# NTSB IAD04LA027: Grumman G-164A, N915X, Chatsworth, NJ, July 2, 2004 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 2, 2004, 13:30 local (17:30 UTC) - Place: Chatsworth, NJ - Coordinates: 39.749168, -74.559165 - Nearby events: https://openairdocs.org/map.md?lat=39.7492&lon=-74.5592&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report October 28, 2004 - Report: Approved by Office Director - Parties: FAA FSDO - NTSB case key (mKey): 59550 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=IAD04LA027 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/59550/pdf - Page: https://openairdocs.org/ntsb/IAD04LA027 ## Probable cause A blocked internal oil passage, which resulted in inadequate lubrication of the blower impeller shaft, and the subsequent partial loss of engine power. ## Analysis Shortly after takeoff, and about 100 feet above the ground, the airplane's engine began to lose power. The pilot began to dump the load of fertilizer the airplane was carrying and then performed a forced landing into a cranberry bog. After touchdown, the airplane nosed over. An inspection of the engine revealed that the impeller shaft of the blower section of the engine was bent, and its surface was discolored from heat and exhibited signs of rotational scoring. A 1/16-inch oil passage that lubricated the impeller shaft bearings was found blocked. ## Factual narrative On July 2, 2004, at 1330 eastern daylight time, a Grumman G-164A, N915X, operated by Downstown Airport, Inc. was substantially damaged during a forced landing, shortly after taking off from a gravel airstrip in Chatsworth, New Jersey. The certificated commercial pilot was not injured. Visual meteorological conditions prevailed, and no flight plan had been filed for the local aerial application flight, conducted under 14 CFR Part 137. According to a written statement submitted by the pilot, the departure to the south was normal until about 100 feet, when the engine began to lose power. The pilot made a "slight" right turn to align the airplane with the wind and a cranberry bog. The pilot also began dumping the 800-pound load of fertilizer that was onboard the airplane. After touchdown, the airplane nosed over in the bog. The engine was disassembled and examined under the supervision of a Federal Aviation Administration (FAA) inspector at a maintenance and repair facility. The oil pump was removed and appeared to be normal, and the oil screen appeared to be clean. The blower (supercharger) section of the engine was also examined. Several impeller blades were damaged or missing, and the remaining portions of the impeller exhibited signs of melting and breakage. The impeller shaft was bent, and its surface was discolored from heat and exhibited signs of rotational scoring. The impeller shaft bushings were worn and "oversize", and the blower shaft attach nut also exhibited heat discoloration. Further examination of the engine revealed metal contamination in the engine cylinders. According to the chief inspector at the facility where the engine was disassembled, the impeller shaft was supported by two bronze bushings that were lubricated by engine oil via a 1/8-inch hole in both of the bushings, and a 1/16-inch hole in one of the bushings. The 1/16-inch hole was found blocked. The inspector additionally stated that failure of the bronze bushing would cause the impeller shaft to "wobble," and permit contact between the blower and the rear case, which would then result in excessive damage to the impeller, impeller shaft, blower, and rear case. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(partial) - mech failure/malf, takeoff - lubricating system,oil port/passage,internal - blocked(partial) (cause) - eng assembly,blower/impeller/integral supercharger - failure - Forced landing, emergency descent/landing - Nose over, emergency landing after takeoff - terrain condition - muskeg ## Aircraft - Registration: [N915X](https://openairdocs.org/aircraft/N915X), registered now, S/N 434, built 1967 (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 R-985 series](https://openairdocs.org/engine/pratt-whitney-r-985-series) (registry code 52008, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 434 - Airframe hours: 5553.22 - Engines: Pratt & Whitney R-1340 AN-1 600 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Registered owner: Downstown Airport Inc - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, March 8, 2004, 54.17 hours before - Departed: NONE, Chatsworth, NJ - Airport: NONE, Haines Airstrip, runway 14, 1,850 × 200 ft, gravel ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 73; injuries: none; commercial; airplane ratings: single-engine land; medical: class 2, valid medical--w/ waivers/lim; last flight review March 4, 2003; seat: center; flight hours: 11,035 total, 8,500 in this make and model, 103 in the last 90 days, 52 in the last 30 days, 4 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 140° at 11 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 82 °F, dew point 70 °F - Altimeter: 30.02 inHg - Observed at: ACY, 18 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 20040702024039A](https://openairdocs.org/incident/20040702024039A), Jul 2, 2004: Scwzer G164A, Chatsworth, NJ, Substantial damage. (-23) Pilot stated he took off with 800 ILS. Of fertilizer. Start of take-off was normal. About 75' to 100', engine started losing power and began smoking.… ## Other investigations on N915X (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 NYC78FHM22](https://openairdocs.org/ntsb/NYC78FHM22), Jul 24, 1978: Grumman G-164A (N915X), Warwick, NY, 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.