# NTSB FTW83LA435: Pitts S-1T, N49311, Haskell, OK, September 18, 1983

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: September 18, 1983, 14:30 local (19:30 UTC)
- Place: Haskell, OK
- Coordinates: 35.820583, -95.669586 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=35.8206&lon=-95.6696&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 21057
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW83LA435
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/21057/pdf
- Page: https://openairdocs.org/ntsb/FTW83LA435

## Sequence of events

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

- Airframe/component/system failure/malfunction, maneuvering
  - aerobatics - performed, pilot in command
  - engine assembly,crankshaft - fatigue (cause)
  - propeller system/accessories - separation
- Forced landing, landing
- On ground/water collision with object, landing - roll
  - object - building(nonresidential) (contributing factor)

## Analysis

WHILE PERFORMING A SNAPROLL AT AN AIRSHOW, THE CRANKSHAFT FAILED & THE PROP SEPARATED FROM THE ACFT. THE PLT LANDED ON THE ARPT, BUT THE ACFT WENT THRU AN OPEN HANGER BEFORE THE PLT COULD STOP. THE WINGS STRUCK SUPPORTING POLES UNDER THE ROOF OF THE HANGER. AN EXAM REVEALED THAT THE CRANSHAFT HAD FAILED FROM FATIGUE.

## Aircraft

- Registration: N49311 (not matched to a registry record)
- Reported make and model: PITTS S-1T
- Category: Airplane
- Serial number: 007
- Airframe hours: 237
- Engines: LYCOMING AEIO-360-A1C 200 horsepower reciprocating
- Damage: Destroyed
- Flight: Personal, Part 91
- Registered owner: Tom D. Jones
- Airworthiness certificate: Standard, Aerobatic
- Last inspection: Annual, September 16, 1982
- Airport: 00K7, Haskell

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 39; commercial; airplane ratings: single-engine land; medical: class 2, valid medical--no waivers/lim.; seat: front; flight hours: 2,205 total, 290 in this make and model

## Weather

- Conditions: Visual (VMC), Day
- Wind: 180° at 15 knots
- Visibility: 15 statute miles
- Lowest ceiling: none
- Temperature: 90 °F
- Altimeter: 29.00 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 19830918050339A](https://openairdocs.org/incident/19830918050339A), Sep 18, 1983: Amtrpt PITTSSPECS1, Haskell, OK, Destroyed. Propeller left the aircraft during a snap roll. Crashed into a hangar. Prop crankshaft flange broke from fatigue.

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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