# NTSB WPR13LA094: Piper PA-28-235, N49DS, Rock Springs, WY, January 18, 2013 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: January 18, 2013, 13:00 local (20:00 UTC) - Place: Rock Springs, WY - Coordinates: 41.589721, -109.058891 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=41.5897&lon=-109.0589&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Defining event: [Approach-VFR pattern downwind: Fuel starvation](https://openairdocs.org/ntsb-events/191) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report December 2, 2013 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Adminstration FSDO - NTSB case key (mKey): 86049 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR13LA094 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/86049/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=86049 - Page: https://openairdocs.org/ntsb/WPR13LA094 ## Probable cause The pilot's inadvertent movement of the fuel selector valve beyond its tank detent, which resulted in a total loss of engine power due to fuel starvation. Contributing to the accident was the failure of the fuel selector interlock mechanism. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Fuel system: fuel selector/shutoff valve](https://openairdocs.org/ntsb-findings/01022823): Aircraft › Aircraft systems · Incorrect use/operation (probable cause); cases with it: [Piper PA-28-235, 4 cases](https://openairdocs.org/ntsb-findings/01022823/cases.md?model=7102810), [All aircraft, 176 cases](https://openairdocs.org/ntsb-findings/01022823/cases.md) - [Action: incorrect action selection](https://openairdocs.org/ntsb-findings/02041010): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Piper PA-28-235, 2 cases](https://openairdocs.org/ntsb-findings/02041010/cases.md?model=7102810), [All aircraft, 397 cases](https://openairdocs.org/ntsb-findings/02041010/cases.md) - [Fuel system: fuel selector/shutoff valve](https://openairdocs.org/ntsb-findings/01022823): Aircraft › Aircraft systems · Failure (probable cause); cases with it: [Piper PA-28-235, 4 cases](https://openairdocs.org/ntsb-findings/01022823/cases.md?model=7102810), [All aircraft, 176 cases](https://openairdocs.org/ntsb-findings/01022823/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: Fuel starvation](https://openairdocs.org/ntsb-events/191) (defining event); cases with it: [Piper PA-28-235, 9 cases](https://openairdocs.org/ntsb-events/191/sequence.md?model=7102810), [All aircraft, 733 cases](https://openairdocs.org/ntsb-events/191/sequence.md) - [Approach-VFR pattern base: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341); cases with it: [Piper PA-28-235, 16 cases](https://openairdocs.org/ntsb-events/341/sequence.md?model=7102810), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Approach-VFR pattern base: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Piper PA-28-235, 12 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=7102810), [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-28-235, 35 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=7102810), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis After an uneventful cross-country flight, the pilot initiated the landing descent by reducing engine power. As the airplane approached the airport's base leg, he performed the landing checklist, which included switching the fuel selector valve to the left tip tank. As the airplane turned from the base to final leg, it descended too low, and he applied full engine power. The engine did not respond, and a few seconds later lost all power. With limited altitude to complete a thorough emergency check, he performed a forced landing into rough terrain. During the landing sequence, the airplane struck a fence and berm, sustaining substantial damage to both wings. Following the accident, the pilot expressed concern that he may have inadvertently starved the engine of fuel during the approach, by turning the fuel selector valve beyond its left tip tank travel limit, and to the OFF position. The airplane's fuel selector lever was fitted with an interlock mechanism, which was designed to prevent the pilot from inadvertently shutting off the fuel in this manner. Examination revealed that the mechanism had shifted, such that the fuel selector lever could be moved to a position in-between the left tip tank, and OFF detent without engaging the interlock, therefore possibly resulting in an interruption of fuel flow to the engine. Data extracted from the engine monitor, as well as the minimal quantities of fuel recovered from the fuel system components within the engine compartment, were consistent with a fuel starvation event. A postaccident examination of the engine and successful engine run revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. ## Factual narrative The FAA approved airplane flight manual and pilot's operating manual, did not prohibit the use of tip tanks during landing, stating that their total capacity is useable, and that for approach and landing the selector valve should be set to the "Proper Tank." On January 18, 2013, about 1300 mountain standard time, a Piper PA-28-235, N49DS, collided with a fence during a forced landing in Rock Springs, Wyoming. The pilot was operating the airplane under the provisions of 14 Code of Federal Regulations Part 91. The private pilot was not injured, and the airplane sustained substantial damage during the accident sequence. The cross-country flight departed Gillette-Campbell County Airport, Gillette, Wyoming, about 1110 with a planned destination of Rock Springs-Sweetwater County Airport, Rock Springs. Visual meteorological conditions prevailed, and no flight plan had been filed. The pilot reported that after initiating a descent from 12,500 feet, he approached the right base for runway 27 at Rock Springs Airport. During the approach, he switched the fuel selector valve to the left tip tank, and turned on both the carburetor heat and auxiliary fuel pump. During the turn from right base to final, the airplane descended too low, and he applied full engine power. The engine did not respond, and a few seconds later lost all power. He subsequently elected to land the airplane in rough terrain ahead. During the landing sequence, the airplane struck a fence and berm, sustaining substantial damage to both wings. The pilot expressed concern that he may have inadvertently starved the engine of fuel during the approach, by turning the fuel selector valve beyond its left tip tank travel limit, and over to the OFF position. He stated that after the engine lost power, he performed a cursory check of emergency items, but did not reach down to check the fuel selector valve, for fear that he may become disoriented, and stall the airplane. He could not specifically recall the position of the valve after the accident, but confirmed that he switched it to the OFF position while securing the airplane on the ground. A fuel receipt recovered from Fligthline Incorporated of Gillette, indicated that the he purchased 27.3 gallons of fuel for the airplane the day prior to the accident. He stated that this fuel purchase resulted in a total of 64 gallons of fuel onboard. Fuel Selector Valve The airplane was equipped with a combination fuel selector valve/fuel drain, located underneath the cabin floor, just behind the forward right seat. The valve was connected to a selection lever in the center console in the forward cabin. During the examination, the valve was moved through its entire travel range, and appropriate friction was felt within the detents at each tank position. The selection lever was equipped with an override button (interlock) between the left tip, and OFF positions, which was designed to prevent the pilot from inadvertently turning the valve to the OFF positionin-flight. During testing of the valve, it was noted that the lever could be moved midway between the OFF and left tip detents before the button prevented further movement. Engine and Airframe Examination The left tip tank was ruptured during the accident sequence, and as such an accurate assessment of its fuel quantity could not be made. The engine sustained minimal damage, exhibiting primarily crushing of the lower cowling and induction airbox. All the fuel lines forward of the firewall were intact, and contained residual droplets of fuel. About 1/2 ounce of blue-colored fuel was present within the combination fuel selector valve/fuel drain, and about 3 tablespoons of fuel was drained from the carburetor at its bowl plug. The fuel line from the left tip tank through to the selector valve was examined, and was free of obstruction. An external engine examination was performed, and no anomalies were noted that would have precluded normal operation. Engine Test Run The airplane was connected to a fuel source via the left tip tank inlet at the selector valve. The engine was subsequently started, and operated at varying speeds for a period of about 5 minutes. During that time, the engine operated smoothly throughout its speed range, with a nominal speed drop observed during a magneto check. Engine Monitor The airplane was equipped with a JP Instruments EDM 730 engine data monitoring system. The EDM 730 was configured to record engine exhaust (EGT) and cylinder head (CHT) temperatures, fuel flow, fuel used, and battery voltage at 6-second intervals. The data from the accident flight was downloaded and examined. For the majority of the flight, EGT and CHT values remained relatively constant, with a fuel flow of between 12 and 15 gph (gallons per hour). About 5 minutes before the recording ended, the data indicated a reduction in fuel flow to 9 gph, with a corresponding decrease in EGT from 1,400 to 1,250, and CHT from 325 to 285 degrees Fahrenheit (F). The reduced temperatures and fuel flow were consistent with the pilot initiating a reduction in engine power for descent. About 45 seconds before the recording ended, the fuel flow increased to 15 gph, and the EGT exhibited a spike in temperature of about 100 degrees. Shortly thereafter, the fuel pressure dropped to zero, and the CHT to fell to 500 degrees. ## Aircraft - Registration: [N49DS](https://openairdocs.org/deregistered/N49DS-2017-10-19), registration cancelled 2017-10-19, S/N 28-7610019, built 1976 (OpenAirDocs) - Reported make and model: PIPER PA-28-235 - Registry model: [Piper PA-28-235](https://openairdocs.org/model/piper-pa-28-235) (registry code 7102810) (OpenAirDocs) - Registry engine: [Lycoming 0-540 series](https://openairdocs.org/engine/lycoming-0-540-series) (registry code 41532, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 28-7610019 - Year built: 1976 - Airframe hours: 4869.4 - Engines: LYCOMING O-540 SERIES 235 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, June 19, 2013, 74.92 hours before - Departed: GCC, GILLETTE, WY - Destination: RKS, Rock Springs, WY - Airport: RKS, Rock Springs-Sweetwater County, runway 27, 10,000 × 150 ft, asphalt - Equipment: Stall warning system, Electronic multifunction display, Auto-pilot ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 55; injuries: none; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; seat: left; restraint: 3-point; flight hours: 228.3 total, 7.5 in this make and model, 171.5 as pilot in command, 12.6 in the last 90 days, 7.5 in the last 30 days, 4.5 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 250° at 20 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 34 °F, dew point 10 °F - Altimeter: 30.25 inHg - Observed at: KRKS, 1 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 20130118001059A](https://openairdocs.org/incident/20130118001059A), Jan 18, 2013: Piper PA-28-235, Rock Springs, WY, Substantial damage. On 01/18/2013 at approx 1254 LCL N49DS, a pa 28-235 sustained substantial damage while landing at Rock Springs, WY (rks) one sole on board no injuries. Day VFR… ## Docket (11 files) The files NTSB released with the investigation on October 22, 2013, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=86049. 6.4 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 390 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40401302&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Pilot Statement (item 2, .PDF, 201 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40401386&FileExtension=.PDF&FileName=Pilot%20Statement-Redacted.PDF - Photo 1 - Fuel Selector Valve (item 3, .PDF, 1.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40401309&FileExtension=.PDF&FileName=Photo%201%20-%20Fuel%20Selector%20Valve-Master.PDF - Photo 2 - Fuel Selector Valve (item 4, .PDF, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40401310&FileExtension=.PDF&FileName=Photo%202%20-%20Fuel%20Selector%20Valve-Master.PDF - Photo 3 - Fuel Selector Valve (item 5, .PDF, 1.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40401311&FileExtension=.PDF&FileName=Photo%203%20-%20Fuel%20Selector%20Valve-Master.PDF - Photo 4 - Airplane Damage (item 6, .PDF, 481 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40401312&FileExtension=.PDF&FileName=Photo%204%20-%20Airplane%20Damage-Master.PDF - Engine Monitor Graph Data (item 7, .PDF, 586 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40401304&FileExtension=.PDF&FileName=Engine%20Monitor%20Graph%20Data-Master.PDF - Engine Monitor Raw Data (item 8, .CSV, 124 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40401305&FileExtension=.csv&FileName=Engine%20Monitor%20Raw%20Data-Master.csv - Fuel Receipt (item 9, .PDF, 67 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40401306&FileExtension=.PDF&FileName=Fuel%20Receipt-Redacted.PDF - Flight Manual Excerpts (item 10, .PDF, 140 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40401307&FileExtension=.PDF&FileName=Flight%20Manual%20Excerpts-Master.PDF - Release of Aircraft Wreckage, NTSB Form 6120.15 (item 11, .PDF, 223 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40401308&FileExtension=.PDF&FileName=Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15-Redacted.PDF From the NTSB's public API. 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