N7551C

Substantial
None

Forney F-1 S/N: 5668

Accident Details

Date
Sunday, August 25, 1996
NTSB Number
SEA96LA203
Location
BOZEMAN, MT
Event ID
20001208X06638
Coordinates
45.770072, -110.929512
Aircraft Damage
Substantial
Highest Injury
None
Fatalities
0
Serious Injuries
0
Minor Injuries
0
Uninjured
2
Total Aboard
2

Probable Cause and Findings

the pilot's failure to adequately service the engine with oil before flight, which resulted in a loss of oil pressure and a subsequent forced landing. The high vegetation and embankment at the forced landing site were related factors.

Aircraft Information

Registration
Make
FORNEY
Serial Number
5668
Engine Type
Reciprocating
Model / ICAO
F-1
Aircraft Type
Fixed Wing Single Engine
No. of Engines
1
Seats
2
FAA Model
F-1

Registered Owner (Current)

Name
STRADLEY ROGER I
Address
5835 SPAULDING BRIDGE RD
City
BELGRADE
State / Zip Code
MT 59714-8113
Country
United States

Analysis

On August 25, 1996, approximately 1520 mountain daylight time, a Forney F-1, N7551C, sustained substantial damage during a forced landing on a road near Bozeman, Montana. The pilot and his passenger were uninjured. No flight plan was filed for the flight, which was conducted in visual meteorological conditions and had originated in Townsend, Montana about 1500. There was no report of the ELT actuating.

The pilot stated that he had departed Bozeman about 1310 with 2.6 quarts of oil showing on the dip stick. About 1.5 hours later, he landed at Townsend to check the oil level (the pilot stated that the airplane "throws a little oil"). Oil level at that time was 2.4 quarts. The pilot took off for a return flight to Bozeman. He stated that oil pressure remained normal during climb; about 15 minutes into the flight while cruising, the oil pressure dropped about 2 psi to 33 psi.

The pilot stated that about 20 minutes after takeoff from Townsend, he experienced a complete oil pressure loss. He said he shut the engine down and picked out an abandoned railroad bed, which is used as a farm road, as a forced landing site. He said that touchdown was normal, and the airplane rolled several hundred feet , when sagebrush on the right side dragged on the airplane, forcing it off the road into a ditch on the right side, where substantial damage was caused as the airplane rolled down the embankment.

The pilot said he checked oil level after landing, which he said was about 2.3 quarts; when the wreckage was recovered, the dip stick recorded 1.5 quarts. He believed normal oil capacity on the airplane to be 4.25 quarts. FAA Type Certificate Data Sheets \note that total oil capacity is 5 quarts maximum, and 2 quarts minimum operating supply on this installation. The pilot noted that on his previous flights in the airplane, he had considered the minimum oil level to be 3 quarts for flight; for some reason on this flight, he had thought he should burn the oil down to 2 quarts before adding a quart.

Data Source

Data provided by the National Transportation Safety Board (NTSB). For more information on this event, visit the NTSB Records Search website. NTSB# SEA96LA203