ERA21LA188

NTSB accident investigation · Cessna A188 · Dover, NC · April 15, 2021

Accident · No injuriesClass 3 · LimitedFinal report
Date
April 15, 2021, 16:05 local (20:05 UTC)
Place
Dover, NC
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Initial climb
Aircraft
N731TBCessna A188
Defining event
Initial climb: Loss of engine power (total)
Weather
Visual (VMC) · Day
Status
Completed
Report
Approved by Office Director
Investigation class
Class 3
NTSB office
Eastern Region Aviation
Parties
FAA/FSDO
FAA report
20210415006069A
Case key
102935

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

On this page

Probable cause

A total loss of engine power due to a shift of a crankshaft main bearing, which resulted in a lack of lubrication and subsequent overheating and failure of the engine crankshaft. Contributing to the accident was the hard touchdown during the forced landing.

Findings · 2

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Use of equip/info: aircraft controlPersonnel issues › Task performance · PilotCessna A188B: 14 casesAll aircraft: 9,295 casesProbable cause

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

The pilot departed to familiarize himself with the airplane and to practice maneuvers. A few minutes after takeoff, at an altitude of about 300 ft, he heard a “loud pop,” and the engine lost total power. He looked at the engine gauges and noticed that there was “no fuel flow.” As the propeller windmilled, he unsuccessfully attempted to restart the engine, then elected to perform a forced landing to a nearby corn field. He stated that the landing was “hard.” The airplane sustained substantial damage to the left wing, right horizontal stabilizer, and elevator. Examination of the engine revealed that the crankshaft No. 2 main bearing had spun, smearing metal into the oil ports on the bearing bore and deforming the bore. Numerous fragments of bearing material were found in the oil sump and inside the case adjacent to the Nos. 1 and 2 cylinders. Based on the available information, it is likely that the shift of the No. 2 main bearing resulted in a lack of lubrication and subsequent failure of the engine crankshaft. The reason for the bearing shift was not determined.

Factual narrative

On April 15, 2021, at 1605 eastern daylight time, a Cessna A188B, N731TB, was substantially damaged when it was involved in an accident near Dover, North Carolina. The pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. According to the pilot, he fueled the airplane before the flight at a private airport. The purpose of the accident flight was for the pilot to familiarize himself with the airplane and to practice maneuvers in advance of the spraying season. A few minutes after takeoff, at an altitude of about 300 ft, he heard a “loud pop,” and the engine lost all power. He looked at the engine gauges and noticed that there was “no fuel flow.” As the propeller windmilled, he unsuccessfully attempted to restart the engine, then elected to perform a forced landing to a nearby corn field. He stated that the landing was “hard.” Examination of the airplane at the accident site by a Federal Aviation Administration inspector revealed leading edge damage and compression buckling of the top of the left wing outboard of the wing strut, that extended aft of the wing spar. The left side of the empennage was buckled just forward of the vertical stabilizer. The right horizontal stabilizer was bent upward slightly about 12 inches from its root. The upper surface of the right elevator was buckled forward of the trim tab. When the inspector attempted to rotate the propeller by hand, she heard a “clink” sound, and the propeller would not rotate. A follow-up examination and disassembly of the engine revealed that the No. 2 main bearing had spun, smearing metal into the oil ports on the bearing bore and deforming the bore. Numerous fragments of bearing material were found in the oil sump and inside the case, adjacent to the Nos. 1 and 2 cylinders. The remaining main bearings were well lubricated and were normal in appearance. The crankshaft was fractured between main journal No. 2 and rod journal No. 2. There were visible signatures of heat distress near the fracture surfaces. All connecting rods remained attached to their journals on the crankshaft and they rotated freely. A review of the airplane’s maintenance records revealed that the most recent annual inspection was performed 9 days (11 flight hours) before the accident. The previous annual inspection was performed in September 2019, 73 flight hours before the accident.

Aircraft

Registration
N731TB
Reported as
Cessna A188 (B)
Category
Airplane
Serial number
18803133
Built
1978
Airframe hours
5,280
Engine
Continental IO-550-D26B, 300 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Operator
Eastern Flying Services
Registered owner
Eastern Flying Service Inc
Airworthiness certificate
Special, Restricted (Special)
Last inspection
Annual · April 6, 2021 · 11 hours before
Departed
PVT · Dover, NC
Equipment
Satellite tracking device, Handheld GPS

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
58
Injuries
None
Certificate
Commercial
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 2, Without waivers/limitations
Last flight review
October 12, 2020
Seat
Single
Restraint
5-point
Flight hours
7,857 total · 10 in this make and model · 7,152 as pilot in command · 10 in the last 90 days · 10 in the last 30 days · 0 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
310° at 6 knots
Visibility
10 statute miles
Lowest ceiling
9,000 ft overcast
Temperature
68 °F, dew point 57 °F
Altimeter
29.72 inHg
Observed at
ISO, 13.7 nm away

Docket · 8

The files NTSB released with the investigation on April 19, 2023, on NTSB’s docket system: statements, records, photos and specialists’ reports. 95.9 MB in all.

FAA reports on this event · 1

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