N4484EAeronca 7DC 1998-03-31 NTSB Accident Report

Substantial
None

Aeronca 7DC S/N: 104

Summary

On March 31, 1998, a Aeronca 7DC (N4484E) was involved in an incident near Wright, WY. All 1 person aboard were uninjured. The aircraft sustained substantial damage.

The National Transportation Safety Board determined the probable cause of this incident to be: The pilot's use of unsuitable terrain for takeoff. Factors were snow and rock covered terrain, inadequate aircraft preflight, improper aircraft servicing, and the fuel contaminated by water.

On March 31, 1998, at 1100 mountain standard time, a Aeronca 7DC, N4484E, received substantial damage when it struck rocks during takeoff roll from a field 60 miles south of Gillette, Wyoming. The private pilot and sole occupant was not injured. The flight was a local area flight operating under Title 14 CFR Part 91 and no flight plan was filed. Visual meteorological conditions prevailed.

According to information provided by the pilot via his written report (NTSB Form 6120.1/2) and a telephone interview, after about two hours of flight the aircraft was in cruise at about 100 feet above ground level (agl) when the engine lost all power. The pilot performed a forced landing in a field and drained water from the fuel.

This incident is documented in NTSB report FTW98LA169. AviatorDB cross-references NTSB investigation data with FAA registry records to provide comprehensive safety information for aircraft N4484E.

Accident Details

Date
Tuesday, March 31, 1998
NTSB Number
FTW98LA169
Location
WRIGHT, WY
Event ID
20001211X09685
Coordinates
43.749774, -105.490684
Aircraft Damage
Substantial
Highest Injury
None
Fatalities
0
Serious Injuries
0
Minor Injuries
0
Uninjured
1
Total Aboard
1

Probable Cause and Findings

The pilot's use of unsuitable terrain for takeoff. Factors were snow and rock covered terrain, inadequate aircraft preflight, improper aircraft servicing, and the fuel contaminated by water.

Aircraft Information

Registration
Make
AERONCA
Serial Number
104
Engine Type
Turbo-shaft
Year Built
1948
Model / ICAO
7DC A270
Aircraft Type
Fixed Wing Single Engine
No. of Engines
1

Registered Owner (Historical)

Name
JOHNSEN ROY M
Address
22201 109TH DR
Status
Deregistered
City
O BRIEN
State / Zip Code
FL 32071-2613
Country
United States

Analysis

On March 31, 1998, at 1100 mountain standard time, a Aeronca 7DC, N4484E, received substantial damage when it struck rocks during takeoff roll from a field 60 miles south of Gillette, Wyoming. The private pilot and sole occupant was not injured. The flight was a local area flight operating under Title 14 CFR Part 91 and no flight plan was filed. Visual meteorological conditions prevailed.

According to information provided by the pilot via his written report (NTSB Form 6120.1/2) and a telephone interview, after about two hours of flight the aircraft was in cruise at about 100 feet above ground level (agl) when the engine lost all power. The pilot performed a forced landing in a field and drained water from the fuel. After he got the engine restarted, he attempted a takeoff from the field and his main landing gear entered a snow covered area which caused the aircraft to swerve into rocks.

In his telephone interview, the pilot said he normally did not refuel the aircraft until he was preparing for the next flight, which often was at an interval of several days or longer. Thus, his aircraft was sitting with partially filled fuel tanks in an environment where the differential temperature over a 24 hour period varies greatly. According to information provided by several aircraft manufacturers while this investigator was investigating similar accidents where water was found in the fuel, partially filled fuel tanks create a condition in which the fuel tank performs like a "still" and the tank will manufacture water by condensation. The greater the temperature variation, the more water is manufactured.

Data Source

Data provided by the National Transportation Safety Board (NTSB). For more information on this event, visit the NTSB Records Search website. NTSB# FTW98LA169