# NTSB CHI88DEE05: Weatherly 620, N4605P, Dekalb, IL, July 11, 1988

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Final report
- Date: July 11, 1988, 15:00 local (20:00 UTC)
- Place: Dekalb, IL
- Coordinates: 41.890525, -88.750625 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=41.8905&lon=-88.7506&mi=10
- Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report July 9, 1990
- Report: Approved by Office Director
- NTSB case key (mKey): 13855
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI88DEE05
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/13855/pdf
- Page: https://openairdocs.org/ntsb/CHI88DEE05

## Probable cause

AN ON GROUND ENCOUNTER WITH WEATHER.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Loss of control - on ground/water, takeoff
  - weather condition - windshear (contributing factor)
  - directional control - not maintained, pilot in command (cause)
  - compensation for wind conditions - improper, pilot in command (cause)

## Analysis

ON TAKEOFF ROLL, JUST PRIOR TO RAISING THE TAIL, THE AIRPLANE ENCOUNTERED A DUST DEVIL. THE PLT SAID HE LOST DIRECTIONAL CONTROL AND THE AIRPLANE DEPARTED THE RUNWAY AND COLLIDED WITH A GROVE OF TREES.

## Aircraft

- Registration: [N4605P](https://openairdocs.org/deregistered/N4605P-1994-07-13), registration cancelled 1994-07-13, S/N 1507 (OpenAirDocs)
- Reported make and model: WEATHERLY 620
- Registry model: [Weatherly 620](https://openairdocs.org/model/weatherly-620) (registry code 9630602) (OpenAirDocs)
- Category: Airplane
- Serial number: 1507
- Airframe hours: 1620
- Engines: P&W R985-AA-1 450 horsepower reciprocating
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Operator: Gulf Flying Service
- Registered owner: Sam Styron
- Airworthiness certificate: Special, Restricted (Special)
- Last inspection: Annual, February 7, 1988, 125 hours before
- Airport: DKB, Dekalb, runway 9, 3,500 × 50 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 65; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: center; flight hours: 29,000 total, 80 in this make and model, 19,500 as pilot in command, 80 in the last 90 days, 40 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 84 °F
- Altimeter: 30.00 inHg

## 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 19880711026219A](https://openairdocs.org/incident/19880711026219A), Jul 11, 1988: Wthrly 620, Dekalb, IL, Substantial damage. Struck trees after takeoff. Blamed windshear. Numerous dust devils in area.

## Other investigations on N4605P (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 CHI93DEE05](https://openairdocs.org/ntsb/CHI93DEE05), Aug 14, 1993: Weatherly 620 (N4605P), Mendota, IL, destroyed. Probable cause: THE PILOT-IN-COMMAND'S FAILURE TO MAINTAIN CLEARANCE FOM POWERLINES DURING AN AERIAL APPLICATION MANUEVER.

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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