Accident Summary
On August 5, 2014, about 1115 Pacific daylight time, a Christian Industries Inc. Pitts-S2B, N88EW, was substantially damaged during a forced landing near the Oceanside Municipal Airport (OKB) in Oceanside, California. The airplane was operated by the pilot under 14 Code of Federal Regulations Part 91. The airline transport rated pilot and his passenger were not injured. Visual meteorological conditions prevailed and no flight plan was filed for the personal flight, which originated from Mc Clellan-Palomar Airport (CRQ) in Carlsbad, California, about 1047.
Pilot's Account
The pilot reported to the NTSB investigator-in-charge that prior to takeoff, he noted three-quarters of a tank of fuel, which he felt was sufficient for a 30-minute flight plus VFR reserve. He departed to conduct spin practice and observed the fuel gauge still indicating three-quarters of a tank. After performing several spins for about 15 minutes, he leveled off and noticed the fuel sight gauge was full of fuel with no air bubble, which he considered not unusual after aerobatics. While flying back to CRQ, the engine began to run rough. The pilot verified oil pressure and the fuel sight gauge, which indicated below half a tank, with the fuel level varying with throttle position. He decided to divert to OKB, and shortly after, the engine lost power.
Approaching OKB, the pilot performed a left circling approach to runway 24 but realized he was too high on base leg. He then executed a left side slip to increase descent, but felt unsafe to land. He attempted a right 270-degree turn but realized he could not make the runway and initiated a forced landing to an open field. The airplane landed hard and nosed over about 200 yards from the approach end of runway 24.
In a later telephone conversation, the pilot reiterated that the fuel sight gauge bubble disappeared after a few aerobatic maneuvers. He noted that while the engine was running erratic, oil pressure appeared lower than normal. When asked about the fuel, the pilot suggested there must have been a leak in the system that caused fuel exhaustion.
Post-Accident Examination
Examination by an FAA inspector revealed structural damage to both wings and fuselage. Before moving the airplane, the inspector removed the main fuel tank cap and observed approximately one to two cups of liquid expel from the tank. The wreckage was recovered for further examination.
At the recovery facility, the upper and lower wings had been removed for transport. Recovery personnel reported no fuel in the upper wing header tank prior to removal. About 1 or 2 ounces of bright blue, debris-free fuel was removed from the fuel line between the fuel metering unit and the engine-driven fuel pump. About 2 to 3 ounces of yellow liquid were removed from the fuel selector valve strainer, and about 1 ounce from the fuel transfer valve drain. All liquids tested negative for water. All fuel lines were attached and secure, and no evidence of fuel leaks was found.
Prior to an engine run, the airplane was placed in a near level attitude. Five gallons of fuel were added to the main tank, and the gauge indicated about 1/4 tank. An additional 5 gallons brought the gauge to about 1/2 tank. The engine was primed using the boost pump and started. Due to propeller damage, it was run at idle for 5 minutes uneventfully before being shut down with the mixture lever. No mechanical anomalies were noted that would have precluded normal operation.