Aviation Accident Summaries

Aviation Accident Summary WPR16LA114

Fruitland, UT, USA

Aircraft #1

N50NE

MICHAEL BURTON Calidus

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 Information

HISTORY OF FLIGHTOn 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 was collected 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.

Probable Cause and Findings

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.

 

Source: NTSB Aviation Accident Database

Get all the details on your iPhone or iPad with:

Aviation Accidents App

In-Depth Access to Aviation Accident Reports