substantially damaged during a gear up landing at the Renton Municipal airport, Renton, Washington. The pilot was uninjured. Visual meteorological conditions existed and no flight plan had been filed. The flight, which was a ferry flight, was to have been operated under 14CFR91, and originated from Auburn, Washington, approximately 1035. The pilot reported that upon arriving in the Renton area he was unable to lower the landing gear. After repeated unsuccessful attempts to lower the gear, the aircraft was landed gear up on runway 15. The pilot reported that the aircraft had just come out of a gear check at the Auburn airport. A Federal Aviation Administration Inspector from the Seattle, Washington, Flight Standards District Office, inspected the airplane, and reported that the landing gear hydraulic power pack failed internally, and would not allow hydraulic pressure to the down position (refer to ATTACHMENT I). The pilot was sent a National Transportation Safety Board Pilot/Operator Aircraft Accident Report Form 6120.1/2, on June 6, 1997, and again on September 10, 1997. The first form was not returned and the second, which was sent certified, was unclaimed (refer to ATTACHMENT II). The pilot was subsequently contacted via telephone and assured the NTSB's Northwest Regional Office that he would mail a Xerox copy of the form which he claimed to have completed. As of February 17, 1998, the form had not been received.