# NTSB ATL07LA131: Grumman G-164A, N8761H, Pittsgrove, NJ, September 29, 2007 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: September 29, 2007, 17:20 local (21:20 UTC) - Place: Pittsgrove, NJ - Coordinates: 39.613334, -75.189163 - Nearby events: https://openairdocs.org/map.md?lat=39.6133&lon=-75.1892&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report November 29, 2007 - Report: Approved by Office Director - Parties: PHL FSDO - NTSB case key (mKey): 66787 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ATL07LA131 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/66787/pdf - Page: https://openairdocs.org/ntsb/ATL07LA131 ## Probable cause A partial loss of engine power due to low compression for undetermined reasons. ## 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, maneuvering - reason for occurrence undetermined - engine assembly,cylinder - low compression (cause) - Forced landing, descent - emergency - In flight collision with terrain/water, emergency descent/landing - terrain condition - ground - Nose over, emergency descent/landing ## Analysis The pilot was maneuvering the airplane at 50 feet after completing a spray run and heard a "pop" sound. The airplane started to descend, the pilot applied power and the rpm came up to 2300 to 2400 rpm. The airplane collided with the ground and nosed over inverted during the forced landing. The engine was removed and a partial disassembly was completed. A compression test was conducted and 3 cylinders had low compression. No other anomalies were noted with the engine. The cause of the loss of cylinder compression was not determined. ## Factual narrative On September 29, 2007, at 1720 eastern daylight time, a Grumman G-164A, N8761H, registered to Salem Spray Service, Inc., operating as a 14 CFR Part 137 aerial application flight, experienced a partial loss of engine power while maneuvering in the vicinity of Pittsgrove, New Jersey. The pilot made a forced landing to a corn field, the airplane nosed over inverted, and received substantial damage to the airframe. Visual meteorological conditions prevailed and no flight plan was filed. The commercial pilot reported no injuries. The flight originated from Salem, New Jersey, on September 29, 2007, at 1655. The pilot stated he initiated a spray run from east to west at 10 feet parallel to the rows. The pilot completed a trim pass on the end of the rows, pulled up to 50-feet and heard a "pop" sound. The airplane started to descend and the pilot applied power. The rpm came up to 2300 to 2400 rpm and the airplane continued its descent. The pilot was attempting to level the airplane when it collided with the ground and nosed over inverted. The engine was removed and examined by the FAA. The fuel and oil elements, and housing were removed, and no contaminants were noted. An access plug on the engine was removed and the two cam rings were observed through several engine rotations. A compression test was conducted, and cylinders 1, 5, and 8 had low compression. The rocker covers were removed and valve action was observed through several engine rotations. The valves were "staked", and a compression check was completed resulting in low compression. A valve lash check was completed and no anomalies were noted. The cylinders were removed, inverted, and filled partially with gasoline to determine if any valve leakage was present with negative results. Visual examination of the valves revealed no burnt valves. The pistons displayed no indication of burning and no anomalies were noted with the ring gaps. The valves were removed from the cylinder head assemblies and neither the valves or the valve seats were burnt or scored. No foreign objects were noted in the cylinders, intake and exhaust ports, and exhaust manifolds. The supercharger impeller was examined for evidence of wobble or play and no anomalies were noted. The magneto covers were removed, inspected for rotation and sparking, and no anomalies were noted. The FAA concluded, "After performance of the above listed items, it was determined that three each cylinders have lost compression for undetermined reasons." ## Aircraft - Registration: [N8761H](https://openairdocs.org/aircraft/N8761H), registered now, S/N 1516, built 1976 (OpenAirDocs) - Reported make and model: Grumman G-164A - Registry model: [Grumman American Avn. G-164A](https://openairdocs.org/model/grumman-american-avn-g-164a) (registry code 3960202) (OpenAirDocs) - Registry engine: [Lycoming TI0-540 series](https://openairdocs.org/engine/lycoming-ti0-540-series) (registry code 41533, turbo-prop) (OpenAirDocs) - Category: Airplane - Serial number: 1516 - Airframe hours: 4383 - Engines: Pratt & Whitney R-985 14B reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Registered owner: Salem Spray Service Inc. - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, August 1, 2007, 22 hours before - Departed: NJ74, Salem, NJ ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 46; injuries: none; commercial, flight instructor; airplane ratings: single-engine land, single-engine sea; instrument ratings: airplane; medical: class 2, with waivers/limitations; last flight review July 1, 2007; seat: front; flight hours: 3,413 total, 1,001 in this make and model, 3,242 as pilot in command, 119 in the last 90 days, 26 in the last 30 days, 3 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 75 °F, dew point 43 °F - Altimeter: 30.30 inHg - Observed at: KMIV, 8 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 20070929830599A](https://openairdocs.org/incident/20070929830599A), Sep 29, 2007: Scwzer G164A, Pittsgrove, NJ, Substantial damage. (-23) On Saturday, September 29, 2007 at 4:55 pm eastern daylight time, a Grumman G-164A, N8761H, ser# 1516, was substantially damaged after an emergency… ## Other investigations on N8761H (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 GAA15CA250](https://openairdocs.org/ntsb/GAA15CA250), Aug 28, 2015: Grumman American Avn. G 164A (N8761H), Welsh, LA, substantial damage. Probable cause: The pilot's failure to maintain directional control during landing, which resulted in a runway excursion and a ground loop. 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.