# NTSB DEN85LA093: Cessna 421C, N98487, Butte, MT, February 28, 1985

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: February 28, 1985, 14:00 local (21:00 UTC)
- Place: Butte, MT
- Coordinates: 46.000537, -112.440757 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=46.0005&lon=-112.4408&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 16648
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN85LA093
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/16648/pdf
- Page: https://openairdocs.org/ntsb/DEN85LA093

## Sequence of events

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

- Fire, cruise - normal
  - hydraulic system,fitting - failure,total (cause)
  - fluid,hydraulic - leak

## Analysis

WHILE IN LEVEL FLT THE PLT NOTICED A PUFF OF SMOKE EMIT FROM THE LEFT ENGINE, FOLLOWED BY THE APPEARANCE OF HYDRAULIC FLUID AND THE ILLUMINATION OF THE LEFT AND RIGHT HYDRAULIC FLOW LIGHTS. THE PLT LOWERED THE LANDING GEAR DURING THE APCH, HOWEVER, THE NOSE GEAR DID NOT EXTEND. FLAMES WERE THEN NOTICED BURNING THROUGH THE TOP OF THE LEFT ENGINE COWLING. THE PLT SECURED THE ENGINE, USED THE EMERGENCY EXTENSION FOR THE NOSE GEAR AND LANDED THE ACFT. INVESTIGATION REVEALED THE FIRE STARTED FROM HYDRAULIC FLUID WHICH SPRAYED FROM A BROKEN HYDRAULIC LINE ONTO THE SUPERCHARGER. A SWIVEL HOSE ALUMINUM FITTING, P/N AE70101JZ174, ON THE HYDRAULIC LINE FAILED FOR UNDETERMINED REASONS.

## Aircraft

- Registration: N98487 (not matched to a registry record)
- Reported make and model: CESSNA 421C
- Category: Airplane
- Serial number: 421C-0065
- Airframe hours: 260
- Engines: CONTINENTAL TSIO-520L 375 horsepower reciprocating
- Damage: Substantial damage
- Fire: In-Flight
- Flight: Ferry, Part 91
- Registered owner: C & M Aviation
- Airworthiness certificate: Standard, Normal
- Last inspection: 100 hour, October 15, 1984, 79 hours before
- Departed: OAKLAND, CA
- Flight plan: IFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 38; airline transport, flight instructor; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 7,511 total, 40 in this make and model, 7,161 as pilot in command, 109 in the last 90 days, 3 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 320° at 10 knots
- Visibility: 30 statute miles
- Lowest ceiling: none
- Temperature: 50 °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 19850228030089A](https://openairdocs.org/incident/19850228030089A), Feb 28, 1985: Cessna 421C, Butte, MT, Substantial damage. Hydraulic fluid leak and fire warning in flight. Blew nose gear down, shutdown engine, landed at destination.

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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