# NTSB MKC83LA166: Schippers BD-4, N412JS, Danbury, IA, July 28, 1983

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: July 28, 1983, 18:15 local (23:15 UTC)
- Place: Danbury, IA
- Coordinates: 42.230979, -95.720634 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=42.2310&lon=-95.7206&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 33451
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MKC83LA166
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/33451/pdf
- Page: https://openairdocs.org/ntsb/MKC83LA166

## Sequence of events

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

- Airframe/component/system failure/malfunction, cruise - normal
  - propeller system/accessories,hub - failure,total (cause)
  - propeller system/accessories,hub - separation (cause)
- Forced landing, landing - flare/touchdown
- Gear collapsed, landing - flare/touchdown
  - terrain condition - rough/uneven (contributing factor)

## Analysis

WHILE EN ROUTE, THE PROPELLER SEPARATED FROM THE HOME BUILT ACFT. SUBSEQUENTLY, THE NOSE GEAR FAILED & THE MAIN GEAR WERE DAMAGED DURING A LANDING ON ROLLING TERRAIN. AN EXAMINATION REVEALED THAT THE MOUNTING BOLTS FOR A PROPELLER SPACER HAD FAILED. THE SPACER HAD BEEN INSTALLED BETWEEN THE ENGINE & THE PROPELLER TO OFFSET A CLEARANCE PROBLEM.

## Aircraft

- Registration: [N412JS](https://openairdocs.org/deregistered/N412JS-2013-04-08), registration cancelled 2013-04-08, S/N 412, built 1978 (OpenAirDocs)
- Reported make and model: SCHIPPERS BD-4
- Registry model: [Schippers BD 4](https://openairdocs.org/model/schippers-bd-4) (registry code 1130480) (OpenAirDocs)
- Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs)
- Category: Airplane, amateur-built
- Serial number: 412
- Airframe hours: 402
- Engines: LYCOMING O-360 180 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: John V. Schippers
- Last inspection: Annual, September 1, 1982
- Departed: ANW, AINSWORTH, NE
- Destination: MIW, MARSHALL TOWN, IA
- Flight plan: VFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 54; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; seat: left; flight hours: 1,600 total, 402 in this make and model, 1,600 as pilot in command, 34 in the last 90 days, 10 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 60° at 11 knots
- Visibility: 6 statute miles
- Lowest ceiling: 5,000 ft broken
- Temperature: 82 °F, dew point 72 °F
- Altimeter: 29.00 inHg
- Observed at: OMA, 65 nm away

## 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 19830728036559A](https://openairdocs.org/incident/19830728036559A), Jul 28, 1983: Amtrbd BEDEBD4, Danbury, IA, Substantial damage. Propeller spacer bolts fractured and propeller came off. Crash occurred during emergency landing.

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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