# NTSB NYC05LA126: Grumman G-164A, N5495, Felton, DE, August 1, 2005 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: August 1, 2005, 09:40 local (13:40 UTC) - Place: Felton, DE - Coordinates: 39.012779, -75.533607 - Nearby events: https://openairdocs.org/map.md?lat=39.0128&lon=-75.5336&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report April 25, 2006 - Report: Approved by Office Director - Parties: Honeywell Engines, Systems & Services, FAA FSDO-17 - ADs cited in the narratives: [AD 86-08-06 R1](https://openairdocs.org/ad/86-08-06-R1) (OpenAirDocs) - NTSB case key (mKey): 62094 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC05LA126 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/62094/pdf - Page: https://openairdocs.org/ntsb/NYC05LA126 ## Probable cause The mechanic's inadequate annual inspection, and failure to comply with an airworthiness directive, which resulted in a total failure of the second stage turbine rotor. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(total) - mech failure/malf, maneuvering - aerial application - turbine assembly,turbine wheel - failure,total - maintenance,annual inspection - inadequate, other maintenance personnel (cause) - maintenance,compliance with ad - not performed, other maintenance personnel (cause) - Forced landing, descent - emergency - In flight collision with terrain/water, emergency landing - terrain condition - ground ## Analysis While returning to a private airstrip, the pilot heard a loud explosion from the engine. The engine lost all power, and the pilot performed a forced landing to a soybean field. During the landing, the right wing contacted the ground and the airplane came to rest inverted. The airplane was equipped with a Honeywell (Garrett) TPE331-43A turboprop engine. Examination of the engine revealed that the second stage turbine rotor was fractured, separated, and lodged in the back of the engine. The second stage turbine stator seal plate assembly exhibited warpage. The evidence was consistent with the warped second stage turbine stator seal plate contacting the second stage turbine rotor, causing the rotor to separate. Airworthiness directive (AD) 86-08-06 R1 pertained to the accident engine, and required an x-ray inspection of the second stage turbine stator seal plate assembly. The purpose of the AD was to detect and repair engines with second stage turbine stator seal plate assemblies that exhibited warpage. The last annual inspection of the airplane was performed about 4 months prior to the accident. According to the aircraft logbooks, the airframe and powerplant mechanic with an inspection authorization (IA) noted the AD as not applicable due to engine model number. However, the subject engine model number did require completion of the AD. ## Factual narrative On August 1, 2005, about 0940 eastern daylight time, a Grumman G-164A, N5495, was substantially damaged during a forced landing, following a total loss of engine power while maneuvering near Felton, Delaware. The certificated commercial pilot was not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the local aerial application flight conducted under 14 CFR Part 137. The pilot stated that he was returning to a private airstrip after a 25-minute aerial application flight. The airplane was about 500 feet agl, when the pilot heard a loud explosion from the engine. The pilot immediately began looking for a suitable field to perform an emergency landing. He then observed a soybean field, and initiated a right turn in an attempt to glide to the field. The airplane was descending rapidly, and before the pilot could level the wings, the right wing contacted the ground. The airplane subsequently bounced hard on the main gear and came to rest inverted. The airplane was equipped with a Honeywell (Garrett) TPE331-43A turboprop engine. Initial examination of the engine by a Federal Aviation Administration (FAA) inspector revealed that the second stage turbine rotor had separated. The engine was subsequently disassembled and inspected at the manufacturer's facility, under the supervision of an FAA inspector. The inspector noted that the second stage turbine rotor was fractured, separated, and lodged in the back of the engine. The second stage turbine stator seal plate assembly exhibited warpage. In addition, the forward face of the second stage turbine rotor exhibited a cut groove, consistent with contact between the second stage turbine stator seal plate and the second stage turbine rotor. The FAA inspector stated that airworthiness directive (AD) 86-08-06 R1 pertained to the accident engine, and required an x-ray inspection of the second stage turbine stator seal plate assembly. The purpose of the AD was to detect and repair engines with second stage turbine stator seal plate assemblies that exhibited warpage. The last annual inspection of the airplane was performed in April 2005, by an airframe and powerplant mechanic with an inspection authorization (IA). According to the aircraft logbooks, the IA noted the AD as "N/A by model #." However, the subject engine model number did require completion of the AD. ## Aircraft - Registration: [N5495](https://openairdocs.org/deregistered/N5495-2013-04-18), registration cancelled 2013-04-18, S/N 1029, built 1973 (OpenAirDocs) - Reported make and model: Grumman G-164A - Registry model: [Grumman G-164A](https://openairdocs.org/model/grumman-g-164a) (registry code 3952704) (OpenAirDocs) - Registry engine: [Pratt & Whitney R1340 series](https://openairdocs.org/engine/pratt-whitney-r1340-series) (registry code 52016, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 1029 - Airframe hours: 5523 - Engines: Garrett TPE331-43A 575 horsepower turbo prop - Damage: Substantial damage - Flight: Aerial application, Part 137 - Registered owner: First State Aerial Applicators Inc - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, April 1, 2005, 198 hours before - Departed: NONE, Felton, DC - Destination: NONE - Airport: NONE, Hrupsa Airstrip ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 23; injuries: none; commercial; airplane ratings: single-engine land; medical: class 2, without waivers/limitations; last flight review January 1, 2005; seat: single; flight hours: 2,295 total, 415 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 350° at 6 knots - Visibility: 7 statute miles - Lowest ceiling: 2,000 ft broken - Temperature: 77 °F, dew point 70 °F - Altimeter: 30.18 inHg - Observed at: DOV, 10 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 20050801024429A](https://openairdocs.org/incident/20050801024429A), Aug 1, 2005: Scwzer G164A, Felton, DE, Substantial damage. (-23) On August 1, 2005 about 0940 eastern daylight time, N5495 a Grumman G-164A, being operated by 1st state aerial applications was substantially damaged… ## Other investigations on N5495 (1) 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 MKC87LA050](https://openairdocs.org/ntsb/MKC87LA050), Feb 14, 1987: Grumman G-164A-600 (N5495), Hazen, AR, 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.