# NTSB SEA85LYA01: Rockwell S2R, N5511X, Caldwell, ID, August 4, 1985

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Final report
- Date: August 4, 1985, 09:30 local (15:30 UTC)
- Place: Caldwell, ID
- Coordinates: 43.599822, -116.609519 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=43.5998&lon=-116.6095&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 40254
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA85LYA01
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/40254/pdf
- Page: https://openairdocs.org/ntsb/SEA85LYA01

## Sequence of events

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

- Loss of engine power(total) - mech failure/malf, maneuvering - aerial application
  - turbine assembly,turbine wheel - disintegrated (cause)
- Forced landing, descent - emergency
- In flight collision with terrain/water, landing - flare/touchdown

## Analysis

AN AERO COMMANDER S2R HAD BEEN MODIFIED BY THE INSTALLATION OF AN AIR RESEARCH TPE-331-43A POWER PLANT. DURING AN AERIAL APPLICATION FLIGHT THE PILOT HEARD A LOUD BANG AND EXPERIENCED A LOSS OF POWER. INVESTIGATION REVEALED THE FIRST STAGE TURBINE WHEE, PART #867569-4 HAD DISINTEGRATED.

## Aircraft

- Registration: [N5511X](https://openairdocs.org/aircraft/N5511X), registered now, S/N 1711R, built 1973 (OpenAirDocs)
- Reported make and model: Rockwell S2R
- Registry model: [Aero Commander S2R](https://openairdocs.org/model/aero-commander-s2r) (registry code 0143022) (OpenAirDocs)
- Registry engine: [Pratt & Whitney R1340 series](https://openairdocs.org/engine/pratt-whitney-r1340-series) (registry code 52016, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 1711R
- Airframe hours: 29558
- Engines: AIRESEARCH TPE-331-43A 575 horsepower turbo prop
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Operator: Davison'S Air Svc, Inc
- Registered owner: William F. Hubler
- Airworthiness certificate: Special, Restricted (Special)
- Last inspection: Annual, March 21, 1985, 186 hours before
- Departed: G4U, CALDWELL, ID
- Airport: Unknown

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 37; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; seat: center; flight hours: 3,785 total, 3,735 as pilot in command, 588 in the last 90 days, 8 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 20 statute miles
- Lowest ceiling: none
- Temperature: 68 °F, dew point -0 °F

## 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 19850804036139A](https://openairdocs.org/incident/19850804036139A), Aug 4, 1985: Ayres STCS2, Caldwell, ID, Substantial damage. During descent for dusting run,pilot heard loud bang. Landed in field with damage on rollout. Turbine wheel failed.

## Other investigations on N5511X (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 SEA86LA179](https://openairdocs.org/ntsb/SEA86LA179), Jul 25, 1986: Ayres S2R (N5511X), Nampa, ID, destroyed, 1 fatal

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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