The flight examiner stated that the accident occurred while administering a sport pilot airplane check ride to the student pilot. During the preflight briefing, he advised the student pilot that he, the student, would be the pilot in command under FAR 61.47(b) for the practical test. He indicated that on the third landing, which was a simulated soft field landing, the student pilot flared too high. He said that he told the student pilot to add power and conduct a go-around. Shortly thereafter, the airplane collided with the ground, and veered off to the left of the runway. The student pilot reported that during the landing flare the airplane did not touchdown but, instead, began to climb. He said that he added more power in an attempt to recover from a hard landing. Subsequently, the flight examiner yelled, "add more power and go around," at that point, the airplane collided with the runway. The student pilot did not report any mechanical or flight control anomalies prior to the accident. Examination by a FAA inspector revealed that the firewall and fuselage were buckled.