# NTSB ATL89LA126: Grumman AA-5B, N28990, Siler City, NC, April 13, 1989

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: April 13, 1989, 05:15 local (09:15 UTC)
- Place: Siler City, NC
- Coordinates: 35.720821, -79.459053 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=35.7208&lon=-79.4591&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report August 22, 1990
- Report: Approved by Office Director
- NTSB case key (mKey): 8013
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ATL89LA126
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/8013/pdf
- Page: https://openairdocs.org/ntsb/ATL89LA126

## Probable cause

IMPROPER ENGINE OVERHAUL PROCEDURES WHICH RESULTED IN THE CATASTROPHIC FAILURE OF THE ENGINE CRANKSHAFT. CONTRIBUTING TO THE ACCIDENT WAS THE LACK OF A SUITABLE FORCED LANDING AREA.

## 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, cruise - normal
  - engine assembly,crankshaft - fractured (cause)
  - maintenance,overhaul,major - improper, other maintenance personnel (cause)
- Forced landing, descent - emergency
  - terrain condition - none suitable (contributing factor)
- In flight collision with terrain/water, landing
  - terrain condition - ravine
  - terrain condition - roadway/highway

## Analysis

WHILE IN CRUISE FLT THE ENGINE QUIT WITH A LOUD CLUNK. A FORCED LANDING WAS ATTEMPTED ON A HIGHWAY. THE ACFT DID NOT MAKE THE ROAD AND IT HIT AN EMBANKMENT. EXAM OF THE ENGINE REVEALED A BROKEN CRANKSHAFT AT THE FILLET BETWEEN THE NUMBER 4 CRANKPIN & THROW. THE NUMBER 4 CONNECTING ROD SHOWED EVIDENCE OF OVERHEATING. CRANKSHAFT END PLAY WAS FOUND TO BE ONE HALF INCH AT THE ACCESSORY END. ENGINE HAD RECEIVED MAJOR OVERHAUL 81 HOURS PRIOR TO THE FAILURE OF THE CRANKSHAFT.

## Aircraft

- Registration: [N28990](https://openairdocs.org/deregistered/N28990-2013-09-20), registration cancelled 2013-09-20, S/N AA5B0925, built 1978 (OpenAirDocs)
- Reported make and model: GRUMMAN AA-5B
- Registry model: [Gulfstream American AA-5B](https://openairdocs.org/model/gulfstream-american-aa-5b) (registry code 3970106) (OpenAirDocs)
- Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: AA5B-0925
- Airframe hours: 2481
- Engines: LYCOMING O-360-A4K 180 horsepower reciprocating
- Damage: Substantial damage
- Flight: Part 135
- Operator: Wra, Inc
- Registered owner: Wra, Inc
- Airworthiness certificate: Standard, Normal; Standard, Utility
- Last inspection: 100 hour, April 12, 1989, 4 hours before
- Departed: CLT, CHARLOTTE, NC
- Destination: RDU, RALEIGH, NC
- Flight plan: IFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 29; airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, invalid medical for flight; seat: left; flight hours: 3,720 total, 360 in this make and model, 2,900 as pilot in command, 180 in the last 90 days, 65 in the last 30 days, 4 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Dawn
- Wind: 230° at 4 knots
- Visibility: 15 statute miles
- Lowest ceiling: none
- Temperature: 37 °F, dew point 27 °F
- Altimeter: 30.00 inHg
- Observed at: GSO, 30 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 19890413007969A](https://openairdocs.org/incident/19890413007969A), Apr 13, 1989: Gulstm AA5B, Siler City, NC, Substantial damage. Engine failed en route at night. Struck a tree and guard rail trying for a hiway. Crankshaft was broken in 3 pieces

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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