On July 5, 1993, about 1535 hours Pacific daylight time, a Cessna 172- K, N79034, crashed during a banner towing operation at Zamperini Field, Torrance, California. The airplane was being operated as a visual flight rules (VFR) local area flight when the accident occurred. The airplane operated by Star Ads Inc., was substantially damaged. The certificated commercial pilot, the sole occupant, received serious injuries. Visual meteorological conditions prevailed. The flight originated from Torrance about 1530. The pilot reported that he departed runway 29R and entered the traffic pattern to make an aerial pickup of an advertising banner. Following the pickup of the banner from the end of runway 29R, the pilot began a climb to lift the banner off the ground. During the climb, the body of the banner folded forward toward the airplane and the head of the banner began to descend. The airplane began rolling from side to side and about 150 feet above the ground, the pilot jettisoned the banner. The airplane was in a steep, nose high attitude, and the airspeed was decreasing. The pilot reported that he lowered the nose of the airplane in an attempt to recover from a stalled condition. Witnesses reported that the airplane was observed to descend in a steep nose down attitude while in a slight left turn. The airplane struck the ground on the north side of runway 29R. The operator reported that wind conditions at the airport had recently shifted prior to the accident to favor runway 29. He indicated that the coastal hills located west of the airport are a source of turbulence and windshear. The operator's latest FAA Certificate of Waiver for banner towing operations was issued on April 30, 1993, and is valid from May 1, 1993, to April 30, 1994. Examination of the airplane revealed that the outboard leading edge of the left wing was deformed aft and up. The right wing was undamaged. The flaps were extended about 16 degrees. The empennage was bent aft of the cabin. The tailcone bulkhead was fitted with a single banner- towing release hook which was in the released position. The inboard trailing edges of both wings, forward of the flaps, were opened and exhibited hydraulic deformation signatures. The pilot holds a commercial pilot certificate with airplane single engine land, multi-engine land, and instrument airplane ratings. The most recent first class medical certificate was issued to the pilot on August 27, 1992 and contained no limitations. According to the pilot/operator report submitted by the pilot, his total aeronautical experience consists of about 707.8 hours, of which 217.1 were accrued in the accident aircraft make and model. In the preceding 90 and 30 days prior to the accident, the report lists a total of 27.6 and 6.2 hours respectively flown. The pilot received instruction and an endorsement for banner towing operations on July 19, 1991. The airplane had accumulated a total time in service of 2,060.3 flight hours. Examination of the maintenance records revealed that the most recent annual inspection was accomplished on March 19, 1993, 91 flight hours before the accident. The engine had accrued a total time in service of 2,060.3 hours of operation. The maintenance records note that a major overhaul was accomplished on November 14, 1973, 1,355.5 hours of operation before the accident. An annual inspection was accomplished on the date specified above for the airframe. The closest official weather observation station is located at Torrance. At 1535 hours, the time of the accident, a surface observation was reporting in part: Sky condition and ceiling, clear; visibility, 10 miles; temperature, 78 degrees F; dew point, 59 degrees F; wind, 210 degrees at 10 knots; altimeter, 29.84 inHg. According to the Torrance Airport records of surface weather observations, a surface observation at 1346 hours indicated that the wind was from 150 degrees at 8 knots. A wind shift was reported at 1425 hours, indicating that the wind was from 240 degrees at 7 knots. The last surface observation before the accident was taken at 1446 hours. At that time the wind was from 240 degrees at 9 knots. Review of the air-ground radio communications tapes maintained by the FAA at the Torrance Tower facility revealed that after the accident airplane departed and before the banner was picked up, the pilot was given a wind advisory by the local controller who stated: "Wind variable from the south to the north at five". Zamperini Field is equipped with two parallel hard surfaced runways on a 110 to 290 degree magnetic orientation. Runway 29R is 5,000 feet long by 150 feet wide.