On March 31, 1995, at 1030 hours Pacific standard time, an Aeronca 7AC, N1937E, collided with the terrain while executing an emergency landing at El Cajon, California. The emergency landing resulted from a total loss of engine power. The pilot was conducting a local visual flight rules personal flight. The airplane, registered to and operated by the pilot and passenger, sustained substantial damage. The certificated airline transport pilot sustained minor injuries; the passenger sustained serious injuries. Visual meteorological conditions prevailed. The flight originated at Gillespie Field, San Diego, California, at 1015 hours. A Federal Aviation Administration (FAA), San Diego Flight Standards District Office, airworthiness inspector conducted the on-scene investigation. The inspector reported the airplane came to rest, right-side-up, in a rough surface, high-vegetation field about 300 yards north of Interstate 8. The right wing was canted downward. The airplane sustained extensive structural damage, including a buckled firewall, but the propeller was in the horizontal position and undamaged. San Diego Fire Department personnel told the inspector they did not detect a strong fuel odor when they arrived at the accident site. The inspector noted that the fuel tank contained " . . . only a small unmeasurable amount of fuel . . . ." The fuel tank was not compromised during the accident; however, the glass gascolator bowl was missing. The inspector found pieces of the gascolator bowl imbedded in the seal area. Recovery personnel told the inspector that there were no glass remnants of the gascolator under or within the surrounding area of the wreckage. The FAA inspector established continuity of the engine gear and valve train assembly. The inspector reported the presence of thumb compression when the crankshaft was rotated. The spark plugs exhibited normal operating signatures. Both magnetos produced spark when their respective drive shafts were rotated. Champion Aircraft Corporation Service Helps and Hints #15, Replacing of Glass Gascolator Bowl with Metal Gascolator Bowls, was originally issued on August 23, 1946, and reissued on July 1, 1964. The service letter states, in part: It has been reported that a few glass gascolator bowls have broken. Reports indicate the glass bowl broke near the bottom and was caused by a combination of vibration and too much pressure applied on the adjustment clamp. In order to eliminate any such possibility, we are changing to metal gascolator bowls as standard equipment on both our Champion Serial #4641 and up and Chief Serial #582 and up. Compliance with this service letter is not mandatory. This issue is not addressed in an airworthiness directive.