WPR16LA114

NTSB accident investigation · Michael Burton Calidus · Fruitland, UT · May 20, 2016

Accident · Serious injuriesLimited investigationFinal report
Date
May 20, 2016, 11:00 local (17:00 UTC)
Place
Fruitland, UT
Injuries
2 serious
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N50NEMichael Burton Calidus
Defining event
Enroute-cruise: Turbulence encounter
Weather
Visual (VMC) · Day
Status
Completed · report May 1, 2017
Report
Approved by Office Director
NTSB office
Western Pacific Region
Parties
Federal Aviation Administration FSDO
FAA report
20160520024549A
Case key
93217

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 pilot's improper judgment in conducting a flight in a gyroplane over mountainous terrain near its demonstrated maximum operating altitude and his subsequent failure to maintain adequate clearance with terrain during cruise flight in turbulent weather conditions.

Findings · 6

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.

Performance/control parameters: altitudeAircraft › Aircraft oper/perf/capability · Not attained/maintainedMichael Burton CALIDUS: 1 caseAll aircraft: 1,310 casesProbable cause
Aircraft capability: climb capabilityAircraft › Aircraft oper/perf/capability · Attain/maintain not possibleMichael Burton CALIDUS: 1 caseAll aircraft: 183 casesProbable cause
Terrain: mountainous/hilly terrainEnvironmental issues › Physical environment · Effect on operationMichael Burton CALIDUS: 1 caseAll aircraft: 329 casesProbable cause
Turbulence: terrain induced turbulenceEnvironmental issues › Conditions/weather/phenomena · Effect on operationMichael Burton CALIDUS: 1 caseAll aircraft: 70 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

After fueling the gyroplane, the private pilot and passenger embarked on a cross-country flight over rugged and mountainous terrain. The pilot reported that, as the gyroplane approached a ridge, about 200 ft above its peak, it encountered strong downdrafts and then descended into a box canyon. Unable to climb the gyroplane to clear terrain, the pilot guided it over a river at the base of the canyon until he could see a landing spot on the shore. As he approached the site and initiated the landing flare, the right wheel struck a boulder, and the gyroplane rolled over and then came to rest in the river. The canyon in which the gyroplane came to rest was at an elevation of about 7,300 ft mean sea level (msl), and the canyon walls rose about 1,000 ft above the accident site to the north and south. The gyroplane's demonstrated maximum operating altitude was 10,000 ft, and the pilot's intended flight route would have required clearing mountain peaks that were at an elevation of 8,200 ft msl. The pilot reported that there were no mechanical malfunctions or failures with the gyroplane. Local wind conditions, along with the rugged terrain, likely resulted in mechanical turbulence and strong downdrafts along the flight route, and it is likely that the weather conditions affected the gyroplane's ability to achieve a positive climb rate. Given the weather conditions and the gyroplane's maximum operating altitude of 10,000 ft, the pilot demonstrated improper judgment by attempting such a flight. The pilot stated that he could have avoided the accident if he had approached the mountain ridge at a higher altitude. The accident site was inaccessible to first responders, which resulted in the pilot's blood being drawn about 5 hours following the accident. Toxicological testing revealed strong evidence that he had used marijuana at some point before the accident. Although he had no significant active drug (tetrahydrocannabinol [THC]) in his blood at the time it was drawn, it could not be determined how much THC was in this blood at the time of the accident. Therefore, it could not be determined if impairment due to marijuana use contributed to the pilot's poor decision-making.

Factual narrative

On May 20, 2016, about 1100 mountain daylight time, an experimental amateur-built Michael Burton (AutoGyro GmbH) Calidus, N50NE, collided with mountainous terrain near Fruitland, Utah. The gyroplane was registered to the builder and operated by the pilot under the provisions of 14 Code of Federal Regulations (CFR) Part 91. The private pilot and passenger were seriously injured, and the gyroplane sustained substantial damage. The cross-country personal flight departed Duchesne Municipal Airport, Duchesne, Utah, about 1015, with a planned destination of Spanish Fork Airport-Springville-Woodhouse Field, Spanish Fork, Utah. Visual meteorological conditions prevailed, and no flight plan had been filed. The pilot reported that they departed from Glenwood Springs Municipal Airport, Glenwood Springs, Colorado, earlier that morning and stopped at Duchesne for fuel. They then departed west towards Spanish Fork on a route over the Wasatch Mountain Range. As they approached the last ridge, about 200 ft above its peak, they encountered strong downdrafts and the gyroplane descended 500 ft and into a box canyon. Unable to out-climb the terrain, the pilot guided the gyroplane over a river at the base of the canyon until he could see a landing spot on the shore. As he approached the site and initiated the landing flare, the right wheel struck a boulder and the gyroplane rolled over, coming to rest in the river. A witness, who was fishing in the river, called 911 after climbing to a peak where he was able to acquire cell phone reception. Due to the remoteness of the site, the pilot and passenger were not recovered until later in the afternoon. The gyroplane came to rest within a canyon, at an elevation of about 7,300 ft mean sea level. The canyon walls rose about 1,000 ft above the accident site to the north and south. The projected route of flight would have required clearance over rugged 8,200 ft peaks, about 5 miles north of the 9,420 ft summit of Baldy Mountain. About the time of the accident, a weather observation station located at Carbon County Regional Airport/Buck Davis Field, 37 miles south-southeast of the accident site and at an elevation of 5,957 ft, reported wind from 170 degrees at 20 knots gusting 25 knots. About the same time, at Provo Municipal Airport, 38 miles west at an elevation of 4,497 ft, wind was reported from 130 degrees at 15 knots, gusting to 22 knots. The gyroplanes Pilot Operating Handbook specified a maximum demonstrated operating altitude of 10,000 ft. The pilot reported that the gyroplanes maximum gross weight was 1,256 pounds, and the that the weight at the time of the accident was 1,100 pounds. The pilot stated that the gyroplane did not experience any mechanical malfunctions or failures, and that the accident could have been avoided if he had approached the mountain ridge at a higher altitude. The Federal Aviation Administration Bioaeronautical Research Laboratory performed toxicology tests on a sample of blood that wascollected from the pilot at 1546 on the day of the accident. Results identified 0.0111 ug/ml of tetrahydrocannabinol carboxylic acid (THC-COOH) in his blood. Tetrahydrocannabinol carboxylic acid (THC-COOH) is the primary metabolite of tetrahydrocannabinol (THC), the main psychoactive compound in marijuana. The report did not document the presence of THC. The reporting cutoff for THC was 0.001 ug/ml.

Aircraft

Registration
N50NE
Reported as
Michael Burton Calidus
Category
Gyroplane, amateur-built
Serial number
C00240
Built
2014
Airframe hours
350
Engine
Rotax 914, 115 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Special, Experimental (Special)
Last inspection
Condition · May 20, 2016 · 25 hours before
Departed
U69 · Duchesne, UT
Destination
U77 · Spanish Fork, UT
Equipment
Handheld GPS, Electronic multifunction display

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
57
Injuries
Serious
Certificate
Private
Medical
Class 3, With waivers/limitations
Last flight review
January 25, 2016
Seat
Front
Restraint
4-point
Toxicology
Performed
Flight hours
285 total · 235 in this make and model · 215 as pilot in command · 120 in the last 90 days · 60 in the last 30 days · 6 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
170° at 20 knots, gusting 25
Visibility
10 statute miles
Lowest ceiling
None
Temperature
64 °F, dew point 34 °F
Altimeter
29.81 inHg
Observed at
KPUC, 33 nm away

Docket · 3

The files NTSB released with the investigation on February 16, 2017, on NTSB’s docket system: statements, records, photos and specialists’ reports. 779 KB 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.

Other investigations on N50NE · 1

Matched to the same aircraft by N-number and date.