# NTSB ANC18LA034: Grumman TBM-3, N337VT, Fort Apache, AZ, May 6, 2018 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Class 3 · Limited · Final report - Date: May 6, 2018, 13:38 local (20:38 UTC) - Place: Fort Apache, AZ - Coordinates: 33.770057, -109.980171 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=33.7701&lon=-109.9802&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-cruise: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: Serious injuries - Injuries: 2 serious - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Alaska Regional Office - Parties: Federal Aviation Administration FSDO - NTSB case key (mKey): 97198 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC18LA034 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/97198/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=97198 - Page: https://openairdocs.org/ntsb/ANC18LA034 ## Probable cause A partial loss of engine power for reasons that could not be determined based on the available information. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Not determined](https://openairdocs.org/ntsb-findings/05000000): Not determined › Not determined · Unknown/Not determined (probable cause) ## Analysis The pilot and passenger were conducting a cross-country flight in the pilot's newly-purchased and refurbished World War II-era airplane when the engine experienced vibrations, smoke, an oil leak, and a partial loss of power. The airplane was over remote, rugged, tree-covered terrain with no emergency landing areas, and the occupants, who were wearing emergency parachutes, egressed about 1,500 ft above ground level. Both the pilot and passenger sustained serious injuries during their landings under parachute. Radar data indicated that the airplane continued a steady descent into terrain. The wreckage was never located despite numerous searches; therefore, the engine could not be examined and the reason for the loss of engine power or smoke and vibrations could not be determined. ## Factual narrative On May 6, 2018, about 1338 mountain standard time, a Grumman TBM-3E airplane, N337VT, was presumed destroyed when it was involved in an accident near Fort Apache Reservation, Arizona. The private pilot and pilot-rated passenger sustained serious injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot was relocating the newly-purchased airplane from California to Illinois. The airplane had undergone refurbishment and condition inspections during the previous 6 months. Before the flight, the airplane was loaded with emergency and survival gear and the pilot and passenger watched the parachute manufacturer's safety video. On the morning of the accident, the pilot flew from Zamperini Field Airport (TOA), Torrance, California, to Ak-Chin Regional Airport (A39), Maricopa, Arizona. After refueling, the pilot departed A39 and climbed to an altitude between 11,500 ft and 12,000 ft mean sea level (msl). About 45 minutes into the flight, the pilot heard a loud bang with vibrations and thick smoke entered the cockpit. He stated that the engine was operating, but not producing enough power to maintain altitude. The passenger stated that he saw sheets of oil exiting the right side of the engine cowling. As the airplane descended, they determined that there were no safe landing areas due to trees and rugged terrain, and decided to egress about 1,500 ft above ground level (agl). The passenger exited first, followed by the pilot. Both parachutes deployed successfully; however, the pilot and passenger received serious injuries after landing in trees and falling to the ground, and were unable to call for rescue due to the lack of cell phone coverage in the area. The following morning, about 1100, a fire service truck passing through the area found the pilot and passenger and they were subsequently transported to a nearby medical facility via ambulance. A review of Federal Aviation Administration air traffic control radar data revealed that the airplane continued eastbound on a stable, descending flight path after the pilot and passenger egressed. The last radar return at 1337:44 was at 10,000 ft msl, (about 1,900 ft agl) 19 miles east of Whiteriver Airport (E24), Whiteriver, Arizona, and 8 miles southwest of Mount Baldy. Multiple air and ground searches were conducted; however, the airplane was not located. ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-cruise: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event) - [Enroute-cruise: Fire/smoke (non-impact)](https://openairdocs.org/ntsb-events/150) - [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470) ## Aircraft - Registration: [N337VT](https://openairdocs.org/deregistered/N337VT-2021-01-09), registration cancelled 2021-01-09, S/N 53337, built 1945 (OpenAirDocs) - Reported make and model: GRUMMAN TBM-3 (E) - Registry model: [Grumman TBM-3](https://openairdocs.org/model/grumman-tbm-3) (registry code 3950308) (OpenAirDocs) - Registry engine: [Wright R-2600-20](https://openairdocs.org/engine/wright-r-2600-20) (registry code 67123, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 53337 - Year built: 1945 - Airframe hours: 5060.3 - Engines: Wright R 2600-20 reciprocating - Damage: Destroyed - Fire: Unknown - Flight: Personal, Part 91 - Airworthiness certificate: Special, Limited (Special) - Last inspection: Condition, February 28, 2018, 6 hours before - Departed: A39, MARICOPA, AZ - Destination: ABQ, ALBUQUERQUE, NM ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 58; injuries: serious; private; airplane ratings: single-engine sea, single-engine land; medical: unknown, with waivers/limitations; last flight review January 1, 2017; seat: front; restraint: 4-point; flight hours: 1,900 total, 25 in this make and model, 1,850 as pilot in command, 15 in the last 90 days, 10 in the last 30 days, 0 in the last 24 hours - Pilot-rated passenger; age 54; injuries: serious; private; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; seat: center; restraint: 4-point ## Weather - Conditions: Visual (VMC), Day - Wind: 140° at 6 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 81 °F, dew point 21 °F - Altimeter: 30.14 inHg - Observed at: KCNY, 6 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 20180506000359A](https://openairdocs.org/incident/20180506000359A), May 6, 2018: Grumman TBM-3, Fort Apache, AZ, Destroyed. On may 6th, 2018, the aircraft departed ak-chin reginal airport (A39) enroute for sante fe, NM. Approximately 1 hour into the flight the engine experienced a… ## Docket (5 files) The files NTSB released with the investigation on March 26, 2021, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=97198. 30.4 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 9 pages, 570 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12095193&FileExtension=pdf&FileName=6120%20master%20ANC18LA034%20V2_Redacted-Rel.pdf - Pilot statement (item 2, PDF, 16 pages, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11967104&FileExtension=pdf&FileName=Pilot%20statement%20TBM%20Crash_Redacted-Rel.pdf - Passenger record of conversation (item 3, PDF, 2 pages, 131 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11966710&FileExtension=pdf&FileName=ROC%20Pax%20Franzese%20-Rel.pdf - FAA radar plot (item 4, PDF, 2 pages, 229 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12053484&FileExtension=pdf&FileName=TBM%20Photo%20Template%202-Rel.pdf - Maintenance logbook entries (item 5, PDF, 13 pages, 28.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11966978&FileExtension=pdf&FileName=N337VT%20log%20entries%20prop%20engine%20airframe_Redacted-Rel.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.