# NTSB CHI87LA068: Cessna 172N, N4688D, Madison, IN, January 27, 1987

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: January 26, 1987, 19:45 local (Jan 27, 1987, 00:45 UTC)
- Place: Madison, IN
- Coordinates: 38.750888, -85.379142 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=38.7509&lon=-85.3791&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report July 5, 1988
- Report: Approved by Office Director
- NTSB case key (mKey): 13722
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI87LA068
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/13722/pdf
- Page: https://openairdocs.org/ntsb/CHI87LA068

## 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, takeoff - initial climb
  - engine assembly,crankshaft - failure,partial (cause)
  - procedures/directives - not followed, other maintenance personnel (cause)
  - maintenance,installation - improper, other maintenance personnel (cause)
  - maintenance,modification - improper, other maintenance personnel (cause)
- Forced landing, takeoff - initial climb
  - light condition - dark night
- In flight collision with object, landing
  - object - utility pole
  - object - wire,transmission
- Nose over, landing - roll

## Analysis

AT APRX 2500 MSL, THE ENG STOPPED AND ATTEMPTS TO RESTART IT WERE NOT SUCCESSFUL. THE INSTRUCTOR TOOK CONTROL OF THE ACFT AND ATTEMPTED TO LAND ON THE HIGHWAY, BUT THE ACFT STRUCK POWERLINES AND A TELEPHONE POLE BEFORE NOSING OVER AND COMING TO REST. THE ENG WAS REMOVED FROM THE ACFT AND SUBSEQUENT TEARDOWN REVEALED THAT THE CRANKSHAFT GEAR TEETH WERE SHEARED. APRX 140 HRS PRIOR TO THE ACCIDENT, A REPAIR STATION HAD RE-NITRIDED THE CRANKSHAFT FOLLOWING RE-GRINDING OPERATIONS, HOWEVER, THE PRESSED ON TYPE GEAR WAS NOT REMOVED, AS REQUIRED, PRIOR TO RE-NITRIDING. SPECIFICATIONS STATE THAT THE GEAR SHOULD HAVE A MIN ROCKWELL HARDNESS OF 30N-77 AND THAT ANY TEMP IN EXCESS OF 300 DEGREES F WOULD AFFECT THE HARDNESS. WHEN TESTED, THE GEAR EXHIBITED A ROCKWELL HARDNESS OF 30N-39. THE TEMP REQUIRED FOR NITRIDING IS IN EXCESS OF 985 DEGREES F.

## Aircraft

- Registration: [N4688D](https://openairdocs.org/deregistered/N4688D-1989-09-29), registration cancelled 1989-09-29, S/N 17272331 (OpenAirDocs)
- Reported make and model: CESSNA 172N
- Registry model: [Cessna 172N](https://openairdocs.org/model/cessna-172n) (registry code 2072434) (OpenAirDocs)
- Category: Airplane
- Serial number: 17272331
- Airframe hours: 1537
- Engines: LYCOMING O-320-H2AD 160 horsepower reciprocating
- Damage: Substantial damage
- Flight: Instructional, Part 91
- Operator: H.F.G., Inc.
- Registered owner: Norman J. Carroll
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, March 20, 1986, 42 hours before
- Departed: IMS, MADISON, IN
- Airport: IM5, Madison Municipal

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 53; flight instructor, airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: right; flight hours: 17,260 total, 105 in this make and model, 15,559 as pilot in command, 200 in the last 90 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Night/dark
- Wind: 350° at 6 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 19 °F, dew point 10 °F
- Altimeter: 30.00 inHg
- Observed at: LOU, 38 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 19870126001019A](https://openairdocs.org/incident/19870126001019A), Jan 26, 1987: Cessna 172N, Madison, IN, Substantial damage. The engine failed. The aircraft hit wires on landing. The crankshaft gear teeth sheared from improper nitriding.

## Other investigations on N4688D (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 MIA85LA262](https://openairdocs.org/ntsb/MIA85LA262), Sep 24, 1985: Cessna 172N (N4688D), Hollywood, FL, 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.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.