The airplane was substantially damaged during a hard landing at approximately 1645 Mountain time. Visual conditions prevailed; the Private pilot and three passengers were not injured. The pilot later said he made his final approach to 85 KIAS with two notches of flap. About 150 yards from the runway threshold, the airplane fell and began to sink excessively in a nose-high attitude. He attributed this to windshear. The airplane landed hard and bounced. A pilot-witness said the wind was about 5-10 knots down the runway with no gusts. The accident airplanes approach was low and with a high power setting. When the airplane touched down, it rolled forward on its nose wheel. He heard power applied and he said the gear started to come up.