# NTSB SEA97LA168: Bell 47G-3B, N8494E, Idaho Falls, ID, July 14, 1997 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: July 14, 1997, 12:20 local (18:20 UTC) - Place: Idaho Falls, ID - Coordinates: 43.519142, -112.269912 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=43.5191&lon=-112.2699&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report January 28, 2000 - Report: Approved by Office Director - NTSB case key (mKey): 42657 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA97LA168 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/42657/pdf - Page: https://openairdocs.org/ntsb/SEA97LA168 ## Probable cause The pilot mismanaged his fuel supply which led to fuel exhaustion and subsequent loss of engine power. Factors contributing to the accident were the lack of adequate altitude and airspeed to successfully execute an autorotation. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(total) - nonmechanical, approach - fluid,fuel - exhaustion (cause) - fuel management - inadequate, pilot in command (cause) - Forced landing, descent - emergency - Hard landing, landing - flare/touchdown - autorotation - not possible (cause) - airspeed - inadequate (contributing factor) - altitude - inadequate (contributing factor) ## Analysis The pilot reported that upon making the last spray pass of a potato field he noted a low fuel state and turned back towards his refueling truck. At an altitude of 10-15 feet above ground and an airspeed of approximately 25 knots, the engine lost power. The pilot reported that 'when it quit I did not have the time to do any auto(rotation). It stopped and I hit the ground.' An FAA inspector confirmed the lack of fuel on board the aircraft following the accident. The height-velocity diagram for the Bell 47G-3B placed the aircraft on the boundary of the envelope for a successful autorotation at the altitude and speed at the time of the power loss. ## Factual narrative On July 14, 1997, approximately 1220 mountain daylight time, a Bell 47G-3B, N8494E, registered to Roger & Michael Hall, and being flown by a commercial pilot doing business as Eagle Aviation, Inc., incurred substantial damage during a hard landing, following a total loss of power while returning to his fueling station, approximately 11 miles east of Idaho Falls, Idaho. The pilot sustained minor injuries. No flight plan had been filed and visual meteorological conditions existed at the time. The flight, which had just completed an aerial application run, was to have been operated under 14CFR137, and originated from a location adjacent to the spray site. The pilot reported that he "was spraying a potato field. As I made the last pass I looked down and noticed my gas gauge showing low. So I turned around and head(ed) back to the load truck." He continued reporting "I was over a sod field when the engine quit. At that time I was about 250 to 300 yd (yards) from the truck and at (sic) about 10 to 15 f(ee)t above the ground and at (sic) about 25 kts. He concluded reporting "When it quit I did not have the time to do any auto(rotation). It stopped and I hit the ground." An altitude of 15 feet (above ground) at an airspeed of 25 knots places the aircraft on the boundary of the envelope for a successful autorotation (refer to CHART I). An inspector from the Federal Aviation Administration's Flight Standards District Office, Salt Lake City, Utah, traveled to the site. His examination confirmed that the fuel tanks were empty. ## Aircraft - Registration: [N8494E](https://openairdocs.org/deregistered/N8494E-2013-05-14), registration cancelled 2013-05-14, S/N 2716, built 1961 (OpenAirDocs) - Reported make and model: Bell 47G-3B - Registry model: [Bell 47G-3B](https://openairdocs.org/model/bell-47g-3b) (registry code 1181026) (OpenAirDocs) - Registry engine: [Lycoming TVO-435-GIA](https://openairdocs.org/engine/lycoming-tvo-435-gia) (registry code 41526, turbo-prop) (OpenAirDocs) - Category: Helicopter - Serial number: 2716 - Engines: Lycoming TVO-435-A1A 220 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Wood, Milton, H., doing business as Eagle Aviation - Registered owner: Hall, Roger & Michael - Airworthiness certificate: Special, Restricted (Special) - Last inspection: 100 hour, July 17, 1997, 7 hours before ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 51; commercial; airplane ratings: single-engine sea, single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: left; flight hours: 12,950 total, 1,195 in this make and model, 365 in the last 90 days, 104 in the last 30 days, 8 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 170° at 4 knots - Visibility: 60 statute miles - Lowest ceiling: none - Temperature: 81 °F, dew point 52 °F - Altimeter: 30.00 inHg - Observed at: IDA ## 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 19970714018379A](https://openairdocs.org/incident/19970714018379A), Jul 14, 1997: Bell 47G3B, Idaho Falls, ID, No damage. Crashed on aierial application. ## Other investigations on N8494E (2) 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. - [NTSB DFW05CA231](https://openairdocs.org/ntsb/DFW05CA231), Aug 16, 2005: Bell 47 (N8494E), Monette, AR, destroyed. Probable cause: The loss of control as result of a loss of hydraulic pressure for undetermined reasons. - [NTSB MIA67A0111](https://openairdocs.org/ntsb/MIA67A0111), Apr 24, 1967: Bell 47G-3B (N8494E), Athens, AL, destroyed 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.