ANC18LA033

NTSB accident investigation · North Wing Uum Sport X2-N · Pahrump, NV · April 25, 2018

Accident · Serious injuriesLimited investigationFinal report
Date
April 25, 2018, 10:15 local (17:15 UTC)
Place
Pahrump, NV
Injuries
1 serious
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N366DNNorth Wing Uum Sport X2-N
Defining event
Landing-landing roll: Loss of control on ground
Weather
Visual (VMC) · Day
Status
Completed · report March 18, 2019
Report
Approved by Office Director
NTSB office
Alaska Regional Office
Parties
FAA
FAA report
20180425004099A
Case key
97110

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 NTSB’s determination of the probable cause, and any contributing factors.

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 · 4

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings.

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

The factual narrative456 words

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.

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident.

Aircraft

Registration
N366DN
Reported as
North Wing Uum Sport X2-N (NO SERIES)
Category
Weight-shift
Serial number
LS7003
Built
2008
Airframe hours
685
Engine
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

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
61
Injuries
Serious
Certificate
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

Docket · 3

The files NTSB released with the investigation on June 19, 2018, on NTSB’s docket system: statements, records, photos and specialists’ reports. 1.6 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.

Other investigations on N366DN · 1

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