# NTSB CHI90LA220: Schleicher ASK-21, N342KS, Plainfield, IL, July 31, 1990

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: July 31, 1990, 13:00 local (18:00 UTC)
- Place: Plainfield, IL
- Coordinates: 41.610343, -88.199317 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=41.6103&lon=-88.1993&mi=10
- Phase of flight: [Emergency descent](https://openairdocs.org/ntsb-phases/600) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report November 9, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 14742
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI90LA220
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/14742/pdf
- Page: https://openairdocs.org/ntsb/CHI90LA220

## Probable cause

THE GLIDER PILOT'S IMPROPER AIRCRAFT HANDLING AT LOW ATITUDE.

## Sequence of events

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

- In flight collision with object, descent - emergency
  - aircraft handling - improper, pilot in command (cause)
  - glider/tow release - performed, pilot in command (contributing factor)
  - clearance - not maintained, pilot in command (cause)
- In flight collision with terrain/water, landing - flare/touchdown
  - terrain condition - crop

## Analysis

THE GLIDER PILOT STATED THAT HE ALLOWED HIS AIRCRAFT TO GET OUT OF POSITION BEHIND THE TOW PLANE DURING INITIAL CLIMBOUT. HE REPORTED THAT HE WAS AFRAID THE TOW LINE WOULD PULL THE TOW PLANE OUT OF CONTROL AT LOW ALTITUDE, SO HE RELEASED AND ATTEMPTED TO RETURN TO THE DEPARTURE AIRPORT FOR A LANDING. THE GLIDER IMPACTED TREES ON THE EDGE OF THE AIRPORT AND CAME TO REST IN A BEAN FIELD.

## Aircraft

- Registration: N342KS (not matched to a registry record)
- Reported make and model: SCHLEICHER ASK-21
- Category: Glider
- Serial number: 21253
- Engines: unknown
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Advanced Soaring Klub, Ltd.
- Registered owner: Advanced Soaring Klub, Ltd.
- Airworthiness certificate: Standard, Normal
- Airport: 1C5, Clow International

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 64; commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: front; flight hours: 1,316 total, 8 in this make and model, 1,123 as pilot in command, 21 in the last 90 days, 6 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 20° at 10 knots
- Visibility: 20 statute miles
- Lowest ceiling: 3,000 ft broken
- Temperature: 70 °F, dew point 54 °F
- Altimeter: 30.00 inHg
- Observed at: ARR

## 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 19900731029339A](https://openairdocs.org/incident/19900731029339A), Jul 31, 1990: Schler ASK21, Plainfield, IL, Substantial damage. Too wide and too much slack in tow. Cut loose from tow plane and landed in trees.

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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