# NTSB ERA17LA249: Grumman G 164, N691Y, Marydel, DE, July 19, 2017

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Limited investigation · Final report
- Date: July 19, 2017, 09:21 local (13:21 UTC)
- Place: Marydel, DE
- Coordinates: 39.050873, -75.71832 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=39.0509&lon=-75.7183&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Defining event: [Maneuvering: Low altitude operation/event](https://openairdocs.org/ntsb-events/220)
- Highest injury: Serious injuries
- Injuries: 1 serious
- Status: Completed, report April 8, 2019
- Report: Approved by Office Director
- NTSB office: Eastern Region Aviation
- Parties: FAA/FSDO
- NTSB case key (mKey): 95608
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA17LA249
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/95608/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=95608
- Page: https://openairdocs.org/ntsb/ERA17LA249

## Probable cause

The pilot's failure to maintain adequate clearance from power lines while conducting an aerial application flight.

## Findings

NTSB's coded findings; those marked are part of the probable cause.

- [Attention/monitoring: monitoring environment](https://openairdocs.org/ntsb-findings/02021545): Personnel issues › Psychological · Pilot (probable cause); cases with it: [Grumman G-164, 1 case](https://openairdocs.org/ntsb-findings/02021545/cases.md?model=3952702), [All aircraft, 809 cases](https://openairdocs.org/ntsb-findings/02021545/cases.md)
- [Performance/control parameters: altitude](https://openairdocs.org/ntsb-findings/01062012): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Grumman G-164, 1 case](https://openairdocs.org/ntsb-findings/01062012/cases.md?model=3952702), [All aircraft, 1,310 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md)
- [Object/animal/substance: tower/antenna (incl guy wires)](https://openairdocs.org/ntsb-findings/03022017): Environmental issues › Physical environment · Effect on equipment (probable cause); cases with it: [Grumman G-164, 1 case](https://openairdocs.org/ntsb-findings/03022017/cases.md?model=3952702), [All aircraft, 55 cases](https://openairdocs.org/ntsb-findings/03022017/cases.md)

## Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event best describes what happened.

- [Maneuvering: Low altitude operation/event](https://openairdocs.org/ntsb-events/220) (defining event); cases with it: [Grumman G-164, 2 cases](https://openairdocs.org/ntsb-events/220/sequence.md?model=3952702), [All aircraft, 780 cases](https://openairdocs.org/ntsb-events/220/sequence.md)
- [Maneuvering-low-alt flying: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Grumman G-164, 5 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=3952702), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md)
- [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Grumman G-164, 5 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=3952702), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md)

## Analysis

The commercial pilot was performing an aerial application flight. He had just completed his first pass spraying a field when the airplane struck a set of power lines and impacted a field adjacent to the field that he was spraying, which resulted in substantial damage to the fuselage and both wings. The pilot stated that he had no memory of the accident. Review of data downloaded from an onboard GPS unit was consistent with the airplane operating normally as it made a pass over the field and then initiating a climb near the power lines. The recorded data ended shortly after the airplane was on the opposite side of the power lines.

## Factual narrative

On July 19, 2017, about 0921 eastern daylight time, a Grumman G164 airplane, N691Y, was substantially damaged when it struck power lines and impacted a field while spraying a field near Marydel, Delaware. The commercial pilot was seriously injured. The airplane was registered to and operated by Air Enterprises, Inc., as a Title 14 Code of Federal Regulations Part 137 aerial application flight. Visual meteorological conditions prevailed at the accident site and no flight plan was filed for the flight that departed Johnson's Airport (DE09), Magnolia, Delaware, about 0910.According to the operator, the pilot had completed two spray runs and had returned to DE09 to reload. He then departed for his third spray run when the airplane struck a set of four power lines and impacted terrain after completing the first pass of the field. In an interview, the pilot told a Federal Aviation Administration (FAA) inspector that he did not remember anything about the accident. Postaccident examination revealed the airplane impacted a field adjacent to the field he was spraying and sustained substantial damage to both wings and the fuselage. There was no postimpact fire. Data downloaded from the onboard AgNav P151 GPS revealed the airplane approached the field on a westerly heading, passed low over the field as the sprayer was turned on then off, before it began a climb near the power lines. The airplane continued to travel west until data stopped at 0921 when the airplane was on the opposite side of the power lines. The pilot held a commercial pilot certificate with ratings for airplane single-engine land, and instrument airplane. His last FAA second-class medical certificate was issued on March 7, 2017. The pilot reported a total of 913 hours, with 63 hours in the same make/model as the accident airplane. Weather reported at Dover Air Force Base (DOV), Dover, Delaware, about 10 miles southeast of the accident site, at 0858, was wind from 200° at 5 knots, visibility 10 miles and clear skies. The temperature was 27° C and the dew point was also 27° C.

## Aircraft

- Registration: [N691Y](https://openairdocs.org/deregistered/N691Y-2019-03-12), registration cancelled 2019-03-12, S/N 242, built 1964 (OpenAirDocs)
- Reported make and model: GRUMMAN G 164 (UNDESIGNAT)
- Registry model: [Grumman G-164](https://openairdocs.org/model/grumman-g-164) (registry code 3952702) (OpenAirDocs)
- Registry engine: [Continental W670 series](https://openairdocs.org/engine/continental-w670-series) (registry code 17018, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 242
- Year built: 1964
- Airframe hours: 9490.1
- Engines: Pratt&Whitney R-985 450 horsepower reciprocating
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Airworthiness certificate: Special, Restricted (Special); Standard, Utility
- Last inspection: Annual, August 2, 2016
- Departed: DE09, Magnolia, DE
- Destination: None, Marydel, DE
- Equipment: Data recorder

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 52; injuries: serious; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, with waivers/limitations; seat: center; restraint: 5-point; toxicology performed; flight hours: 913 total, 63 in this make and model

## Weather

- Conditions: Visual (VMC), Day
- Wind: 200° at 5 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 81 °F, dew point 81 °F
- Altimeter: 30.05 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 20170719010739A](https://openairdocs.org/incident/20170719010739A), Jul 19, 2017: Grumman G-164, Marydel, DE, Destroyed. The aircraft was completing the first pass of third flight, appeared to be at a normal speed and altitude for a standard spraying pass when it struck power…

## Docket (8 files)

The files NTSB released with the investigation on December 12, 2018, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=95608. 5.1 MB in all.

- Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 840 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469331&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF
- Excerpt of FAA Inspector's Interview with the Pilot (item 2, .PDF, 104 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469332&FileExtension=.PDF&FileName=Excerpt%20of%20FAA%20Inspector%27s%20Interview%20with%20the%20Pilot-Master.PDF
- Maintenance Records (item 3, .PDF, 360 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469333&FileExtension=.PDF&FileName=Maintenance%20Records-Master.PDF
- Toxicological Report (item 4, .PDF, 279 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469334&FileExtension=.PDF&FileName=Toxicological%20Report-Master.PDF
- Photos (item 5, .PDF, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469335&FileExtension=.PDF&FileName=Photos-Master.PDF
- Global Positioning System (GPS) Device - Factual Report (item 6, .PDF, 1.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469336&FileExtension=.PDF&FileName=Global%20Positioning%20System%20(GPS)%20Device%20-%20Factual%20Report-Master.PDF
- Attachment 1 to Global Positioning System (GPS) Device - Factual Report (item 7, .CSV, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469337&FileExtension=.csv&FileName=Attachment%201%20to%20Global%20Positioning%20System%20(GPS)%20Device%20-%20Factual%20Report-Master.csv
- Evidence Control Form (item 8, .PDF, 76 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40469338&FileExtension=.PDF&FileName=Evidence%20Control%20Form-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.

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