WPR16LA114 · Michael Burton Calidus
Michael Burton Calidus · Accident: turbulence encounter en route
From Duchesne Municipal Airport (U69) to U77 · Spanish Fork, UT
Event
- NTSB case
- WPR16LA114
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Michael Burton Calidus
- Aircraft type
- Michael Burton CALIDUS
- Category
- Gyroplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N50NE
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Duchesne Municipal Airport (U69), Duchesne, UTTo U77 · Spanish Fork, UT
- Aircraft age
- About 2 years (built 2014)
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- En route · cruise
- Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Turbulence encounter
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Aircraft › Aircraft oper/perf/capability
- Environmental issues › Conditions/weather/phenomena
- Environmental issues › Physical environment
- Personnel issues › Action/decision
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
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.
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.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR16LA114
- Event ID
- 20160520X02127
- Case number
- WPR16LA114
- Dataset
- full-current
- Source SHA-256
- 5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status, coordinates. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 495ccf008e5ff941808e2db2ace34af302e17b281c51f3b9b42a6ec0d4a4c603; retrieved 2026-09-16T03:24:52.426Z.