# NTSB DEN84LA240: Cessna 310Q, Havre, MT, July 27, 1984

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: July 27, 1984, 17:20 local (23:20 UTC)
- Place: Havre, MT
- Coordinates: 48.560192, -109.730323 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=48.5602&lon=-109.7303&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 7 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 16447
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN84LA240
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/16447/pdf
- Page: https://openairdocs.org/ntsb/DEN84LA240

## Sequence of events

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

- Loss of engine power(partial) - mech failure/malf, cruise - normal
  - lubricating system,oil seal - failure,partial (cause)
  - fluid,oil - leak (cause)
  - propeller feathering - performed, pilot in command
- Forced landing, landing
- On ground/water encounter with terrain/water, landing - roll
  - terrain condition - rough/uneven

## Analysis

DURING CRUISE FLIGHT WITH FIVE ADULTS AND TWO INFANTS ON BOARD, THE PILOT NOTED LEFT ENGINE OIL PRESSURE DECREASING AND A VISIBLE OIL LEAK. ENGINE SHUTDOWN AND PROPELLER FEATHER WERE ACCOMPLISHED BUT ALTITUDE COULD NOT BE MAINTAINED. A FORCED LANDING WAS PERFORMED IN AN OPEN FIELD. AN 'O' RING FAILURE WAS FOUND ON THE LEFT ENGINE.

## Aircraft

- Registration: CGONG (not matched to a registry record)
- Reported make and model: CESSNA 310Q
- Category: Airplane
- Serial number: 1048
- Airframe hours: 1158
- Engines: CONTINENTAL IO-470-VO 260 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Harold J. Lewis
- Airworthiness certificate: Standard, Normal
- Last inspection: Unknown, May 30, 1984, 17 hours before
- Departed: PINCHER CREEK
- Destination: MDT, MINOT, SD
- Flight plan: VFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 46; private; airplane ratings: single-engine land, multi-engine land; medical: class 3, valid medical--w/ waivers/lim; seat: left; flight hours: 748 total, 400 in this make and model, 27 in the last 90 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 100° at 15 knots
- Visibility: 25 statute miles
- Lowest ceiling: none
- Temperature: 81 °F

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.