The pilot reported that during landing at dusk, and into the setting sun, he observed "flat light" conditions. The private dirt airstrip increased in gradient as he landed to the west. About 75 knots airspeed, the pilot increased the flaps, attempted to bleed off airspeed, and touched down. The airplane landed hard, "because I literally did not see it coming." The nose gear collapsed, and the airplane nosed over.
The airplane sustained substantial damage to the right wing, the lower fuselage and the empennage.
The pilot reported that there were no mechanical malfunctions or failures with the airplane that would have precluded normal operation.