The non-certificated pilot and his passenger took off from the turf strip in the experimental light sport Quicksilver MXL II, and flew for a short time before returning for a landing. The airplane touched down normally, and the pilot intentionally lifted off again. The pilot climbed to an altitude of approximately 50 feet above the runway, where he pitched the nose down to land again. The airplane attitude and flight path was "too steep to flare," and the pilot was unable to prevent the airplane from impacting the runway, which resulted in substantial airplane damage. The tubular frame of the airplane was fractured and bent in multiple locations. The pilot, seated in the left seat, was uninjured. His passenger, seated in the right seat, incurred serious injuries. The winds were calm, and daylight conditions existed at the time of the accident. The pilot did not report any mechanical problems on the accident flight.