CEN20LA125

NTSB accident investigation · Mitsubishi MU 2B-40 · Chilton, WI · January 29, 2020

Accident · No injuriesClass 3 · LimitedFinal report
Date
January 29, 2020, 09:00 local (15:00 UTC)
Place
Chilton, WI
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N425GZMitsubishi MU 2B-40
Defining event
Landing: Loss of control on ground
Weather
Visual (VMC) · Day
Status
Completed
Report
Approved by Office Director
Investigation class
Class 3
NTSB office
Central Region
Parties
Honeywell Aerospace, Hartzell Propeller Inc, Flight Standards District Office, Mitsubishi Heavy Industries America, Inc.
FAA report
20200129000939A
Case key
101087

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

The pilot's decision to land on the turf runway with insufficient landing performance and his subsequent loss of control during the landing roll.

Findings · 5

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.

Runway/land/takeoff/taxi surfaceEnvironmental issues › Physical environment · Decision related to conditionMitsubishi MU-2B-40: 1 caseAll aircraft: 253 casesProbable cause
Use of equip/info: aircraft controlPersonnel issues › Task performance · PilotMitsubishi MU-2B-40: 2 casesAll aircraft: 9,295 casesProbable cause
Aircraft capability: landing distanceAircraft › Aircraft oper/perf/capability · Capability exceededMitsubishi MU-2B-40: 1 caseAll aircraft: 68 casesProbable cause
Performance/control parametersAircraft › Aircraft oper/perf/capability · Not attained/maintainedMitsubishi MU-2B-40: 1 caseAll aircraft: 1,269 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 was landing the turbine-powered airplane on a 2,500-ft-long frozen, turf runway. The pilot reported to the manufacturer that, during the landing roll, the airplane yawed left and the right wing contacted the ground, resulting in substantial damage. Examination of the airplane did not reveal any anomalies that would have resulted in a directional control issue. According to the pilot operating handbook, the airplane’s landing distance over a 50-ft for a dry, hard surface runway was about 2,500 ft. The manufacturer estimated that this distance for a wet or turf runway were about 4,250 ft. The pilot did not respond to requests for information regarding his flight planning or estimated landing distance. The pilot's decision to land on a runway that provided an inadequate distance likely resulted in an inability to maintain control of the airplane during the landing roll.

Factual narrative

The flight manual contained landing distance information for a dry, hard surface runway. Landing distance information for a turf runway was not available to the pilot. Investigators calculated airplane landing performance based on ambient temperature, calm wind, zero runway slope, an airplane weight of 500 lbs above empty weight, flaps at 20°, and no use of reverse thrust. Estimated landing distance over a 50 ft obstacle and ground roll were 2,500 and 1,500 ft, respectively. The airplane manufacturer estimated the landing distance over a 50 ft obstacle and ground roll for a turf (or wet) runway to be about 4,250 and 3,250 ft, respectively. The pilot did not respond to requests for additional information, such as expected landing distance, runway braking condition, touchdown location, actions taken after touchdown, and where the airplane departed the runway surface. According to the pilot, the turf runway was 2,500 ft x 85 ft; publicly available information indicated the turf runway was 1,000 x 60 ft. On January 29, 2020, about 0900 central standard time, a Mitsubishi MU-2B-40 airplane, N425GZ, was substantially damaged when it was involved in an accident at Flying Feathers Airport (11Y), Chilton, Wisconsin. The pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations (CFR) Part 91 personal flight. The National Transportation Safety Board (NTSB) was informed of the accident on March 12, 2020, by the airframe manufacturer; it was not reported to the NTSB by the pilot. The pilot stated that while landing at his private turf airstrip, the airplane yawed left and the right wing was substantially damaged when it contacted the ground. On December 14, 2019, the pilot completed an initial MU-2 training course, which included 14.9 flight hours and 20 hours of ground training as required 14 CFR Part 91 Subpart N. An examination of the airplane, which included engine rigging, propellers, and flight control continuity, did not reveal an anomaly that would have resulted in a directional control issue.

Aircraft

Registration
N425GZ
Reported as
Mitsubishi MU 2B-40
Category
Airplane
Serial number
425 S.A.
Built
1980
Airframe hours
4,723
Engines
Honeywell TPE-33110511M, 940 horsepower, turbo propHoneywell TPE-33110511M, 940 horsepower, turbo prop
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Standard, Normal
Last inspection
100 hour · August 9, 2019 · 49 hours before
Departed
8D1 · New Holstein, WI
Destination
11Y · Chilton, WI
Airport
11Y · Flying Feathers, runway 18, 2,500 × 85 ft, grass/turf

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
48
Injuries
None
Certificate
Airline transport
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 1, With waivers/limitations
Last flight review
December 14, 2019
Seat
Left
Restraint
4-point
Flight hours
21,000 total · 93 in this make and model · 53 in the last 90 days · 27 in the last 30 days · 0 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
Calm
Visibility
10 statute miles
Lowest ceiling
2,800 ft overcast
Temperature
25 °F, dew point 18 °F
Altimeter
30.20 inHg
Observed at
KOSH, 16 nm away

Docket · 7

The files NTSB released with the investigation on November 19, 2020, on NTSB’s docket system: statements, records, photos and specialists’ reports. 6.2 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.