On October 10, 2004, at 1640 eastern daylight time, a Cessna 152, N68298, and a Cessna 172, N12625, were substantially damaged when they collided in-flight, on final approach to runway 01 at the Cincinnati West Airport (I67), Harrison, Ohio. The certificated commercial pilot in the Cessna 152 sustained serious injuries, the certificated commercial pilot in the Cessna 172 received minor injuries, and the private pilot-rated passenger in the Cessna 172 received serious injuries. Visual meteorological conditions prevailed and no flight plan was filed for either flight. The local personal flights were conducted under 14 CFR Part 91. According to both pilots, the purpose of the flights were to participate in a "spot landing" contest at the airport, which required the aircraft to land "on the numbers" of runway 01. The pilot of the Cessna 172 stated that after takeoff, he observed the Cessna 152 depart runway 01. The pilot continued in the left traffic pattern, believing that the Cessna 152 was well behind him. He turned onto final approach at 400 feet, extended 30 degrees of flaps and reduced the airspeed to 75 mph. While descending toward the runway, the pilot heard and felt a "thud." The airplane became unresponsive to control inputs, and continued in a descent. After impacting the ground, the airplane caught fire, and both occupants exited the cockpit. The pilot then realized he had experienced a collision with another airplane, and assisted the pilot of the Cessna 152 in exiting his airplane. The pilot of the Cessna 172 reported that he announced his position on the downwind, base, and final legs of the approach. He additionally stated that he only heard the pilot of the Cessna 152 announce his position once, on the downwind leg. The pilot of the Cessna 152 stated that he was too high and too fast during his first attempt at landing, and touched down well beyond the numbers. He performed a touch and go, and entered the left traffic pattern for his second attempt. The pilot announced his position on the UNICOM frequency, while on the downwind leg, and did not hear any other transmissions in the pattern. When he was abeam the numbers, he slowed the airplane to about 60-65 knots, turned onto the base leg "very close" to the runway, and turned final at 200-300 feet AGL. As the pilot turned final, he observed the top of the left wing and cockpit of the Cessna 172, and immediately felt the impact with the airplane. The pilot had no memory of the remainder of the flight. The pilot of the Cessna 152 reported that he did not check final approach for other aircraft prior to turning final, nor did he hear any other radio calls on the frequency. According to a witness, who observed the aircraft from his hangar at the airport, the Cessna 172 was on an approximate 1 mile final at 500 feet AGL, and a Cessna 152 was on a left base approximately 1 mile out, at 500-700 feet AGL. The Cessna 172 continued on a straight-in stabilized approach, while the Cessna 152 continued a left base, descending, stabilized approach. The flight paths converged approximately 1/4 mile from the end of runway 01, at 300 feet AGL. The right wing of the Cessna 152 appeared to contact the left wing of the Cessna 172, and both aircraft began a slow descending spiral, locked together, until they impacted a gravel pit, heading south. According to a Federal Aviation Administration inspector, the Cessna 172 sustained substantial damage to its right wing and fire damage to the fuselage section. The Cessna 152 sustained substantial damage to its left wing. The weather reported at Cincinnati/Northern Kentucky International Airport, about 13 miles to the south, at 1654, included 10 miles visibility, few clouds at 15,000 feet, and winds from 080 degrees at 9 knots. Review of Federal Aviation Regulation (FAR) 91.113(b) revealed: "General. When weather conditions permit, regardless of whether an operation is conducted under instrument flight rules or visual flight rules, vigilance shall be maintained by each person operating an aircraft so as to see and avoid other aircraft..." Review of FAR 91.113(g) revealed: "Landing. Aircraft, while on final approach to land or while landing, have the right-of-way over other aircraft in flight...When two or more aircraft are approaching an airport for the purpose of landing, the aircraft at the lower altitude has the right-of way, but it shall not take advantage of this rule to cut in front of another which is on final approach to land or to overtake that aircraft." According to the Airman Information Manual (AIM), paragraph 4-1-9(h), UNICOM Communications Procedures, "In communicating with a UNICOM station, the following practices will help reduce frequency congestion, facilitate a better understanding of pilot intentions, help identify the location of aircraft in the traffic pattern, and enhance the safety of flight:...(e) Report on downwind, base, and final approach."