# NTSB investigations: Pratt & Whitney R-985 series: Loss of engine power(partial) - mech failure/malf NTSB aviation accident and incident investigations since 1962: the probable cause, findings, aircraft, crew, weather and docket of each, linked to the FAA registry and the FAA’s own reports. ## Latest cases - [NTSB CHI05CA256](https://openairdocs.org/ntsb/CHI05CA256.md): Boeing A75N1 · Ellisville, IL · Accident · No injuries · Data collection · Final report · Sep 7, 2005 · N52551 · Substantial damage > The loss of engine power due to the failure of the number four connecting rod. A factor to the accident was the soybean crop. - [NTSB LAX05LA152](https://openairdocs.org/ntsb/LAX05LA152.md): Grumman G-164A · Yuba City, CA · Accident · No injuries · Limited investigation · Final report · Apr 30, 2005 · N5304 · Substantial damage > a partial loss of engine power due to multiple cracks in the number 7 cylinder. The reasons for the cracks were not determined - [NTSB SEA04LA139](https://openairdocs.org/ntsb/SEA04LA139.md): Grumman G-164A · Nyssa, OR · Accident · Minor injuries · Limited investigation · Final report · Jul 23, 2004 · N7220 · Substantial damage > The failure (fracture) of the number four cylinder head during an aerial application run. Factors include the soft crop-covered terrain. - [NTSB IAD04LA027](https://openairdocs.org/ntsb/IAD04LA027.md): Grumman G-164A · Chatsworth, NJ · Accident · No injuries · Limited investigation · Final report · Jul 2, 2004 · N915X · Substantial damage > A blocked internal oil passage, which resulted in inadequate lubrication of the blower impeller shaft, and the subsequent partial loss of engine power. - [NTSB SEA02LA121](https://openairdocs.org/ntsb/SEA02LA121.md): Grumman-Schweizer G-164B · Shelley, ID · Accident · Minor injuries · Limited investigation · Final report · Jul 4, 2002 · N297AL · Destroyed > A loss of engine power due to the manufacturer's improperly machined threads, which prevented the cylinder base/head halves from being properly assembled, leading to fatigue propagation and the ultimate separation of the cylinder. A contributing factor was… - [NTSB FTW01LA193](https://openairdocs.org/ntsb/FTW01LA193.md): Grumman G164B · Rayville, LA · Accident · No injuries · Limited investigation · Final report · Aug 28, 2001 · N2LU · Substantial damage > the partial failure of the magneto drive coupling while maneuvering, which resulted in a loss of engine power and a forced landing. A contributing factor to the accident was the lack of suitable terrain for the forced landing. - [NTSB FTW00LA239](https://openairdocs.org/ntsb/FTW00LA239.md): Grumman-Schweizer G-164B · Kaplan, LA · Accident · No injuries · Limited investigation · Final report · Aug 21, 2000 · N6506K · Substantial damage > the failure of the supercharger during takeoff. A contributing factor was the lack of suitable terrain for the forced landing. - [NTSB CHI99LA162](https://openairdocs.org/ntsb/CHI99LA162.md): Grumman-Schweizer G-164B · Buxton, ND · Accident · No injuries · Limited investigation · Final report · May 25, 1999 · N6524K · Substantial damage > the number one cylinder's separation, the pilot's visual lookout not possible through the oil given off by the number one cylinder, and the embankment. A factor in the accident was the oil. - [NTSB CHI97LA006](https://openairdocs.org/ntsb/CHI97LA006.md): Callair B1A · Nebraska City, NE · Accident · Minor injuries · Limited investigation · Final report · Oct 9, 1996 · N6203X · Substantial damage > a supercharger bearing failure. A factor was the excessive sink rate during the forced landing. - [NTSB SEA96LA155](https://openairdocs.org/ntsb/SEA96LA155.md): Grumman G-164A · New Plymouth, ID · Accident · No injuries · Limited investigation · Final report · Jul 15, 1996 · N48442 · Substantial damage > a cracked cylinder head, which resulted in partial loss of engine power during takeoff. Factors relating to the accident were: the pilot allowed the gross weight of the airplane to be exceeded, and tall wheat (crop) in the emergency landing area. - [NTSB SEA96LA020](https://openairdocs.org/ntsb/SEA96LA020.md): Snow S2C · Dufer, OR · Accident · No injuries · Limited investigation · Final report · Nov 16, 1995 · N1694S · Substantial damage > A loss of engine power due to a cracked cylinder head. A factor was the evasive maneuver to avoid a ditch. - [NTSB SEA95LA154](https://openairdocs.org/ntsb/SEA95LA154.md): Air Tractor AT-301 · Roberts, ID · Accident · No injuries · Limited investigation · Final report · Jul 17, 1995 · N4326S · Substantial damage > A loss of engine power due to the separation of the number 3 cylinder exhaust valve rocker arm shaft from the cylinder head, which disabled movement of the exhaust valve. A factor was the lack of suitable terrain for the forced landing. - [NTSB MIA94LA218](https://openairdocs.org/ntsb/MIA94LA218.md): Grumman G-164B · Greenwood, MS · Accident · No injuries · Limited investigation · Final report · Sep 29, 1994 · N48572 · Substantial damage > The improper decision of the pilot to execute a precautionary landing to an unprepared field due to a supercharger shaft failure. - [NTSB LAX94LA313](https://openairdocs.org/ntsb/LAX94LA313.md): Schweizer G-164-A · Laton, CA · Accident · No injuries · Limited investigation · Final report · Aug 11, 1994 · N699Y · Substantial damage > failure of the No.7 cylinder for an unspecified reason. - [NTSB FTW93LA169](https://openairdocs.org/ntsb/FTW93LA169.md): Grumman G-164A · Weiner, AR · Accident · No injuries · Limited investigation · Final report · May 27, 1993 · N4593 · Substantial damage > Partial power loss due to improper installation of the linkage control bracket. A factor was the lack of suitable terrain for the forced landing. - [NTSB CHI92DTG04](https://openairdocs.org/ntsb/CHI92DTG04.md): Grumman G-164B · Grandin, ND · Accident · No injuries · Final report · Aug 14, 1992 · N48687 · Substantial damage > The cracked cylinder which resulted in a forced landing. The lack of suitable terrain on which to make an emergency landing was a factor. - [NTSB LAX91LA413](https://openairdocs.org/ntsb/LAX91LA413.md): Grumman G164A-450 · Queen Creek, AZ · Accident · Minor injuries · Limited investigation · Final report · Sep 29, 1991 · N16SS · Substantial damage > Failure of the engine cylinder, producing a loss of power. Contributing to the accident was the location of an irrigation ditch next to the landing area and a dark night light condition. - [NTSB FTW91DPG03](https://openairdocs.org/ntsb/FTW91DPG03.md): Grumman G-164A · Earle, AR · Accident · No injuries · Final report · Apr 2, 1991 · N5336 · Substantial damage > A power loss for undetrmined reasons. A factor was the muddy/soft terrain in which the forced landing was performed. - [NTSB FTW90DRD05](https://openairdocs.org/ntsb/FTW90DRD05.md): Schweizer G-164B · Reeves, LA · Accident · No injuries · Final report · Apr 13, 1990 · N48455 · Substantial damage > Loss of engine power due to a frozen rocker arm. - [NTSB MKC90LA067](https://openairdocs.org/ntsb/MKC90LA067.md): Grumman AG-CAT G-164A · Parkin, AR · Accident · No injuries · Limited investigation · Final report · Mar 17, 1990 · N5336 · Substantial damage > Total failure of the engine's master connecting rod. - [NTSB CHI89DEX06](https://openairdocs.org/ntsb/CHI89DEX06.md): Grumman G-164A · Sullivan, IN · Accident · No injuries · Final report · Aug 2, 1989 · N952X · Substantial damage > A failure of the supercharger oil seal which resulted in a partial loss of engine power during takeoff and the uncontrolled touchdown during the forced landing. Factors related to the accident were: partial failure of the supercharger and spark plub fowling. - [NTSB FTW89DRA08](https://openairdocs.org/ntsb/FTW89DRA08.md): Grumman-Schweizer G-164B · Anahuac, TX · Accident · Minor injuries · Final report · Jul 18, 1989 · N6633Q · Destroyed > Failure of the supercharger bearing. The dirt bank was a contributing factor. - [NTSB FTW89DRD09](https://openairdocs.org/ntsb/FTW89DRD09.md): Schweizer G-164A · Bunkie, LA · Accident · No injuries · Final report · Jun 23, 1989 · N602Y · Substantial damage > The loss of the number five cylinder in flight, resulting in a loss of engine RPM. The pilot misjudged the landing flare height due to obscured vision from fire and smoke and the airplane stalled and impacted the ground nose first. - [NTSB ANC88LA138](https://openairdocs.org/ntsb/ANC88LA138.md): de Havilland DHC-2 · Mcgrath, AK · Accident · No injuries · Limited investigation · Final report · Sep 16, 1988 · N98JH · Substantial damage > While cruising, the pilot-in-command experienced a rough engine and finally an unexplained power reduction to idle. He was unable to glide the float equipped airplane to a body of water and executed a forced landing on the tundra where the airplane sustained… - [NTSB ATL88DKG13](https://openairdocs.org/ntsb/ATL88DKG13.md): Grumman G-164A · Fadette, AL · Accident · No injuries · Final report · Aug 9, 1988 · N8573H · Substantial damage > The pilot reported a partial power loss during an aerial application flight. The aircraft landed in the crops. The pilot stated that he found the number 3 cylinder partially separated from the engine. - [NTSB LAX87DVA12](https://openairdocs.org/ntsb/LAX87DVA12.md): Grumman G164B · Buttonwillow, CA · Accident · No injuries · Final report · Sep 22, 1987 · N6607Q · Substantial damage > During an aerial application flight, after pulling out of a pass over a field the plt heard a loud bang followed by severe engine vibration. The acft lost power and the pilot made a forced landing in a plowed field. During the landing roll the acft nosed… - [NTSB SEA87LA111](https://openairdocs.org/ntsb/SEA87LA111.md): de Havilland DHC-2 MK.1 · Sedro Woolley, WA · Accident · Minor injuries · Limited investigation · Final report · Jun 8, 1987 · N64384 · Destroyed > Shortly after takeoff a loss of power occurred and the aircraft struck trees in flight. Less than 1/2 fuel was available in all three fuel tanks. The fuel selector valve was tested and found that the selections plate was indexed off center for all selections… - [NTSB FTW87DRA03](https://openairdocs.org/ntsb/FTW87DRA03.md): Grumman G-164B · Egypt, TX · Accident · No injuries · Final report · Jun 8, 1987 · N6667Q · Substantial damage > Acft experienced a power loss drng an aerial app maneuver. During the ensuing emerg lndg, the left wing struck high weeds on the shoulder of a road, veered left into a ditch, and flipped over. Investigation revealed no. 7 cylinder had a pre-existing crack in… - [NTSB MKC87LA028](https://openairdocs.org/ntsb/MKC87LA028.md): Grumman-Schweizer G-164B-600 · Earle, AR · Accident · No injuries · Limited investigation · Final report · Dec 3, 1986 · N6898Q · Substantial damage > The pilot stated that the powerplant was performing normally during initial climb when, suddenly, the engine experienced a power loss after backfiring. Immediate remedial action resulted in a partial power output but not enough to sustain flight. Emergency… - [NTSB FTW86LA160](https://openairdocs.org/ntsb/FTW86LA160.md): Boeing E75 · Sweetwater, TX · Accident · No injuries · Limited investigation · Final report · Sep 2, 1986 · N4563N · Substantial damage > While the acft was in cruise flt, the engine suddenly went to idle power. The plt attempted to land in a clearing, but was unable to reach the intended area. During the landing, the acft collided with low mesquite trees, damaging the landing gear & wings. An… - [NTSB FTW86LRD12](https://openairdocs.org/ntsb/FTW86LRD12.md): Grumman G-164A · Branch, LA · Accident · No injuries · Final report · May 21, 1986 · N5407 · Substantial damage > Shortly after takeoff, a partial power loss occurred & the plt made a forced landing in a soft plowed field, where the acft nosed over onto its back. The plt rprtd the loss of power was due to failure of the eng blower. - [NTSB MKC86LA086](https://openairdocs.org/ntsb/MKC86LA086.md): Grumman G164B · Advance, MO · Accident · No injuries · Limited investigation · Final report · Apr 12, 1986 · N6609Q · Substantial damage > The airplane was being operated as an agricultural aircraft when the engine started backfiring and then quit. During the forced landing in a plowed field, the airplane flipped forward to the inverted position. Investigation revealed the teeth on the left… - [NTSB FTW86FA004](https://openairdocs.org/ntsb/FTW86FA004.md): Beech H18 · Oklahoma City, OK · Accident · 2 fatal · Field investigation · Final report · Nov 5, 1985 · N1461G · Destroyed > Atr plt departing arpt under VMC experienced failure of the right eng shortly after lift-off. The acft yawed right followed by a steep right roll, contacting power lines with the right wing and subsequently impacted the ground. A post-crash fire destoyed the… - [NTSB SEA85LA076](https://openairdocs.org/ntsb/SEA85LA076.md): Weatherly 201B · Davenport, WA · Accident · No injuries · Limited investigation · Final report · Mar 15, 1985 · N1263W · Substantial damage > A vibration started in the engine and while the plt was monitoring the engine gauges he noted a loss of all oil pressure. A landing was made on a field and during rollout the left main gear was torn off when it struck a mound of dirt. The acft then struck… - [NTSB FTW85LA002](https://openairdocs.org/ntsb/FTW85LA002.md): Grumman G-164A · Progreso, TX · Accident · No injuries · Limited investigation · Final report · Oct 1, 1984 · N5255 · Substantial damage > Shortly after takeoff, plt heard explosive report from engine and experienced partial pwr loss. Plt attempted to return for landing but could not maintain sufficient altitude. Load not jettisoned. During forced landing roll out in cane field acft nosed over.… - [NTSB DEN84LA270](https://openairdocs.org/ntsb/DEN84LA270.md): Weatherly 201B · Grand Forks, ND · Accident · No injuries · Limited investigation · Final report · Aug 27, 1984 · N1268W · Substantial damage > During initial takeoff climb at an alt of aprx 100 ft AGL, engine began missing. Unable to maintain alt, forced landing was made in a plowed field during which landing gear was torn from the acft. Inspection revealed #5 cylinder head separated from the… - [NTSB DEN84LA245](https://openairdocs.org/ntsb/DEN84LA245.md): Consolidated-Vultee BT-13B · Hobbs, NM · Accident · No injuries · Limited investigation · Final report · Jul 28, 1984 · N63697 · Substantial damage > As part of a group of a confederate air force acft the flight conducted public relations flyovers at several area arpts. Due to a low ldg gear strut N63697 did not land with the other acft after the flyovers. The plt planned to have the strut repaired upon… - [NTSB FTW83LA405](https://openairdocs.org/ntsb/FTW83LA405.md): Grumman G-164B · East Bernard, TX · Accident · Minor injuries · Limited investigation · Final report · Aug 31, 1983 · N48687 · Substantial damage > During takeoff, the eng had a partial loss of power after the acft lifted off. The plt reported that he dumped his load of defoliant, but the acft would not climb. Subsequently, it settled & collided with brush & trees. The plt attributed the power loss to a… - [NTSB ATL83LA348](https://openairdocs.org/ntsb/ATL83LA348.md): Grumman G-164A · Clinton, KY · Accident · No injuries · Limited investigation · Final report · Aug 31, 1983 · N5256 · Substantial damage > The plt reported that he was spraying a field that was bordered by obstacles. When he was about half way thru a procedure turn, the eng began 'backfiring & losing power.' The plt moved the throttle to about the 1/2 power setting, hoping the condition would be… - [NTSB MIA83LA179](https://openairdocs.org/ntsb/MIA83LA179.md): Grumman G-164B · Altha, FL · Accident · No injuries · Limited investigation · Final report · Jul 1, 1983 · N6531K · Substantial damage > The plt stated that the eng began losing power during an aerial application mission. Subsequently, he landed in a muddy field & the acft nosed over. He stated that the indupartial loss of power. - [NTSB FTW82DA250](https://openairdocs.org/ntsb/FTW82DA250.md): Beech D18S · Belen, NM · Accident · No injuries · Final report · Jun 26, 1982 · N3962 · Substantial damage > The pilot stated that during flight, the left engine began leaking oil and the cockpit filled with smoke. He shut down the left engine, but stated that the propeller would not completely feather due to the loss of oil. While approaching to land at a nearby… - [NTSB FTW82DA211](https://openairdocs.org/ntsb/FTW82DA211.md): Beech D18S · Beeville, TX · Accident · No injuries · Final report · Jun 3, 1982 · N7510 · Substantial damage > The pilot and three passengers departed on a pleasure flight. The pilot stated that after climbing several hundred feet and while at 110 mph, the right propeller went into high pitch following a propeller governor failure. This resulted in a loss of engine… - [NTSB MKC82DA085](https://openairdocs.org/ntsb/MKC82DA085.md): Grumman G-164A · Tekamah, NE · Accident · No injuries · Final report · May 20, 1982 · N7689 · Substantial damage > On the third spray run the pilot stated that the aircraft engine had a loss of power. He attempted to fly back to the airport but was forced to make an emergency landing in an open field. During the landing roll the aircraft nosed over in the soft mud. Engine… ## The whole list in SQL Runs in DuckDB 1.2 or later on the release's Parquet files over HTTPS: ```sql SELECT c."ntsbNumber", c."eventDate", c."eventType", c."eventCity", c."eventStateOrRegion", a.n_number, a."aircraftMake", a."aircraftModel", c."highestInjuryLevel", c."totalFatal", c."completionStatus", c.report_url FROM 'https://openairdocs.org/data/latest/ntsb_case_detail.parquet' c LEFT JOIN 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' a ON a.case_mkey = c."mKey" AND a.position = 1 WHERE c."mKey" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('52008') AND EXISTS (SELECT 1 FROM 'https://openairdocs.org/data/latest/ntsb_occurrences.parquet' o WHERE o.case_mkey = x.case_mkey AND o.aircrafts_position = x.position AND o."occurrenceNumber" = 1 AND o."occurrenceCode" = 352)) ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC ``` This list as a web page: https://openairdocs.org/ntsb?engine=52008&occurrence=352 --- 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.