WPR21LA350

NTSB accident investigation · Cessna 404 · Sheridan, WY · September 18, 2021

Accident · No injuriesClass 3 · LimitedFinal report
Date
September 18, 2021, 07:50 local (13:50 UTC)
Place
Sheridan, WY · Side of runway
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N5409GCessna 404
Defining event
Landing-flare/touchdown: Medical event
Weather
Visual (VMC) · Day
Status
Completed
Report
Approved by Office Director
Investigation class
Class 3
NTSB office
Western Pacific Region
Parties
FAA FSDO
FAA report
20210918015899A
Case key
103932

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 experiencing an episode of impaired behavior and incapacitation for reasons that could not be determined based on the available information.

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.

Not determinedNot determined › Not determined · Unknown/Not determinedCessna 404: 3 casesAll aircraft: 2,247 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.

Medical eventLanding-flare/touchdownCessna 404: 1 caseAll aircraft: 63 casesDefining event

Analysis

The pilot stated that the flight and landing approach were uneventful. He recalled configuring the airplane for landing by extending the landing gear and flaps then began the landing flare. His next recollection was of being in the airplane at the right side of the runway surrounded by a cloud of dust. He did not have any recollection of how the airplane got there. Examination of the airplane found the landing gear had collapsed; the nose structure was deformed. While the exact cause of the pilot’s behavior change could not be determined from the available evidence, it is likely he was impaired by a medical event during landing and then possibly incapacitated for a short time. A number of possibilities could explain this event, none of which would have left any direct evidence and all of which could have caused a period of unconsciousness or amnesia. Although he was diagnosed with COVID-19 following the accident, symptoms would have been unlikely to suddenly severely impair the pilot and his memory but allow him to fully recover within a few minutes.

Factual narrative

On September 18, 2021, about 0750, a Cessna 404, N5409G, was substantially damaged when it was involved in an accident near Sheridan, Wyoming. The pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 135 scheduled cargo flight. The pilot stated that he loaded the airplane, along with help from ground handlers, and that there were no HAZMAT packages presented during loading. The total weight of cargo was 154 lbs, and it was loaded behind a net in the aft cargo area. He stated that the flight and landing approach were uneventful, and he recalled configuring the airplane for landing by extending the landing gear and flaps. He began the landing flare, but his next recollection was of being in the airplane at the right side of the runway surrounded by a cloud of dust. He did not have any recollection of how the airplane got there. Examination of the airplane revealed that it had departed runway 15 shortly after landing. The landing gear had collapsed, the nose structure was deformed, and the runway surface exhibited a set of gouges that matched the dimensions of the right wheel rim, and two sets of slash marks consistent with propeller strike. The pilot refused emergency medical treatment at the accident scene, and visited his personal physician three days later, complaining of back and neck pain following the accident. During that visit, his vital signs, including his pulse oximetry, were normal. The pilot recounted the accident circumstances to the physician and was concerned about why he couldn’t remember the events. The medical record stated, “He does not believe he lost consciousness but is unclear.” The physical examination was unremarkable. The physician obtained a chest X-ray, which showed patchy infiltrates, and the pilot tested positive for COVID-19 the following day. He had blood tests that were normal and a brain MRI on October 11, 2021, did not reveal any acute findings. The pilot had reported remote surgeries and seasonal allergies to the FAA at his last medical examination without any use of medications. According to personal medical records, in February 2021, he reported having gastroesophageal reflux disease and using omeprazole to treat it.

Aircraft

Registration
N5409G
Reported as
Cessna 404
Category
Airplane
Serial number
404-0028
Built
1977
Airframe hours
27,377
Engines
Cont Motor TSIO-520 SER, 375 horsepower, reciprocatingCont Motor TSIO-520 SER, 375 horsepower, reciprocating
Damage
Substantial damage
Flight
Other work use · Part 135
Operator
Richland Aviation Inc, doing business as Richland Aviation
Registered owner
Richland Aviation Inc
Airworthiness certificate
Standard, Normal
Last inspection
100 hour · August 30, 2021 · 23 hours before
Departed
BIL · Billings, MT
Destination
Same as departure
Flight plan
VFR
Airport
SHR · Sheridan County, runway 15/33, 8,301 × 100 ft, asphalt
Equipment
ADS-B, Auto-pilot

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
Airline transport
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 2, With waivers/limitations
Last flight review
April 20, 2021
Seat
Left
Restraint
3-point
Flight hours
12,859 total · 3,217 in this make and model · 12,742 as pilot in command · 92 in the last 90 days · 40 in the last 30 days · 2 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
Calm
Visibility
10 statute miles
Lowest ceiling
None
Temperature
57 °F, dew point 34 °F
Altimeter
29.92 inHg
Observed at
KSHR, 1 nm away
METAR
METAR KSHR 181353Z AUTO 00000KT 10SM CLR 14/01 A2992 RMK AO2 SLP114 T01440011=

Docket · 3

The files NTSB released with the investigation on March 1, 2023, on NTSB’s docket system: statements, records, photos and specialists’ reports. 2.4 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.