MIA99LA025

NTSB accident investigation · Ercoupe 415-C · Hartselle, AL · October 31, 1998

Accident · Serious injuriesLimited investigationFinal report
Date
October 31, 1998, 13:30 local (19:30 UTC)
Place
Hartselle, AL
Injuries
1 serious
Damage
Substantial damage
Phase of flight
Approach
Aircraft
N99924Ercoupe 415-C
Weather
Visual (VMC) · Day
Status
Completed · report August 3, 1999
Report
Approved by Office Director
FAA report
19981031031179A
Case key
45191

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

Improper modification of the carburetor float by maintenance personnel resulting in the float sticking in the full needle valve open position and failure of the engine due to excessive fuel flow.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

Loss of engine power(total) - mech failure/malfApproach - vfr pattern - downwind
Fuel system,carburetor float - movement restricted
Maintenance,modification - improperOther maintenance personnelCause
Fluid,fuel - excessive flow/output
Forced landingEmergency descent/landing
In flight collision with objectEmergency descent/landing
Object - wire,transmission
In flight collision with terrain/waterDescent - uncontrolled
Terrain condition - ground

Analysis

The engine lost power as the pilot turned onto the downwind leg for landing. As the pilot approached a field for landing, the aircraft collided with a power line and then the ground. Postcrash examination of the engine showed it was operating with an excessive rich fuel mixture. The carburetor float was found stuck in the full needle valve open position due to excessive solder on the float fulcrum contacting the bowl wall. The carburetor had been recently modified by installing a new style needle valve, which also required the addition of weight to the float fulcrum with solder.

Factual narrative

On October 31, 1998, about 1330 central standard time, an Ercoupe 415-C, N99924, registered to an individual, collided with a power line and crashed in a field while making a forced landing following loss of engine power at Hartselle, Alabama, while on a Title 14 CFR Part 91 personal flight. Visual meteorological conditions prevailed at the time and no flight plan was filed. The aircraft received substantial damage and the private-rated pilot received serious injuries. The flight originated from Roundtree Field, Hartselle, Alabama, about 1245.

The pilot stated this was the first flight since extensive repairs and restoration to the aircraft. After takeoff he departed the airport traffic pattern and climbed to 3,500 feet. He performed maneuvers for about 30 minutes and then returned to the airport traffic for takeoffs and landings. After the second landing, he again took off. As he turned onto the downwind leg, the engine quit without warning. A quick attempt to restart the engine was unsuccessful. He selected a landing site for a forced landing and turned toward it. He was unable to maintain sufficient altitude to clear a power line and the aircraft collided with it, causing the aircraft to nose down. The aircraft then impacted a ditch and bounced and landed on the landing gear, from which a normal landing roll was made.

Postcrash examination of the engine was performed by FAA inspectors. The spark plugs were found to have black soot deposits. The exhaust system also had black soot deposits. The engine was started and operated at idle power for a short time before quitting. A higher engine power was not attempted due to a fuel leak from fuel line damage during ground impact.

The Bendix-Stromberg float carburetor was removed from the engine by FAA inspectors and taken to an overhaul facility. The float was found stuck in the full needle valve open position. Excessive solder on the float fulcrum was contacting the edge of the bowl causing it to stick. The carburetor had been modified in accordance with Bendix-Stromberg Service Bulletin 84 which calls for installation of a new style needle valve which in turn calls for adding of solder weight to the float fulcrum. The service bulletin warns that the added weight should not interfere with the movement of the float. (See attached FAA inspector report)

Aircraft

Registration
N99924
Reported as
Ercoupe 415-C
Category
Airplane
Serial number
2547
Airframe hours
1,202
Engine
Continental C75-12, 85 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Registered owner
Melborne D. Thrasher
Airworthiness certificate
Standard, Normal
Last inspection
Annual · October 31, 1998 · 1 hours before
Departed
5M0
Flight plan
Unknown

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
60
Certificate
Private
Airplane ratings
Single-engine land
Instrument ratings
Airplane
Medical
Class 3, Valid Medical--w/ waivers/lim
Seat
Left
Flight hours
609 total · 41 in this make and model · 507 as pilot in command · 10 in the last 90 days · 6 in the last 30 days · 1 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
350° at 7 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
79 °F, dew point 45 °F
Altimeter
30.00 inHg
Observed at
HSV, 20 nm away

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.