WPR15LA141
2015-04-04 · Santa Maria, California, United States · Minor · 1 aircraft · Status: Completed
Airport SMX
Aircraft involved
Probable cause & findings
The engine failure due to oil starvation, which resulted from the installation of an unapproved oil quick drain valve that subsequently led to the inadvertent draining of the oil when the nose landing gear was retracted. Contributing to the accident was the lack of required warning placards on the engine mounts.
Factual narrative
On April 4, 2015, about 1131 Pacific daylight time, a Piper PA-28R-200, N5469T, sustained substantial damage during a forced landing following a reported loss of engine power, near the Santa Maria Public Airport (SMX) Santa Maria, California. The airplane was registered and operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91. The two Airline Transport Pilots sustained minor injuries and the passenger was not injured. Visual meteorological conditions prevailed and no flight plan was filed for the personal flight. The local flight originated from SMX about 1120. The pilot reported that during climb out, about 3,500 feet mean sea level (msl), the engine lost partial power, and he turned the airplane back towards the airport. Shortly thereafter, the pilot stated that the engine lost all power and he elected to initiate a forced landing to a nearby clearing. The airplane came to rest upright, in a strawberry field about 4 miles southeast from SMX. Examination of the airplane by a Federal Aviation Administration inspector revealed that the wings sustained substantial damage during the forced landing. The airplane was recovered to a secure storage facility for further examination. Further examination of the recovered wreckage by the National Transportation Safety Board investigator-in-charge revealed that both wings and the horizontal stabilizers were previously removed to facilitate transport of the wreckage. The engine remained attached to the airframe. Examination of the Lycoming Motors IO-360-C1C engine revealed that all accessories and cylinders remained attached to their respective mounts. Two cracks were observed on the upper portion of the engine crankcase near the number two cylinder mounting surface. The crankshaft would not rotate by hand. An oil quick drain oil valve was installed on the engine. According to the Piper Service Letter number 910, Subject Engine Quick Drain Valve, dated December 29, 1980, was issued to make maintenance personnel aware of the correct oil quick drain valve installment on the PA-28-200 model airplane. The letter then provides a sketch of the incorrect oil quick drain valve and the correct oil quick drain valve. According to the service letter, the oil quick drain valve installed on the airplane was consistent with the sketch of the incorrect valve. Further, Airworthiness Directive (AD) 81—11-02 R1, stated "to prevent possible loss of oil due to installation of an incorrect engine oil quick drain valve, to accomplish the following: Install two warning placards, one on each side of the engine mounts…"caution, unapproved oil drain valves can cause inadvertent draining when the gear is retracted-use only manufacturer approved part". The AD goes on to state the approved part number. The installed oil quick drain valve part number on the accident airplane did not match the approved part number. The AD states "if an incorrect valve is installed, replace it with the approved part number". Further, no warning placards were observed on the accident airplane's engine mounts. When the nose gear assembly was actuated into its up and locked position, the bolt connecting the nose gear assembly would strike the oil quick drain valve. Several impact marks were present on the oil quick drain valve and the nose gear assembly bolt, consistent with them striking each other. Oil residue was observed on the left lower portion of the engine cowling and on the belly of the airplane. A minimal amount of oil was observed in the oil filter and oil sump. No oil residue was observed on, or near the cracks in the crankcase. In summary, the examination of the engine revealed that an incorrect oil quick drain valve was installed. Postaccident examination of the recovered airframe and engine revealed no additional anomalies that would preclude normal operation. An FAA Inspector's review of the airplane's maintenance records revealed that oil quick drain valve was installed on April 2, 2015. The pilot reported that, during climbout, while the airplane was about 3,500 ft mean sea level, the engine lost partial power. He then turned the airplane back toward the airport. Shortly thereafter, the engine lost all power, and the pilot chose to initiate a forced landing to a nearby field about 4 miles southeast of the airport. During postaccident examination of the engine, two cracks were observed on the upper portion of the engine crankcase near the No. 2 cylinder mounting surface. The crankshaft would not rotate by hand. Oil residue was observed on the left lower portion of the engine cowling and on the airplane's belly. A minimal amount of oil was observed in the oil filter and oil sump. Review of the airplane's maintenance records revealed that an oil quick drain valve was installed on the engine 2 days before the accident. An aircraft manufacturer service letter (SL) and an airworthiness directive (AD) had been issued about 14 years before the accident to inform maintenance personnel about which oil quick drain valve should be installed on the accident make and model airplane. The SL provided a sketch of both the incorrect and correct oil quick drain valves, and the AD provided the approved part number. Examination of the engine revealed that the incorrect oil quick drain valve was installed on the engine. When the nose landing gear (NLG) assembly was actuated into its up-and-locked position, the bolt connecting the NLG assembly struck the oil quick drain valve, and several impact marks were present. It is likely that this damage resulted in the loss of oil and subsequent oil starvation to the engine. The AD also required that two warning placards be installed, one on each side of the engine mounts, stating that unapproved oil quick drain valves can cause inadvertent draining when the gear is retracted and to use only the manufacturer-approved part to prevent the loss of oil due to the installation of an incorrect oil quick drain valve. No placards were observed on the engine mounts. Source: NTSB Aviation Accident Database Retrieved: 2026-02-12
NTSB Findings
FAA avdata. C = Cause, F = Factor.
- C Personnel issues-Task performance-Maintenance-Unauthorized maint/repair-Maintenance personnel - C
- C Aircraft-Fluids/misc hardware-Fluids-Oil-Fluid level - C
- F Aircraft-Aircraft handling/service-Placards and markings-(general)-Not installed/available - F
Verbatim from NTSB's published report. Source file
NTSB_2015_WPR15LA141.txt.
Findings + structured fields enriched from FAA avall.mdb.
Full investigation docket on
data.ntsb.gov ↗.
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