HISTORY OF FLIGHT On November 6, 1993, around 1125 Pacific standard time, a Boeing (Stearman) PT-13D, N14FR, and a Cessna 172H, N2718L, collided during landing rollout at the Half Moon Bay Airport (HAF) near Half Moon Bay, California. The Stearman was operated by a commercial pilot. The Cessna was operated by a private pilot. Visual meteorological conditions prevailed at the time of the personal flights, and no flight plans were filed. Both airplanes were substantially damaged and neither pilot was injured. The Stearman's flight originated from Chowchilla, California, at 0945. The Cessna's flight originated from San Carlos, California, at 1115. The Stearmans' Flight On November 16, 1993, the daughter of the Stearman pilot verbally reported to the National Transportation Safety Board that she had been flying with her father on the accident date, but had been in another Stearman. In fact, she had been in the lead Stearman of a "flight of two." By prior arrangements, both she and her father had flown from the Flanagan Ranch's airstrip, in Chowchilla, to HAF. She stated that her Stearman was radio equipped; her father's was not. Regarding their preflight planning, she acknowledged that she was unaware that a temporary air traffic control tower was in operation at HAF. In her father's "Aircraft Accident Report", NTSB Form 6120.1, the daughter made the following statement regarding preflight planning: "A call to FSS was made...[by her, and she was] unable to get through to briefer." She verbally reported to the Safety Board that she had waited for about 5 minutes for Flight Service to answer while listening to a recording. The daughter recalled that as she and her father approached HAF, she radioed the field on UNICOM and was informed that a tower was in operation. She then radioed the tower, informed the controller that she was a "flight of two" and was instructed to report downwind for runway 30. There was considerable radio traffic on the frequency and congestion in the pattern. While in the downwind leg, she observed that her father's airplane was no longer next to her and, thereafter, she lost sight of it. She did not inform the controller that she had lost visual contact with her father's airplane or that his airplane was not radio equipped. In conclusion, she stated that she landed in accordance with her air traffic clearance on runway 30 and, in her opinion, no emergency condition existed regarding the operation of her or her father's airplane. According to the daughter, her father had lost sight of her while approaching the traffic pattern. The daughter reported that her father believed runway 12 was active based upon: (1) the presence of other traffic; and (2) the position of the wind sock which indicated that a light wind was from the southeast. The Federal Aviation Administration (FAA) local controller, who had been on duty at the time of the mishap, reported to the Safety Board that he had been quite busy with handling the approximately nine airplanes in the pattern. He never heard any radio call from any "flight of two" airplanes, and he never observed any such flight in the pattern. The controller further reported that he recalled issuing a landing clearance to a biwing airplane (the daughter's Stearman). The clearance was to land on runway 30. The controller also stated that, thereafter, he recalled issuing a similar clearance to the (accident) Cessna. The controller stated that his attention was then directed toward other air traffic. He did not observe the Cessna roll out on runway 30, and he did not observe the second biwing airplane approach, land on runway 12, or collide with the Cessna. The Cessna's Flight The Cessna pilot reported to the Safety Board that prior to taking off he had learned that a temporary air traffic control tower was in use for an air show at the airport. Accordingly, approaching the airport he contacted the tower and received landing instructions. The Cessna pilot stated that he landed on runway 30 in accordance with the air traffic control clearance he had received. He recalled that the wind sock located near the approach end of the runway indicated the wind was from the south at 3 to 4 knots. The Cessna pilot further reported that he first observed the Stearman during his own rollout on runway 30. He stated that he did not hear any air traffic communications regarding the presence of the Stearman which was attempting to approach and land in an opposite direction. The Cessna pilot stated that he attempted to maneuver away from the rapidly and head-on approaching Stearman by veering off the runway. However, as he turned right the Stearman turned left, and he was unable to avoid the collision. The left wings of both airplanes collided with each other and broke. The two FAA air traffic controllers who were on duty in the temporary tower reported that, at the time of the mishap, the wind favored use of runway 30. The wind sock, located near the center of the airport, indicated that the wind was from about 300 degrees at a maximum speed of 10 knots. Runway 30 was the active runway and had been used continuously since the temporary tower commenced operation at 0900. The controllers further indicated that the Cessna had been issued a clearance to land on runway 30. No landing clearance had been issued to the accident Stearman. ACCIDENT SITE INFORMATION The accident occurred an estimated 1,300 feet north of runway 30's landing threshold in a clear area to the north (right) side of the runway. The temporary control tower was located an estimated 600 feet from the collision site. (The distance estimates were based upon FAA and pilot supplied data, and they may be in error by plus or minus 200 feet.) PERSONNEL INFORMATION Pilot of Lead Stearman in the Accident Flight of Two The pilot, age 38, held an airline transport pilot certificate, No. 566725393, and a flight instructor certificate. She was type rated in Boeing 737, 757, and 767 turbojet airplanes, and was employed as an airline pilot. The pilot's last aviation medical certificate was issued in the First Class, in May of 1993, at which time she reported having over 7,000 hours of flight time. Pilot of the Accident Stearman The pilot, age 81, held commercial pilot and flight instructor certificates. He had over 4,000 hours of flight time, and he had provided dual flight instruction in the accident model of airplane for over 2,800 hours. The pilot's last aviation medical certificate was issued in the Third Class in May of 1992 and, during the 90-day period preceding the accident, he had flown the accident model airplane for 4.4 hours. Pilot of the Accident Cessna The pilot, age 53, held a private pilot certificate. He had 354.6 hours of flight time, all of which were in the accident model of airplane. The pilot's last aviation medical certificate was issued in the Third Class in July of 1992. During the 90-day period preceding the accident, the pilot reported having flown the accident model airplane for 15.9 hours. ADDITIONAL INFORMATION Prior to the accident, a Notice to Airman (NOTAM) had been issued which indicated, in pertinent part, that a temporary control tower would be in operation on November 6, starting at 0900. Operations would terminate after noon. According to the FAA air traffic controllers, when the temporary "suitcase" tower was set up at HAF, no provision was made for recording any of their air traffic communications. FAA management verbally reported to the Safety Board that no recording equipment was contained in the standard package used in "suitcase" towers.