# NTSB CEN14CA532: Airborne Edge X, N2017A, Willow Springs, MO, September 1, 2014 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Data collection · Final report - Date: September 1, 2014, 06:50 local (11:50 UTC) - Place: Willow Springs, MO - Coordinates: 36.989723, -91.95417 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=36.9897&lon=-91.9542&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing: Windshear or thunderstorm](https://openairdocs.org/ntsb-events/390) - Highest injury: Minor injuries - Injuries: 2 minor - Status: Completed, report April 7, 2015 - Report: Approved by Office Director - NTSB office: Central Region - Parties: Federal Aviation Administration, St. Louis FSDO - NTSB case key (mKey): 90399 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN14CA532 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/90399/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=90399 - Page: https://openairdocs.org/ntsb/CEN14CA532 ## Probable cause The pilot's loss of control after the weight-shift-control aircraft encountered low-level wind shear shortly before touchdown. Also causal to the accident was the pilot's inadequate preflight weather assessment that failed to correctly determine the actual location and speed of the approaching line of thunderstorms. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Wind: windshear](https://openairdocs.org/ntsb-findings/03034020): Environmental issues › Conditions/weather/phenomena · Ability to respond/compensate (probable cause); cases with it: [Airborne EDGE X, 1 case](https://openairdocs.org/ntsb-findings/03034020/cases.md?model=05902J4), [All aircraft, 90 cases](https://openairdocs.org/ntsb-findings/03034020/cases.md) - [Planning/preparation: weather planning](https://openairdocs.org/ntsb-findings/02061020): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Airborne EDGE X, 1 case](https://openairdocs.org/ntsb-findings/02061020/cases.md?model=05902J4), [All aircraft, 156 cases](https://openairdocs.org/ntsb-findings/02061020/cases.md) - [Info processing/decision: identification/recognition](https://openairdocs.org/ntsb-findings/02041510): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Airborne EDGE X, 1 case](https://openairdocs.org/ntsb-findings/02041510/cases.md?model=05902J4), [All aircraft, 559 cases](https://openairdocs.org/ntsb-findings/02041510/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Prior to flight: Preflight or dispatch event](https://openairdocs.org/ntsb-events/030); cases with it: [Airborne EDGE X, 1 case](https://openairdocs.org/ntsb-events/030/sequence.md?model=05902J4), [All aircraft, 355 cases](https://openairdocs.org/ntsb-events/030/sequence.md) - [Landing: Windshear or thunderstorm](https://openairdocs.org/ntsb-events/390) (defining event); cases with it: [Airborne EDGE X, 1 case](https://openairdocs.org/ntsb-events/390/sequence.md?model=05902J4), [All aircraft, 224 cases](https://openairdocs.org/ntsb-events/390/sequence.md) - [Landing: Loss of control in flight](https://openairdocs.org/ntsb-events/240); cases with it: [Airborne EDGE X, 1 case](https://openairdocs.org/ntsb-events/240/sequence.md?model=05902J4), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) - [Landing: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Airborne EDGE X, 1 case](https://openairdocs.org/ntsb-events/470/sequence.md?model=05902J4), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The pilot stated that, about 45 minutes before departure, he obtained the current weather conditions via an internet website and observed a thunderstorm located about 100 miles west of the departure airport. About 20 minutes into the local area flight, he recalled seeing a low cloud bank, with a base of about 1,000 feet above ground level (agl), about 1/4 mile east of the airport. At the same time, he noticed an area of heavy rain from clouds located about 15 miles west of his position. He decided to land as soon as possible due to the deteriorating weather. Instead of making an approach to the airport's single runway, he decided to land toward the west in an open pasture area that was located on the airport property. Shortly after clearing trees and hangars that were located on the east side of the airport, the weight-shift-control aircraft suddenly lost altitude, from about 20 feet agl, and impacted the ground in an upright attitude. After the impact, the aircraft rolled over onto its left side. The pilot reported that the aircraft did not appear to have any forward velocity when it impacted terrain, as indicated by a lack of damage to the surrounding vegetation. The aircraft sustained substantial damage to the wing and fuselage. He stated that there were no mechanical malfunctions of the aircraft that would have precluded normal operation. Additionally, he reported that the aircraft's operating limitations included a maximum headwind and crosswind component of 21 knots and 11 knots, respectively. Meteorological data collected during the accident investigation indicated that, at the time of the accident, there was a squall line of strong-to-severe thunderstorms within a few miles of the accident site. Local weather stations indicated that there was a wind shift from the south to the north that was associated with the passage of the frontal boundary. The weather stations also reported wind gusts reaching 24 knots. A review of weather radar imagery indicated that, at the time of the pilot's preflight weather check, there was a line of thunderstorms located about 40 miles northwest of the departure airport. The same line of thunderstorms was within a few miles of the airport at the time of the accident and moved through the area almost immediately thereafter. The meteorological data suggested that the aircraft likely encountered a gust front that was associated with approaching line of thunderstorms. Although the pilot checked the weather before departure, his failure to correctly identify the location and speed of the approaching line of thunderstorms contributed to the low-level wind shear encounter shortly before touchdown. ## Factual narrative The pilot stated that, about 45 minutes before departure, he obtained current weather conditions via an internet website and observed a thunderstorm located about 100 miles west of the departure airport. The pilot subsequently departed about 0630 for the local area flight. About 20 minutes into the flight, he recalled seeing a low cloud bank, with a base of about 1,000 feet above ground level (agl), about 1/4 mile east of the airport. At the same time, he noticed an area of heavy rain from clouds located about 15 miles west of his position. He decided to land as soon as possible due to the deteriorating weather. Instead of making an approach to the airport's single runway (17/35), he decided to land toward the west in an open pasture area that was located on the airport property. Shortly after clearing trees and hangars that were located on the east side of the airport, the weight-shift-control aircraft suddenly lost altitude, from about 20 feet agl, and impacted the ground in an upright attitude. After the impact, the aircraft rolled over onto its left side. The pilot reported that the aircraft did not appear to have any forward velocity when it impacted terrain, as indicated by a lack of damage to the surrounding vegetation. The aircraft sustained substantial damage to the wing and fuselage. He stated that there were no mechanical malfunctions of the aircraft that would have precluded normal operation. Additionally, he reported that the aircraft's operating limitations included a maximum headwind and crosswind component of 21 knots and 11 knots, respectively.Meteorological data collected during the accident investigation indicated that, at the time of the accident, there was a squall line of thunderstorm activity present within a few miles of the accident site. Additionally, the National Weather Service (NWS) Storm Prediction Center had issued a warning for the development of severe thunderstorms. The NWS storm warning called for scattered strong-to-severe thunderstorms associated with the passage of a cold front. Local weather stations indicated that there was a wind shift from the south to the north that was associated with the passage of the frontal boundary. The weather stations also reported wind gusts reaching 24 knots. A review of weather radar imagery indicated that, at the time of the pilot's preflight weather check, there was a line of thunderstorms located about 40 miles northwest of the departure airport. The same line of thunderstorms was within a few miles of the airport at the time of the accident and moved through the area almost immediately thereafter. ## Aircraft - Registration: [N2017A](https://openairdocs.org/deregistered/N2017A-2022-11-05), registration cancelled 2022-11-05, S/N 582-587, built 2007 (OpenAirDocs) - Reported make and model: AIRBORNE EDGE X - Registry model: [Airborne EDGE X](https://openairdocs.org/model/airborne-edge-x) (registry code 0590083) (OpenAirDocs) - Registry engine: [Rotax 582UL](https://openairdocs.org/engine/rotax-582ul) (registry code 55558, 2 cycle) (OpenAirDocs) - Category: Weight-shift - Serial number: 582-587 - Year built: 2007 - Airframe hours: 431 - Engines: Rotax 582 65 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental light sport (Special) - Last inspection: Condition, April 14, 2014 - Departed: 1H5, Willow Springs, MO - Destination: 1H5, Willow Springs, MO - Airport: 1H5, Willow Springs Memorial - Equipment: Handheld GPS, Airframe parachute ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 67; injuries: minor; sport pilot; medical: sport pilot; last flight review October 24, 2012; seat: front; restraint: lap only; flight hours: 496 total, 356 in this make and model, 466 as pilot in command, 7 in the last 90 days, 2 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 200° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 72 °F, dew point 70 °F - Altimeter: 30.02 inHg - Observed at: UNO, 7 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 20140901021299A](https://openairdocs.org/incident/20140901021299A), Sep 1, 2014: Airborne EDGE X, Willow Spring, MO, Substantial damage. During the landing phase at approximately 0.1 miles from the runway, the pilot experienced mild turbulence. While trying to land at about 20 ft AGL, the… ## Docket (4 files) The files NTSB released with the investigation on March 9, 2015, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=90399. 4.3 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 434 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40423257&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Memorandum of Conversation - James Vokac (item 2, .PDF, 125 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40423258&FileExtension=.PDF&FileName=Memorandum%20of%20Conversation%20-%20James%20Vokac-Master.PDF - Meteorological Report (item 3, .PDF, 3.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40423259&FileExtension=.PDF&FileName=Meteorological%20Report-Master.PDF - Photo 1 - Accident Site Overview (item 4, .PDF, 61 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40423261&FileExtension=.PDF&FileName=Photo%201%20-%20Accident%20Site%20Overview-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.