# NTSB WPR13LA212: Boeing A75N1, N985SS, Santa Rosa, CA, April 20, 2013 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: April 20, 2013, 10:27 local (17:27 UTC) - Place: Santa Rosa, CA - Coordinates: 38.508888, -122.812774 - Nearby events: https://openairdocs.org/map.md?lat=38.5089&lon=-122.8128&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering: Fuel related](https://openairdocs.org/ntsb-events/190) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report August 13, 2013 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 86774 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR13LA212 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/86774/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=86774 - Page: https://openairdocs.org/ntsb/WPR13LA212 ## Probable cause The partial loss of engine power due to fuel contamination and partially blocked fuel screens. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Fuel system](https://openairdocs.org/ntsb-findings/01022800): Aircraft › Aircraft systems · Damaged/degraded (probable cause); cases with it: [All aircraft, 181 cases](https://openairdocs.org/ntsb-findings/01022800/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering: Fuel related](https://openairdocs.org/ntsb-events/190) (defining event); cases with it: [All aircraft, 361 cases](https://openairdocs.org/ntsb-events/190/sequence.md) - [Landing: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [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: [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis While joining up in formation flight with a second airplane, the pilot reduced engine power to slow his airplane. When he subsequently tried to increase the engine power, he noticed no response from the engine. The pilot stated that the engine was still running; however, the adjustment of the throttle control and the electric fuel boost pump did not alter the engine's power setting. The pilot performed a forced landing to a vineyard, and the airplane nosed over during the landing roll. Postaccident examination of the engine revealed that the main fuel system screen contained a fuzzy, spongy material along with other debris. The throttle body screen also contained small debris particles. Debris was also found in fuel that was removed from the lower fuel tank. It is likely that the debris within the fuel system restricted fuel flow to the engine and limited the power output. The source of the debris was undetermined. ## Factual narrative On April 20, 2013, about 1027 Pacific daylight time, a Boeing A75N1 airplane, N985SS, was substantially damaged during a forced landing near Santa Rosa, California. The airplane was registered to and operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91. The commercial pilot, sole occupant of the airplane, was not injured. Visual meteorological conditions prevailed and no flight plan was filed for the local personal flight which originated from Petaluma, California, about 1000. The pilot reported that while joining up in formation flight with a second airplane, he reduced power to slow his airplane down. As he increased the throttle, he noticed no response from the engine. The pilot stated that the engine was still running, however, movement in the throttle and application of the electric fuel boost pump would not alter the engine's power setting. The pilot initiated a forced landing to a vineyard. During the landing roll, the airplane nosed over. Examination of the airplane by a Federal Aviation Administration (FAA) inspector revealed that the upper left wing was structurally damaged. Examination of the recovered engine revealed that the throttle linkage remained attached and moved from stop to stop by hand. The main fuel system screen contained a fuzzy, spongy material along with other debris. The throttle body fuel screen contained many small particles. Fuel was removed from both the main and lower fuel tanks. Debris was also located within the lower fuel tank fuel sample. The source of the debris was undetermined. ## Aircraft - Registration: N985SS (not matched to a registry record) - Reported make and model: BOEING A75N1 - Category: Airplane - Serial number: 75-3431 - Airframe hours: 9582 - Engines: Pratt & Whitney R985 450 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Bell Patrick C - Registered owner: Bell Patrick C - Airworthiness certificate: Standard, Normal - Last inspection: Annual, February 1, 2013, 25 hours before - Departed: Petaluma, CA - Destination: Petaluma, CA ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 67; injuries: none; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; seat: front; flight hours: 2,700 total, 500 in this make and model, 2,700 as pilot in command, 50 in the last 90 days, 15 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 200° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 70 °F, dew point 41 °F - Altimeter: 30.07 inHg - Observed at: STS, 5 nm away ## 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 20130420005339A](https://openairdocs.org/incident/20130420005339A), Apr 20, 2013: Boeing A75N1(PT17), Santa Rosa, CA, Substantial damage. In level flight and slowing to match speed of nearby fellow stearman, the throttle became unresponsive and engine remained at idle through all throttle… ## Docket (2 files) The files NTSB released with the investigation on June 14, 2013, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=86774. 1.3 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 567 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40393416&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Reports from Federal Agencies - FAA Examination Summary (item 2, .PDF, 771 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40393417&FileExtension=.PDF&FileName=Reports%20from%20Federal%20Agencies%20-%20FAA%20Examination%20Summary-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.