# NTSB WPR13LA009: Piper PA-38-112, N4309E, Corona, CA, October 13, 2012 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: October 13, 2012, 12:15 local (19:15 UTC) - Place: Corona, CA - Coordinates: 33.894443, -117.595832 - Nearby events: https://openairdocs.org/map.md?lat=33.8944&lon=-117.5958&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Defining event: [Approach-VFR pattern downwind: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report January 31, 2013 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration FSDO - NTSB case key (mKey): 85317 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR13LA009 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/85317/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=85317 - Page: https://openairdocs.org/ntsb/WPR13LA009 ## Probable cause Total loss of engine power during the landing approach due to insect debris in the carburetor metering valve, which resulted in fuel starvation. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine fuel and control: fuel control/carburetor](https://openairdocs.org/ntsb-findings/01057322): Aircraft › Aircraft power plant · Damaged/degraded (probable cause); cases with it: [Piper PA-38-112, 1 case](https://openairdocs.org/ntsb-findings/01057322/cases.md?model=7103812), [All aircraft, 195 cases](https://openairdocs.org/ntsb-findings/01057322/cases.md) - [Object/animal/substance: debris/dirt/foreign object](https://openairdocs.org/ntsb-findings/03022055): Environmental issues › Physical environment · Effect on equipment (probable cause); cases with it: [Piper PA-38-112, 1 case](https://openairdocs.org/ntsb-findings/03022055/cases.md?model=7103812), [All aircraft, 101 cases](https://openairdocs.org/ntsb-findings/03022055/cases.md) - [Maintenance/inspections: scheduled maint checks](https://openairdocs.org/ntsb-findings/01010520): Aircraft › Aircraft handling/service · Not serviced/maintained; cases with it: [Piper PA-38-112, 1 case](https://openairdocs.org/ntsb-findings/01010520/cases.md?model=7103812), [All aircraft, 76 cases](https://openairdocs.org/ntsb-findings/01010520/cases.md) - [Inspection: scheduled/routine inspection](https://openairdocs.org/ntsb-findings/02061520): Personnel issues › Task performance · Not specified; cases with it: [Piper PA-38-112, 1 case](https://openairdocs.org/ntsb-findings/02061520/cases.md?model=7103812), [All aircraft, 167 cases](https://openairdocs.org/ntsb-findings/02061520/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Approach-VFR pattern downwind: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [Piper PA-38-112, 10 cases](https://openairdocs.org/ntsb-events/341/sequence.md?model=7103812), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Approach-VFR pattern downwind: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Piper PA-38-112, 5 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=7103812), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Landing: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Piper PA-38-112, 17 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=7103812), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis After flying for about 1 hour, the pilot prepared the airplane for the landing approach. As he entered the downwind leg of the approach, the engine lost all power. Unable to restart the engine, the pilot performed a forced landing into an adjacent field, where the airplane sustained substantial damage. A wasp was found in the carburetor fuel bowl, and a wasp head was located wedged within the inner sleeve of the carburetor metering valve. The head was adjacent to the fuel channel hole, blockage of which would have resulted in a loss of fuel flow to the engine and subsequent loss of engine power. Both fuel tank vent ports were also found completely blocked with mud that was likely deposited by the wasp. However, the blocked fuel tank vent ports were unlikely to cause fuel starvation because fuel was present in all the supply lines and the fuel tanks were equipped with venting fuel caps, which were operational. The only path for a wasp-sized insect to access the carburetor fuel bowl was via the atmospheric bowl vent, the opening of which was located at the carburetor's air inlet. The vent leads directly to the fuel bowl and is wide enough for a wasp to pass through. The wasp most likely accessed the vent through either a hole in the air induction system, a gap in the carburetor-heat door seal, or through the carburetor-heat door opening (assuming the door had not been fully closed on the ground). It is not known when the wasp entered the fuel system. The airplane’s last annual inspection was performed about 2 1/2 years prior to the accident; however, it is unlikely the wasp would have been discovered during an annual inspection because the carburetor is not an inspection item. The insect would also be difficult to detect during preflight inspection. ## Factual narrative HISTORY OF FLIGHT On October 13, 2012, about 1215 Pacific daylight time, a Piper PA-38-112, N4309E, collided with terrain following a loss of engine power during landing at Corona Municipal Airport, Corona, California. The pilot/owner was operating the airplane under the provisions of 14 Code of Federal Regulations Part 91. The commercial pilot sustained minor injuries. The airplane was substantially damaged during the accident sequence. The local flight departed Corona about 1115. Visual meteorological conditions prevailed, and no flight plan had been filed. The pilot reported that during the landing approach he performed his pre-landing checks, and that shortly after turning on the auxiliary fuel pump, the engine lost all power. He performed troubleshooting procedures, with no increase in engine power. The airplane was on the left downwind leg of runway 07, and the pilot was concerned that he did not have enough altitude to turn towards the runway; he elected to land the airplane in a field directly ahead. During the approach, the right wing struck a tree, and the airplane descended underneath a power line, striking the airport perimeter fence and coming to rest in a field. The airplane sustained substantial damage to the right wing, firewall, and tailcone during the accident sequence. AIRCRAFT INFORMATION The low-wing, single-engine airplane, was manufactured in 1978, and equipped with a Lycoming O-235-L2C engine, serial number L-16453-15. Maintenance records indicated that the engine was overhauled and installed on the airplane in 2004. At the time of the most recent annual inspection, dated March 3, 2010, the engine had accrued a total flight time of 115 hours since overhaul. At that time, the airframe had accrued 2,021 flight hours. The engine tachometer indicated 2,075.06 hours at the accident site. The pilot reported that he kept the airplane stored at an outdoor tie-down spot at Corona Airport. TESTS AND RESEARCH Fuel Supply System Aircraft recovery personnel reported draining about 2 gallons of fuel from the left tank during the recovery operation. The right tank was breached, and a 6-foot-long by 2-foot-wide stain was present on the ground surrounding the tank. During the subsequent airframe examination by the National Transportation Safety Board (NTSB) investigator, an additional 2 gallons of fuel was observed in the left tank. The fuel lines from the tanks to the carburetor inlet were full with fuel and free of obstruction. The gascolator bowl was full of light-colored fluid consistent in color and odor with aviation gasoline, and its filter screen was free of debris. The fuel selector valve was observed in the right tank position. The valve could be moved through its detents by hand, but crumpled airframe structure had become impinged against the selector shaft, preventing smooth operation of the handle. The electrically driven fuel pump issued fuel when engaged. Examination of the wing tank vent ports, located underneath eachwing, revealed that they were completely plugged by a mud-like substance. The ports were removed, and the obstruction appeared consistent with Mud Dauber (wasp) debris. The fuel tank filler caps were of the vented type. Examination revealed that the vent flapper valve was intact, and that the vent opened appropriately with the application of low air vacuum. Carburetor The Precision Airmotive Carburetor, model MA-3A, remained undamaged, and firmly attached to the intake manifold. The fuel mixture, throttle, and carburetor heat linkages were intact and continuous to their respective cabin controls, and moved smoothly when operated. The airbox and filter assembly sustained crush damage. Although the forward surface of the filter element was coated in a wax-like substance, the filter was able to pass air when blown. The fuel inlet screen was free of debris. The carburetor was removed and opened for examination. The bowl was about half full with clear, blue-colored fuel. The float was of the brass type, and appeared intact and free of leaks. The float valve was intact, pliable, and along with the valve seat, free of contamination. A wasp-like insect was at the bottom of the bowl, adjacent to the bowl drain plug and mixture metering sleeve. Further examination of the metering valve revealed the head of a wasp-like insect wedged within the valves inner sleeve. The position of the head was adjacent to the fuel channel hole in the carburetor body. The design of the carburetor bowl allows for two direct paths to atmospheric pressure. The first is the drain plug, which, when removed, allows fuel to be drained through two, 3/32-inch-wide drain channels. The second path is that of the atmospheric bowl vent. The opening for this vent is 1/4-inch-wide, and located at the carburetor air inlet, adjacent to the throttle flange, and upstream of the fuel nozzle outlet. The vent channel continues through the carburetor body, and into the roof of the fuel bowl, where it reduces in size to a 3/16-inch orifice. Carburetor induction air enters a chin scoop intake in the lower airbox cowling, and flows directly through the filter, and into the carburetor airbox. The airbox incorporates a positive shut off (door) heat intake, so that when carburetor heat was selected, unfiltered induction air was drawn through a hose attached to a muffler shroud. Engine The engine sustained minimal damage during the accident sequence, and post impact examination did not reveal any anomalies that would have precluded normal operation. ## Aircraft - Registration: [N4309E](https://openairdocs.org/deregistered/N4309E-2018-01-19), registration cancelled 2018-01-19, S/N 38-78A0544, built 1978 (OpenAirDocs) - Reported make and model: PIPER PA-38-112 - Registry model: [Piper PA-38-112](https://openairdocs.org/model/piper-pa-38-112) (registry code 7103812) (OpenAirDocs) - Registry engine: [Lycoming 0-235 series](https://openairdocs.org/engine/lycoming-0-235-series) (registry code 41505, 4 cycle) (OpenAirDocs) - Category: Airplane - Serial number: 38-78A0544 - Airframe hours: 2075 - Engines: LYCOMING O-235 SERIES 115 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Utility; Standard, Normal - Last inspection: Annual, March 3, 2010, 54 hours before - Departed: AJO, Corona, CA - Destination: AJO, Corona, CA - Airport: AJO, Corona, runway 07, 3,200 × 60 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 49; injuries: minor; commercial; airplane ratings: single-engine sea, single-engine land; instrument ratings: airplane; medical: class 2, with waivers/limitations; last flight review February 22, 2009; seat: left; flight hours: 796 total, 770 in this make and model, 694 as pilot in command, 10 in the last 90 days, 4 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 72 °F, dew point 52 °F - Altimeter: 30.15 inHg - Observed at: AJO ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20121013024279A](https://openairdocs.org/incident/20121013024279A), Oct 13, 2012: Piper PA-38-112, Corona, CA, Destroyed. N4309E executed an emergency landing when aircraft lost power. N4309E landed south of the runway at kjao and substained heavy damage. ## Docket (13 files) The files NTSB released with the investigation on November 29, 2012, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=85317. 8.3 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 931 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40380449&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Photo 1 – Airplane (item 2, .PDF, 179 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40380686&FileExtension=.PDF&FileName=Photo%201%20%E2%80%93%20Airplane-Master.PDF - Photo 2 – Left Fuel Tank Vent Port (item 3, .PDF, 581 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40380687&FileExtension=.PDF&FileName=Photo%202%20%E2%80%93%20Left%20Fuel%20Tank%20Vent%20Port-Master.PDF - Photo 3 – Right Fuel Tank Vent Port (item 4, .PDF, 519 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40380688&FileExtension=.PDF&FileName=Photo%203%20%E2%80%93%20Right%20Fuel%20Tank%20Vent%20Port-Master.PDF - Photo 4 – Fuel Bowl Containing Wasp (item 5, .PDF, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40380689&FileExtension=.PDF&FileName=Photo%204%20%E2%80%93%20Fuel%20Bowl%20Containing%20Wasp-Master.PDF - Photo 5 - Metering Valve Inner Sleeve (item 6, .PDF, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40380690&FileExtension=.PDF&FileName=Photo%205%20-%20Metering%20Valve%20Inner%20Sleeve-Master.PDF - Photo 6 – Carburetor Drain Plug Outlet (item 7, .PDF, 612 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40380691&FileExtension=.PDF&FileName=Photo%206%20%E2%80%93%20Carburetor%20Drain%20Plug%20Outlet-Master.PDF - Photo 7 – Atmospheric Bowl Vent 1 (item 8, .PDF, 805 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40380692&FileExtension=.PDF&FileName=Photo%207%20%E2%80%93%20Atmospheric%20Bowl%20Vent%201-Master.PDF - Photo 8 – Atmospheric Bowl Vent 2 (item 9, .PDF, 733 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40380693&FileExtension=.PDF&FileName=Photo%208%20%E2%80%93%20Atmospheric%20Bowl%20Vent%202-Master.PDF - Photo 9– Atmospheric Bowl Vent 3 (item 10, .PDF, 958 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40380694&FileExtension=.PDF&FileName=Photo%209%E2%80%93%20Atmospheric%20Bowl%20Vent%203-Master.PDF - Maintenance Manual Excerpts (item 11, .PDF, 125 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40380696&FileExtension=.PDF&FileName=Maintenance%20Manual%20Excerpts-Redacted.PDF - Carburetor Overhaul Manual Excerpts (item 12, .PDF, 577 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40380697&FileExtension=.PDF&FileName=Carburetor%20Overhaul%20Manual%20Excerpts-Master.PDF - Retention / Release of Wreckage Form (item 13, .PDF, 129 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40380819&FileExtension=.PDF&FileName=Retention%20%2F%20Release%20of%20Wreckage%20Form-Redacted.PDF From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.