# NTSB CHI08IA294: Indus T-211 Thorpedo, N107JF, La Porte, IN, September 18, 2008 - Type: NTSB incident investigation - Classification: Incident · No injuries · Incident investigation · Final report - Date: September 18, 2008, 12:45 local (16:45 UTC) - Place: La Porte, IN - Coordinates: 41.599296, -86.710807 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=41.5993&lon=-86.7108&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-cruise: Fuel exhaustion](https://openairdocs.org/ntsb-events/192) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report December 20, 2010 - Report: Approved by Office Director - Parties: Federal Aviation Administration, IndUS Aviation - NTSB case key (mKey): 68996 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI08IA294 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/68996/pdf - Page: https://openairdocs.org/ntsb/CHI08IA294 ## Probable cause A loss of engine power due to fuel exhaustion as a result of siphoning from the fuel filler neck and cap. Contributing to the incident were the fuel over-servicing which resulted in the siphoning condition, and the ASTM standards which allowed for the fuel tank filler neck/vent design. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Fluids: fuel](https://openairdocs.org/ntsb-findings/01071010): Aircraft › Fluids/misc hardware · Fluid level (probable cause); cases with it: [Indus T-211 THORPEDO, 1 case](https://openairdocs.org/ntsb-findings/01071010/cases.md?model=060002U), [All aircraft, 1,695 cases](https://openairdocs.org/ntsb-findings/01071010/cases.md) - [Fluids: fuel](https://openairdocs.org/ntsb-findings/01071010): Aircraft › Fluids/misc hardware · Incorrect service/maintenance (probable cause); cases with it: [Indus T-211 THORPEDO, 1 case](https://openairdocs.org/ntsb-findings/01071010/cases.md?model=060002U), [All aircraft, 1,695 cases](https://openairdocs.org/ntsb-findings/01071010/cases.md) - [Fuel system: fuel storage](https://openairdocs.org/ntsb-findings/01022810): Aircraft › Aircraft systems · Design (probable cause); cases with it: [Indus T-211 THORPEDO, 1 case](https://openairdocs.org/ntsb-findings/01022810/cases.md?model=060002U), [All aircraft, 60 cases](https://openairdocs.org/ntsb-findings/01022810/cases.md) - [Selection/certification/testing: equip certification/testing](https://openairdocs.org/ntsb-findings/04012015): Organizational issues › Development · FAA/Regulator; cases with it: [Indus T-211 THORPEDO, 1 case](https://openairdocs.org/ntsb-findings/04012015/cases.md?model=060002U), [All aircraft, 21 cases](https://openairdocs.org/ntsb-findings/04012015/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Prior to flight: Miscellaneous/other](https://openairdocs.org/ntsb-events/900); cases with it: [Indus T-211 THORPEDO, 1 case](https://openairdocs.org/ntsb-events/900/sequence.md?model=060002U), [All aircraft, 1,556 cases](https://openairdocs.org/ntsb-events/900/sequence.md) - [Prior to flight: Aircraft servicing event](https://openairdocs.org/ntsb-events/020); cases with it: [Indus T-211 THORPEDO, 1 case](https://openairdocs.org/ntsb-events/020/sequence.md?model=060002U), [All aircraft, 70 cases](https://openairdocs.org/ntsb-events/020/sequence.md) - [Enroute-cruise: Fuel exhaustion](https://openairdocs.org/ntsb-events/192) (defining event); cases with it: [Indus T-211 THORPEDO, 1 case](https://openairdocs.org/ntsb-events/192/sequence.md?model=060002U), [All aircraft, 804 cases](https://openairdocs.org/ntsb-events/192/sequence.md) - [Enroute-cruise: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341); cases with it: [Indus T-211 THORPEDO, 1 case](https://openairdocs.org/ntsb-events/341/sequence.md?model=060002U), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Emergency descent: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Indus T-211 THORPEDO, 1 case](https://openairdocs.org/ntsb-events/440/sequence.md?model=060002U), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) ## Analysis The light sport airplane landed at an airport for a fuel stop during a positioning flight. According to the pilot, the airplane departed on the remainder of the positioning flight and "42 [minutes] into [the] flight at [4,500 feet] the engine stopped." The pilot performed a successful forced landing to a soybean field, with no injuries or damage to the aircraft. A postincident inspection of the airplane showed that the fuel gauge indicated 16 gallons of fuel, yet there was no fuel in the fuel tank. It was later discovered that the airplane had been over-serviced with fuel contrary to a service notification warning that a siphoning condition could occur as a result of over-servicing. Following the investigation the manufacturer modified the fuel filler neck and fuel cap and subsequently issued a service bulletin informing owners of the modification. The airplane was certified to ASTM consensus standards that allowed for the airplane's fuel filler neck design. ## Factual narrative On September 18, 2008, about 1245 eastern daylight time, an Indus Aviation Inc. T-211 Thorpedo light sport airplane, N107JF, sustained minor damage during a forced landing near La Porte, Indiana, following an in-flight loss of engine power. The airplane was new and it was being delivered on a positioning flight operated under 14 CFR Part 91. Visual meteorological conditions prevailed at the time of the incident. No flight plan was on file. The commercial pilot reported no injuries. The flight originated from the Kirsch Municipal Airport (IRS), near Sturgis, Michigan, and was destined for the Chisholm-Hibbing Airport, near Hibbing, Minnesota. The pilot reported that he landed at IRS about 1130 for a fuel stop during the positioning flight. He departed IRS and 42 minutes into flight at 4,500 feet the engine stopped. The pilot said he established best glide, turned towards La Porte Municipal airport and attempted a restart. He notified approach control of the situation, secured the aircraft for and emergency landing, and landed in a soybean field approximately 3 miles from the La Porte Airport. The airplane was not damaged. Upon inspection of aircraft, the fuel indicator showed 16 gallons of fuel with no fuel in tank. The T-211 has a single bladder with 21 gallons usable fuel. According to the factory, a siphon started and emptied all the fuel out the single vent line. This slowly collapsed the bladder onto the fuel sending unit, thus the erroneous indication. In his report, the pilot recommended that the aircraft not be flown until the vent system in re-designed and proven that a siphon is no longer possible. Subsequent to the incident, the manufacturer issued service notification number IASN 2008-1. The service notification, in part, stated: ISSUE: The fuel capacity of the T11 and T211 series aircraft is 22 gallons, 21 usable. The pilot operating handbook (POH) states, and placards at the fuel filler, Do Not Fill Above Neck Bottom. This procedure is required to allow for expansion of the fuel within the fuel cell. If the aircraft is filled above the bottom of the filler neck, enough expansion of the fuel could occur that fuel could exit through the air vent on the top side of the fuel cell, and exit out the vent on the bottom of the fuselage. This situation may cause a siphoning process to be initiated. Expansion may occur when the fuel entering the cell is cooler than the fuel cell and surrounding fuselage body, or when the aircraft is left in the sun after refueling. Because the fuel cell is flexible, as opposed to a metal or fiberglass tank, the fuel envelope could contract as the fuel siphons out the vent line. This can occur on the ground or in flight. RECOMMENDED CORRECTIVE ACTION: Do not fill the fuel cell above the bottom of the filler neck. WHO MAY PERFORM CORRECTIVE ACTION: Pilot, lineman, anyone who fuels the aircraft. The pilot, as a part of the aircraft preflight, must check the fuel level to ensure the fuel level is below the bottomof the filler neck. Subsequent to service notification number IASN 2008-1, the manufacturer issued service bulletin number IASB 2009-1. The service bulletin, in part, stated: ISSUE: In the Thorpedo/Sky Skooter POH, the placards section displays the filler neck placard that states the tank must not be filled above the bottom of the filler neck. If the fuel tank is overfilled above the bottom of the filler-neck, and the fuel vent line fills with fuel, it is possible that a siphoning condition may be induced. If this condition occurs, and continues without interruption, the fuel supply may be depleted. RECOMMENDED CORRECTIVE ACTION: To provide an additional margin for error in the event the fuel tank is overfilled, the venting in the area of the fuel filler neck and fuel cap have been modified. These modifications prevent the loss of any significant amount of fuel if the vent line becomes filled with fuel. Parts and installation are approved by Indus Aviation, Inc. and are available. Contact Indus Aviation, Inc. if you are unsure if your vent system has been modified. WHO MAY PERFORM CORRECTIVE ACTION: Aircraft Owner, Light Sport Repairman, A&P or factory authorized representative. MISCELLANEOUS: It is imperative that the operating limitations described in the POH and the placard markings on the aircraft be followed. The airplane was certified to American Society for Testing and Materials (ASTM) consensus standards which allowed the T-211's fuel tank vent design. In contrast, 14 CFR Part 23 listed the following published standards for aircraft certified under it: Sec. 23.975 - Fuel tank vents and carburetor vapor vents ... (2) Each vent must be constructed to prevent siphoning of fuel during normal operation ... (7) Vents must be arranged to prevent the loss of fuel, except fuel discharged because of thermal expansion, when the airplane is parked in any direction on a ramp having a one-percent slope. ## Aircraft - Registration: [N107JF](https://openairdocs.org/aircraft/N107JF), registered now, S/N 0705D0303, built 2007 (OpenAirDocs) - Reported make and model: INDUS AVIATION INC T-211 THORPEDO - Registry model: [Indus T-211 THORPEDO](https://openairdocs.org/model/indus-t-211-thorpedo) (registry code 060002U) (OpenAirDocs) - Registry engine: [Jabiru 3300](https://openairdocs.org/engine/jabiru-3300) (registry code 34801, 4 cycle) (OpenAirDocs) - Category: Airplane - Serial number: 0705D0303 - Airframe hours: 48 - Engines: Jabiru 3300 120 horsepower reciprocating - Damage: Minor damage - Flight: Positioning, Part 91 - Operator: Executive Aircraft Sales LLC - Registered owner: Executive Aircraft Sales LLC - Airworthiness certificate: Special, Special light-sport (Special) - Last inspection: Annual, September 15, 2008 - Departed: IRS, Kirsh, MI - Destination: HIB, Hibbing, MN - Airport: PPO, La Porte Municipal Airport ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 44; injuries: none; commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, without waivers/limitations; last flight review February 1, 2008; flight hours: 5,000 total, 150 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 100° at 10 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 72 °F, dew point 54 °F - Altimeter: 30.36 inHg - Observed at: VPZ, 14 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). - [Incident 20080918856739I](https://openairdocs.org/incident/20080918856739I), Sep 18, 2008: Indusa T211THORPEDO, No damage. (-23) The pilot [privacy data omitted] left danbury, CT, on 09/17/2008, in a LSA manufactured by indus aviation, inc of dallas, TX. The T-211 thorpedo,… 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.