# NTSB CHI82DA185: Hughes 369D, N8348F, Fairbury, IL, May 26, 1982

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Final report
- Date: May 26, 1982, 15:00 local (20:00 UTC)
- Place: Fairbury, IL
- Coordinates: 40.739612, -88.509132 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=40.7396&lon=-88.5091&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 3 uninjured
- Status: Completed, report May 26, 1983
- Report: Approved by Office Director
- NTSB case key (mKey): 70654
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI82DA185
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/70654/pdf
- Page: https://openairdocs.org/ntsb/CHI82DA185

## Sequence of events

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

- Airframe/component/system failure/malfunction, cruise - normal
  - turboshaft engine,free turbine governor - corroded (cause)
  - turboshaft engine,free turbine governor - blocked(total) (cause)
  - maintenance - inadequate, other maintenance personnel (cause)
  - turboshaft engine - overspeed
- Hard landing, landing - flare/touchdown
  - precautionary landing - initiated, pilot in command
  - autorotation - performed, pilot in command
  - terrain condition - wet (contributing factor)
  - terrain condition - soft (contributing factor)

## Analysis

DURING FLIGHT, THE N2 AND NR SUDDENLY ACCELERATED TO 110 PERCENT. THE PILOT EVENTUALLY SHUT DOWN THE ENGINE AND MADE AN AUTOROTATION. AN OPEN FIELD WAS SELECTED FOR A LANDING SITE; HOWEVER, IT WAS MUDDY WITH STANDING WATER. THE PILOT DECIDED ON A FULL STOP LANDING RATHER THAN A SLIDE-ON LANDING TO AVOID A NOSE OVER. DURING TOUCHDOWN, THE MAIN ROTOR BLADES FLEXED DOWNWARD AND SEVERED THE TAIL BOOM. AN INVESTIGATION REVEALED THERE WAS SAND AND ALUMINUM HYDROXIDE CORROSION IN THE TURBINE GOVERNOR, PN 2524706-3. ALSO, SOME CORROSION AND FOREIGN MATERIAL WAS FOUND IN THE FUEL CONTROLUNIT, PN 2524644-1. BOTH UNITS HAD 2.5 HRS OF OPERATION SINCE THEY WERE INSTALLED ON THIS AIRCRAFT. AN INSPECTION OF THEGOVERNOR SHOWED THAT THE PG CHANNEL IN THE DRIVE BODY WAS COMPLETELY BLOCKED. THIS BLOCKAGE WOULD HAVE RESULTED IN AN ENGINE OVERSPEED OF UP TO 112 PERCENT. THE GOVERNOR HAD BEEN SALVAGED FROM A HELICOPTER THAT HAD BEEN IN AN ACCIDENT IN BRAZIL. THE CORROSION WAS INDICATIVE OF LONG TERM EXPOSURE TO THE ENVIRONMENT.

## Aircraft

- Registration: [N8348F](https://openairdocs.org/aircraft/N8348F), registered now, S/N 1260051D (OpenAirDocs)
- Reported make and model: HUGHES 369D
- Registry model: [Hughes Helicopters HUGHES 369D](https://openairdocs.org/model/hughes-helicopters-hughes-369d) (registry code 4470706) (OpenAirDocs)
- Category: Helicopter
- Serial number: 1260051D
- Airframe hours: 1312
- Engines: ALLISON 250-C20B 375 horsepower turbo shaft
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Norman P. Rittenhouse
- Registered owner: Norman P. Rittenhouse
- Departed: FAIRBURY, IL
- Destination: FAIRBURY, IL

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 41; commercial, flight instructor; medical: class 2, valid medical--no waivers/lim.; flight hours: 4,813 total, 806 in this make and model, 4,725 as pilot in command, 17 in the last 90 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: variable at 5 knots
- Visibility: 15 statute miles
- Temperature: 149 °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 19820526019249A](https://openairdocs.org/incident/19820526019249A), May 26, 1982: Hughes 369D, Fairbury, IL, Substantial damage. Engine 2 and nr showed overspeed condition. Tail boom severed on landing. Turbine governor fouled with corrosion.

## Other investigations on N8348F (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 ANC81DAD05](https://openairdocs.org/ntsb/ANC81DAD05), Aug 15, 1981: Hughes 369D (N8348F), Swan Lake, AK, destroyed

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.