# NTSB CHI84LA130: Cessna 401, N777CS, Chicago, IL, March 15, 1984

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: March 14, 1984, 22:30 local (Mar 15, 1984, 04:30 UTC)
- Place: Chicago, IL
- Coordinates: 41.780445, -87.769027 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=41.7804&lon=-87.7690&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 12561
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI84LA130
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/12561/pdf
- Page: https://openairdocs.org/ntsb/CHI84LA130

## Sequence of events

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

- Main gear collapsed, landing - roll
  - landing gear,main gear attachment - failure,total (cause)
  - maintenance - poor, company maintenance personnel (cause)

## Analysis

THE ACFTS LEFT MAIN GEAR COLLAPSED DURING THE LANDING ROLL. INVESTIGATION REVEALED THAT THE BOLT ON THE TOP PORTION OF THE LH BELLCRANK ASSEMBLY WAS SHEARED OFF. ONE OF THE TANGS AT THE BOTTOM OF THE BELLCRANK WAS ALSO BROKEN. WHEN EXAMINED UNDER A 10 POWER MICROSCOPE THE FRACTURED REVEALED INSTANTANEOUS OVERLOAD CHARACTERISTICS.

## Aircraft

- Registration: [N777CS](https://openairdocs.org/deregistered/N777CS-1989-10-27), registration cancelled 1989-10-27, S/N 4010152 (OpenAirDocs)
- Reported make and model: CESSNA 401
- Registry model: [Cessna 401](https://openairdocs.org/model/cessna-401) (registry code 207590C) (OpenAirDocs)
- Category: Airplane
- Serial number: 4010152
- Airframe hours: 4855
- Engines: Continental TSIO-520-E 300 horsepower reciprocating
- Damage: Substantial damage
- Flight: Part 135
- Registered owner: Midwest Aviation Corp.
- Airworthiness certificate: Standard, Normal
- Last inspection: 100 hour, March 6, 1984, 11 hours before
- Departed: MSN, MADISON, WI
- Flight plan: IFR
- Airport: MDW, Midway, runway 13R, 6,519 × 175 ft, concrete

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; airline transport, commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: right; flight hours: 8,326 total, 436 in this make and model, 8,219 as pilot in command, 143 in the last 90 days, 2 in the last 24 hours

## Weather

- Conditions: Instrument (IMC), Night/dark
- Wind: 170° at 14 knots, gusting 19
- Visibility: 2 statute miles
- Lowest ceiling: 600 ft overcast
- Temperature: 34 °F, dew point 28 °F
- Altimeter: 30.00 inHg
- Observed at: MDW

## 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 19840314031529A](https://openairdocs.org/incident/19840314031529A), Mar 14, 1984: Cessna 401, Chicago, IL, Substantial damage. Left main landing gear collapse on the landing roll. Broken bellcrank indicates overload damage.

## Other investigations on N777CS (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 CHI86LA085](https://openairdocs.org/ntsb/CHI86LA085), Feb 9, 1986: Cessna 401B (N777CS), Milwaukee, WI, substantial damage

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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