# NTSB ANC18LA033: North Wing Uum Sport X2-N, N366DN, Pahrump, NV, April 25, 2018 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: April 25, 2018, 10:15 local (17:15 UTC) - Place: Pahrump, NV - Coordinates: 36.271945, -115.995277 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=36.2719&lon=-115.9953&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-landing roll: Loss of control on ground](https://openairdocs.org/ntsb-events/230) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed, report March 18, 2019 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - Parties: FAA - NTSB case key (mKey): 97110 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC18LA033 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/97110/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=97110 - Page: https://openairdocs.org/ntsb/ANC18LA033 ## Probable cause The pilot's improper landing flare, which resulted in a fractured engine mount sway bar and subsequent difficulty controlling the airplane, and his inadvertent application of throttle pedal during landing, which resulted in a loss of control. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: descent/approach/glide path](https://openairdocs.org/ntsb-findings/01062040): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [North Wing Uum SPORT X2-N, 1 case](https://openairdocs.org/ntsb-findings/01062040/cases.md?model=060006C), [All aircraft, 809 cases](https://openairdocs.org/ntsb-findings/01062040/cases.md) - [Performance/control parameters: landing flare](https://openairdocs.org/ntsb-findings/01062041): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [North Wing Uum SPORT X2-N, 1 case](https://openairdocs.org/ntsb-findings/01062041/cases.md?model=060006C), [All aircraft, 1,285 cases](https://openairdocs.org/ntsb-findings/01062041/cases.md) - [Performance/control parameters: directional control](https://openairdocs.org/ntsb-findings/01062020): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [North Wing Uum SPORT X2-N, 1 case](https://openairdocs.org/ntsb-findings/01062020/cases.md?model=060006C), [All aircraft, 3,958 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md) - [Action: incorrect action performance](https://openairdocs.org/ntsb-findings/02041015): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [North Wing Uum SPORT X2-N, 1 case](https://openairdocs.org/ntsb-findings/02041015/cases.md?model=060006C), [All aircraft, 1,386 cases](https://openairdocs.org/ntsb-findings/02041015/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing: Hard landing](https://openairdocs.org/ntsb-events/092); cases with it: [North Wing Uum SPORT X2-N, 1 case](https://openairdocs.org/ntsb-events/092/sequence.md?model=060006C), [All aircraft, 2,102 cases](https://openairdocs.org/ntsb-events/092/sequence.md) - [Landing-landing roll: Loss of control on ground](https://openairdocs.org/ntsb-events/230) (defining event); cases with it: [North Wing Uum SPORT X2-N, 1 case](https://openairdocs.org/ntsb-events/230/sequence.md?model=060006C), [All aircraft, 4,585 cases](https://openairdocs.org/ntsb-events/230/sequence.md) ## Analysis The sport pilot of the weight-shift control airplane reported that, during landing, the airplane touched down hard, fracturing the engine mount sway bars; the airplane subsequently bounced back into the air. In an attempt to prevent a stall, the pilot elected to go around. As he gained altitude, he realized that the airplane was difficult to control. A witness reported that the airplane made four subsequent landing attempts without touching down. On the fifth approach, the airplane appeared to land hard, bounce, and touch down again before departing the runway. The pilot reported that, upon touchdown, he felt the airplane suddenly accelerate before it began to cartwheel and departed the left side of the runway where it came to rest inverted. Postaccident examination revealed no mechanical malfunctions or anomalies that would have precluded normal operation. The engine throttle was controlled via a foot pedal, and it is likely that the pilot inadvertently depressed the pedal during the landing sequence, which resulted in the acceleration he experienced after touchdown and contributed to the loss of control. ## Factual narrative On April 25, 2018, about 1015 Pacific daylight time, a North Wing UUM Inc Sport X2-N, weight-shift control, special light sport airplane, N366DN, sustained substantial damage following a loss of control during landing at Calvada Meadows Airport (K74P), Pahrump, Nevada. The airplane was registered to a private individual and operated by the pilot as a 14 Code of Federal Regulations (CFR) Part 91 visual flight rules flight when the accident occurred. The sport pilot sustained serious injuries. Visual meteorological conditions prevailed, and no flight plan had been filed. The flight departed K74P for a local flight in the traffic pattern. According to a witness, during a previous landing attempt, the airplane descended toward the runway at a steep angle and failed to flare prior to touching down hard. Following the ground contact, he heard the engine advance and the airplane went around while attempting to gain control of the airplane. The pilot then made four subsequent approaches to the runway, without touching down. On the fifth approach, the airplane appeared to overshoot the runway and then landed hard, bouncing about 30-50ft before touching down again and departing the left side of the runway, coming to rest inverted. The pilot stated on NTSB Accident/Incident Reporting Form 6120.1, that on the landing attempt immediately preceding the accident, he hit hard on the runway and became airborne again. He increased the throttle to gain altitude to go around and re-attempt the landing. As he gained altitude, he realized the airplane was difficult to control and when he made a left turn to enter a downwind leg of the traffic pattern "the aircraft went into a violent left turn." After several more landing attempts, the pilot was getting physically fatigued from fighting to maintain control and decided to make a full-stop landing. After touching down on the runway, he felt the airplane accelerate before it began to cartwheel and departed the left side of the runway. The airplane was designed in such a way that the throttle is controlled by the pilot through the use of a foot pedal. A post-accident examination by Federal Aviation Administration (FAA) inspectors, revealed substantial damage to the wing and a broken engine mount sway bar. Upon further examination it was discovered that the brakes had been removed and the brake lines were capped. No mechanical malfunction or anomaly was discovered that could have led to the sudden acceleration reported by the pilot. The closest official weather observation station to the accident site was McCarran International Airport (KLAS), Las Vegas, Nevada. At 0956, a METAR was reporting, in part, wind 070° at 5 knots; visibility 10 statute miles; few clouds at 25,000ft; temperature 79° F; dew point 25° F; and altimeter 30.07 inches of mercury. ## Aircraft - Registration: [N366DN](https://openairdocs.org/aircraft/N366DN), registered now, S/N LS7003, built 2008 (OpenAirDocs) - Reported make and model: NORTH WING UUM INC SPORT X2-N (NO SERIES) - Registry model: [North Wing Uum SPORT X2-N](https://openairdocs.org/model/north-wing-uum-sport-x2-n) (registry code 060006C) (OpenAirDocs) - Registry engine: [Rotax 582SER](https://openairdocs.org/engine/rotax-582ser) (registry code 55556, 2 cycle) (OpenAirDocs) - Category: Weight-shift - Serial number: LS7003 - Year built: 2008 - Airframe hours: 685 - Engines: Rotax 582 65 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Special light-sport (Special) - Last inspection: Annual, January 27, 2018, 13 hours before - Departed: 74P, Pahrump, NV - Destination: 74P, Pahrump, NV - Airport: 74P, Calvada Meadows, runway 15, 4,081 × 48 ft, asphalt - Equipment: Unknown ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 61; injuries: serious; sport pilot; medical: sport pilot; last flight review April 24, 2018; seat: single; restraint: lap only; flight hours: 30 total, 30 in this make and model, 14 as pilot in command, 2 in the last 90 days, 2 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 70° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 79 °F, dew point 25 °F - Altimeter: 30.06 inHg - Observed at: KLAS, 42 nm away ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20180425004099A](https://openairdocs.org/incident/20180425004099A), Apr 25, 2018: North Wing Uum Inc SPORT X2-N, Pahrump, NV, Substantial damage. On April 25, 2018, at 1843 UTC, a 2008 North Wing Uum Inc sport X2-N, light sport weight shift aircraft, impacted the terrain while attempting to land at… ## Other investigations on N366DN (1) From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [NTSB GAA17CA250](https://openairdocs.org/ntsb/GAA17CA250), Apr 30, 2017: North Wing Uum Sport X2-N (N366DN), Boulder City, NV, substantial damage. Probable cause: The student pilot’s exceedance of the weight-shift-control aircraft’s critical angle of attack and the flight instructor’s delayed remedial action and failure to maintain the proper airspeed after… ## Docket (3 files) The files NTSB released with the investigation on June 19, 2018, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=97110. 1.6 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 719 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40464155&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Witness Statement (item 2, .PDF, 206 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40464156&FileExtension=.PDF&FileName=Witness%20Statement-Master.PDF - Photo Array (item 3, .PDF, 3 photos, 629 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40464157&FileExtension=.PDF&FileName=Photo%20Array-Master.PDF From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.