CHI94DEP01

NTSB accident investigation · Krotje Kolb Mark III · Oshkosh, WI · November 28, 1993

Accident · No injuriesFinal report
Date
November 28, 1993, 12:46 local (18:46 UTC)
Place
Oshkosh, WI
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Approach
Aircraft
N393PKKrotje Kolb Mark III
Weather
Visual (VMC) · Day
Status
Completed · report September 7, 1994
Report
Approved by Office Director
FAA report
19931128044619A
Case key
9344

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

The lack of carburetor heat for the engine. A factor related to the accident was: the weather condition, which was favorable for formation of carburetor ice.

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) - nonmechanicalApproach - vfr pattern - base leg/base to final
Weather condition - carburetor icing conditionsFactor
Carburetor heat control - not installedCause
Carburetor heat - not possible
Forced landingDescent - emergency
In flight collision with objectLanding
Object - wire,staticFactor
In flight collision with terrain/waterDescent - uncontrolled

Analysis

The engine sustained a loss of power, while the airplane was in the pattern for landing. The pilot was unable to reach the runway of intended landing and made a forced landing in a field. While maneuvering to land, the airplane struck a suspended wire and impacted the terrain. The amateur built airplane was not equipped with a provision for eliminating carburetor icing. The temperature at the time of the accident was 28 degrees, and the dewpoint was 18 degrees. These conditions were condusive to the formation of carburetor ice.

Factual narrative

History of flight

On November 29, 1993, at 1246 CST, an amateur built Kolb Mark III, N393PK, registered to Peter R. Krotje, executed a forced landing in a field due to engine failure, while on right base leg to runway 31 at Wittman Regional Airport, Oshkosh, Wisconsin. The flight was conducted under 14 CFR 91 and was a local personal flight. Visual meteorological conditions prevailed at the time and no flight plan was filed. The aircraft was substantially damaged and the owner, private pilot, Peter R. Krotje, was not injured. The flight originated at Oshkosh, Wisconsin on November 28, 1993, at 1130 CST.

Damage to aircraft

The aircraft received substantial damage upon impact with the terrain, shearing of the right landing gear, bending the fuselage and left landing gear, and tearing a hole in the nose cone.

Aircraft information

The aircraft was home-built and certified as experimental. In as much as the aircraft was experimental, no requirement existed for the use of approved parts, systems, or hardware. The aircraft was not equipped with a system to eliminate carburetor ice and at the time was utilizing automotive fuel.

Test and research

FAA Airworthiness Inspector, Karen E. Belnay, of the Milwaukee, Wisconsin, Flight Standards District Office, tested the Rotax engine. The engine was started, tested, and ran normally.

Additional data

The pilot stated that when he reduced power for landing the engine quit and could not be restarted. He said he was unable to glide to the airport for landing due to his position on right base and the effect of the wind. The pilot stated he did not see a powerline in enough time to avoid contact with it and that said contact slowed him so much that he could not adequately control the impact during landing in the field.

The outside air temperature at the time of the accident was 28 degrees Fahrenheit with a dew point of 18 degrees Fahrenheit. According to icing probability charts, these conditions are conducive to the formation of carburetor ice.

Aircraft

Registration
N393PK
Reported as
Krotje Kolb Mark III (KOLB MARK)
Category
Airplane, amateur-built
Serial number
M3-122
Airframe hours
16
Engine
Rotax 582LC, 65 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Operator
Peter R. Krotje
Registered owner
Peter R. Krotje
Airworthiness certificate
Special, Experimental (Special)
Last inspection
Continuous airworthiness · October 22, 1993 · 16 hours before
Departed
OSH
Destination
OSH
Airport
OSH · Wittman Regional

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
45
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, Unknown
Seat
Left
Flight hours
120 total · 14 in this make and model · 72 as pilot in command · 14 in the last 90 days · 12 in the last 30 days · 1 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
270° at 11 knots
Visibility
15 statute miles
Lowest ceiling
None
Temperature
28 °F, dew point 18 °F
Altimeter
29.00 inHg
Observed at
OSH, 1 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.