# NTSB ERA14LA321: Grumman Acft ENG Cor-Schweizer G 164B, N891JC, Farmington, DE, June 18, 2014 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: June 18, 2014, 19:30 local (23:30 UTC) - Place: Farmington, DE - Coordinates: 38.843055, -75.60778 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=38.8431&lon=-75.6078&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Defining event: [Initial climb: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report June 1, 2015 - Report: Approved by Office Director - NTSB office: Eastern Region Aviation - Parties: Covington Aircraft Engines, Inc., FAA/FSDO - NTSB case key (mKey): 89580 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA14LA321 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/89580/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=89580 - Page: https://openairdocs.org/ntsb/ERA14LA321 ## Probable cause The pilot's inadequate preflight planning for a takeoff in high-density altitude conditions and his decision to reduce power during the initial climb, which led to the airplane exceeding its critical angle-of-attack and experiencing an aerodynamic stall. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Grumman Acft ENG Cor-Schweizer G-164B, 11 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=3952802), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Performance/control parameters: angle of attack](https://openairdocs.org/ntsb-findings/01062042): Aircraft › Aircraft oper/perf/capability · Capability exceeded (probable cause); cases with it: [Grumman Acft ENG Cor-Schweizer G-164B, 2 cases](https://openairdocs.org/ntsb-findings/01062042/cases.md?model=3952802), [All aircraft, 990 cases](https://openairdocs.org/ntsb-findings/01062042/cases.md) - [Performance/control parameters: airspeed](https://openairdocs.org/ntsb-findings/01062010): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Grumman Acft ENG Cor-Schweizer G-164B, 5 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md?model=3952802), [All aircraft, 1,681 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md) - [Temp/humidity/pressure: high density altitude](https://openairdocs.org/ntsb-findings/03031020): Environmental issues › Conditions/weather/phenomena · Effect on equipment; cases with it: [Grumman Acft ENG Cor-Schweizer G-164B, 3 cases](https://openairdocs.org/ntsb-findings/03031020/cases.md?model=3952802), [All aircraft, 278 cases](https://openairdocs.org/ntsb-findings/03031020/cases.md) - [Planning/preparation: flight planning/navigation](https://openairdocs.org/ntsb-findings/02061025): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Grumman Acft ENG Cor-Schweizer G-164B, 1 case](https://openairdocs.org/ntsb-findings/02061025/cases.md?model=3952802), [All aircraft, 179 cases](https://openairdocs.org/ntsb-findings/02061025/cases.md) - [Info processing/decision: decision making/judgment](https://openairdocs.org/ntsb-findings/02041520): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Grumman Acft ENG Cor-Schweizer G-164B, 6 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md?model=3952802), [All aircraft, 3,098 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Initial climb: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241) (defining event); cases with it: [Grumman Acft ENG Cor-Schweizer G-164B, 4 cases](https://openairdocs.org/ntsb-events/241/sequence.md?model=3952802), [All aircraft, 1,529 cases](https://openairdocs.org/ntsb-events/241/sequence.md) - [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Grumman Acft ENG Cor-Schweizer G-164B, 21 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=3952802), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) - [Landing-landing roll: Nose over/nose down](https://openairdocs.org/ntsb-events/096); cases with it: [Grumman Acft ENG Cor-Schweizer G-164B, 19 cases](https://openairdocs.org/ntsb-events/096/sequence.md?model=3952802), [All aircraft, 2,287 cases](https://openairdocs.org/ntsb-events/096/sequence.md) ## Analysis The pilot reported that the takeoff was normal for the agricultural flight and that he subsequently reduced the manifold pressure to 32 inches and the propeller speed to about 2,000 rpm. After the airplane reached about 150 ft above ground level during the climbout, he commanded a left bank, and the airplane immediately began to "settle." He rolled the airplane to a wings-level attitude; however, the airplane subsequently made an uncommanded right roll, which he described as "similar to entering a stall." He attempted to activate the product "dump" handle; however, he inadvertently activated the "spray" handle. He again attempted to activate the "dump" handle; however, due to the airplane's low altitude, he did not have time to do so, and the airplane then impacted terrain. Examination of the engine revealed that the intermediate gear had three teeth sheared off; however, this likely occurred during the accident sequence and did not contribute to the accident. No other preimpact abnormalities that would have precluded normal operation were noted. Although the airplane was below its maximum takeoff weight, the density altitude around the time of the accident was calculated to be about 2,100 ft, which would have decreased the airplane's climb rate by about 20 percent. Therefore, it is likely that the decreased climb rate, the pilot-commanded reduction in engine power, and the loss of lift developed during the left bank led to the airplane exceeding its critical angle-of-attack and then experiencing an aerodynamic stall at too low an altitude for the pilot to affect a recovery before the airplane impacted the ground. Although it is possible that the pilot reapplied full power following the first indication of a stall, he was likely more focused on unloading the product to reduce the total weight of the airplane than on recovering from the stall. ## Factual narrative HISTORY OF FLIGHT On June 18, 2014, about 1930 eastern daylight time, a Grumman Aircraft G-164B, N891JC, impacted the ground during a forced landing shortly after takeoff near Chorman Airport (D74), Farmington, Delaware. The airplane was owned and operated by Chorman Spraying, LLC as an aerial application flight. The commercial pilot received minor injuries and the airplane sustained substantial damage to the fuselage and empennage. Visual meteorological conditions prevailed and no flight plan had been filed for the local flight, which was operated under the provisions of Title 14 Code of Federal Regulations Part 137. The flight was originating at the time of the accident. According to the pilot, he flew the airplane in the morning and returned to the airport about 1900, to load the hopper tank with insecticide and water, for a flight to a nearby watermelon farm. After loading the product and fueling the airplane, he taxied out, performed the required pre-takeoff checklist items, and departed to the north. After departure, he maneuvered the airplane in order to climb out to the right of the runway's extended centerline to avoid overflying a residence. He further reported that he reduced the manifold pressure back to 32 inches and the propeller speed to about 2,000 rpm. Approximately 150 feet above ground level, he commanded a slight left bank towards the west and immediately the airplane started to "settle." The pilot leveled the wings; however, the airplane started an uncommanded right bank "similar to entering a stall." He attempted to pull the product "dump" handle, but inadvertently activated the "spray" handle. He then attempted to pull the dump handle again, but was unable to do so due to the airplane's close proximity to the ground. The airplane subsequently impacted a field, nosed over, and came to rest inverted. PERSONNEL INFORMATION According to the pilot and Federal Aviation Administration (FAA) records, the pilot held a commercial pilot certificate with a rating for airplane single-engine land, multiengine land, and instrument airplane. He also held a flight instructor certificate for airplane single and multiengine land, and instrument airplane. The pilot's most recent second-class medical certificate was issued on October 24, 2013. According to the pilot, he had accumulated 2,306 hours of total flight time and 573 hours of flight time in the accident airplane make and model. AIRCRAFT INFORMATION According to the pilot and the operator's records, the single-engine, tailwheel-equipped biplane was manufactured in 1977. It was powered by a Pratt and Whitney radial engine with 10,125 hours of time in service and 553.53 hours since major overhaul. The most recent annual inspection was recorded on May 8, 2014. METEROGOLOGICAL INFORMATION The 1854 recorded weather observation at Sussex County Airport (GED), Georgetown, Delaware, located 15 miles to the southeast of the accident location, included wind from 210 degrees at 8 knots,visibility 10 miles, clear skies, temperature 33 degrees C, dew point 20 degrees C; barometric altimeter 29.96 inches of mercury. The density altitude was about 2,100 feet. AIRPORT INFORMATION The airport was a privately owned airport and at the time of the accident did not have a control tower. It was equipped with a single runway designated 16/34. The runway was 3,588 feet long and 37 feet wide and the runway surface was considered "in poor condition." The airport elevation was 66 feet above mean sea level. WRECKAGE AND IMPACT INFORMATION Examination of the airplane by a FAA inspector, following the airplane's recovery from the field, revealed that the airplane's fuselage, vertical stabilizer, and rudder were substantially damaged. Rotation of the engine, by hand, was accomplished utilizing the propeller hub, which revealed continuity through the engine and thumb compression on some of the cylinders. However, there was no rotation through the supercharger and the impeller was not rotating. TEST AND RESEARCH The engine was examined, under the supervision of the NTSB Investigator-in-Charge, and during the examination the engine was noted as exhibiting minimal damage. When the engine was rotated by hand, utilizing a crankshaft turning bar, some internal binding was noted and the impeller did not rotate. Thumb compression was observed on all cylinders. Due to the internal binding, an engine run was not possible and the engine was disassembled. During the disassembly it was noted that the intermediate gear had three teeth that were impact sheared, and further examination of the gear revealed no other damage. Examination of the engine revealed no evidence of preimpact anomalies that would have precluded normal operation. For a detailed report on the engine examination refer to the public docket for this accident. ADDITIONAL INFORMATION According to the pilot and operator, the airplane was fueled with 80 gallons of fuel and had 250 gallons of product in the forward hopper tank, just prior to departure. The airplane weight at the time of the accident was about 6,934 pounds, and the maximum gross weight for the airplane was 7,564 pounds. Density Altitude Pilot's Handbook of Aeronautical Knowledge (FAA-H-8083-25A) noted that density altitude represents pressure altitude corrected for nonstandard temperature. A decrease in air density corresponds with an increase in density altitude and a decrease in airplane performance. Density altitude is used in calculating airplane performance. FAA Pamphlet FAA-P-8740-2 (2008), "Density Altitude," defines density altitude as "pressure altitude corrected for non-standard temperature variations." Density altitude can affect aircraft performance. As density altitude increases, air density decreases, which results in decreased aircraft performance. According to the Koch chart on page 3 of the pamphlet, and based on the conditions at the time of the accident, 91 degrees F and pressure altitude of about sea level, theairplane's climb rate would have been reduced by about 20 percent. ## Aircraft - Registration: [N891JC](https://openairdocs.org/deregistered/N891JC-2015-02-23), registration cancelled 2015-02-23, S/N 193B, built 1977 (OpenAirDocs) - Reported make and model: GRUMMAN ACFT ENG COR-SCHWEIZER G 164B - Registry model: [Grumman Acft ENG Cor-Schweizer G-164B](https://openairdocs.org/model/grumman-acft-eng-cor-schweizer-g-164b) (registry code 3952802) (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: 193B - Year built: 1977 - Airframe hours: 12108 - Engines: Pratt and Whitney R-1340-AN1 600 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Chorman Spraying LLC - Registered owner: Chorman Spraying LLC - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, May 8, 2014, 146 hours before - Departed: D74, Farmington, DE - Destination: D74, Farmington, DE - Airport: D74, Chorman, runway 34, 3,588 × 37 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 42; injuries: minor; flight instructor, commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, without waivers/limitations; last flight review February 22, 2013; seat: single; restraint: 3-point; flight hours: 2,306 total, 573 in this make and model, 2,197 as pilot in command, 76 in the last 90 days, 76 in the last 30 days, 7 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 210° at 8 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 91 °F, dew point 68 °F - Altimeter: 29.95 inHg - Observed at: KGED, 15 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 20140618014639A](https://openairdocs.org/incident/20140618014639A), Jun 18, 2014: Grumman Acft Eng Cor-Schweizer G-164B, Milton, DE, Substantial damage. Pilot departed rwy 34 at D74 with a full load of fuel and a 250 gallon load. Mixture -195 water/ 55 pounds of chemicals - brigade/kociee (spraying watermelons)… ## Docket (10 files) The files NTSB released with the investigation on April 2, 2015, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=89580. 9.7 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 2.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40424508&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Engine Examination (item 2, .PDF, 16 photos, 4.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40424509&FileExtension=.PDF&FileName=Engine%20Examination-Redacted.PDF - Maintenance Records [Excerpts] (item 3, .PDF, 579 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40424510&FileExtension=.PDF&FileName=Maintenance%20Records%20%5BExcerpts%5D-Redacted.PDF - Memorandum of Record – GED Weather (item 4, .PDF, 118 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40424511&FileExtension=.PDF&FileName=Memorandum%20of%20Record%20%E2%80%93%20GED%20Weather-Master.PDF - Koch Chart with Markup (item 5, .PDF, 500 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40424512&FileExtension=.PDF&FileName=Koch%20Chart%20with%20Markup-Master.PDF - Statement of Party Representatives (item 6, .PDF, 370 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40424513&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives-Redacted.PDF - Email of Factual to Party Member (item 7, .PDF, 111 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40424514&FileExtension=.PDF&FileName=Email%20of%20Factual%20to%20Party%20Member-Redacted.PDF - Photo 1 - Post Recovery (Photo Courtesy of FAA) (item 8, .PDF, 694 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40424515&FileExtension=.PDF&FileName=Photo%201%20-%20Post%20Recovery%20(Photo%20Courtesy%20of%20FAA)-Master.PDF - Photo 2 - Rudder Damage (Photo Courtesy of FAA) (item 9, .PDF, 632 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40424516&FileExtension=.PDF&FileName=Photo%202%20-%20Rudder%20Damage%20(Photo%20Courtesy%20of%20FAA)-Master.PDF - Photo 3 - Tachometer as Found Post Recovery (Photo Courtesy of FAA) (item 10, .PDF, 293 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40424517&FileExtension=.PDF&FileName=Photo%203%20-%20Tachometer%20as%20Found%20Post%20Recovery%20(Photo%20Courtesy%20of%20FAA)-Master.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.