# NTSB CEN18FA217: Let L 23 Super Blanik, N317BA, Moose, WY, June 9, 2018

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: June 9, 2018, 11:15 local (17:15 UTC)
- Place: Moose, WY
- Coordinates: 43.724723, -110.819168 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=43.7247&lon=-110.8192&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Defining event: [Maneuvering-low-alt flying: Loss of control in flight](https://openairdocs.org/ntsb-events/240)
- Highest injury: Fatal
- Injuries: 2 fatal
- Status: Completed, report August 11, 2020
- Report: Approved by Office Director
- NTSB office: Central Region
- Parties: Teton Aviation Center, FAA Salt Lake City FSDO, Blanik Aircraft CZ s.r.o., Air Accidents Investigation Institute
- NTSB case key (mKey): 97436
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN18FA217
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/97436/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=97436
- Page: https://openairdocs.org/ntsb/CEN18FA217

## Probable cause

The pilot's encounter with atmospheric conditions that resulted in a loss of lift and a subsequent loss of control near terrain that precluded recovery. Contributing to the accident was the pilot's failure to follow the operator's published tour flight procedures regarding flight over the national park and minimum altitudes over and distance from terrain.

## Findings

NTSB's coded findings; those marked are part of the probable cause.

- [Info processing/decision: decision making/judgment](https://openairdocs.org/ntsb-findings/02041520): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Let L-23 SUPER BLANIK, 2 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md?model=1360308), [All aircraft, 3,098 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md)
- [Performance/control parameters: altitude](https://openairdocs.org/ntsb-findings/01062012): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Let L-23 SUPER BLANIK, 2 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md?model=1360308), [All aircraft, 1,310 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md)
- [Performance/control parameters: heading/course](https://openairdocs.org/ntsb-findings/01062047): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Let L-23 SUPER BLANIK, 1 case](https://openairdocs.org/ntsb-findings/01062047/cases.md?model=1360308), [All aircraft, 82 cases](https://openairdocs.org/ntsb-findings/01062047/cases.md)
- [Wind](https://openairdocs.org/ntsb-findings/03034000): Environmental issues › Conditions/weather/phenomena · Effect on operation (probable cause); cases with it: [Let L-23 SUPER BLANIK, 2 cases](https://openairdocs.org/ntsb-findings/03034000/cases.md?model=1360308), [All aircraft, 110 cases](https://openairdocs.org/ntsb-findings/03034000/cases.md)
- [Use of equip/info: use of policy/procedure](https://openairdocs.org/ntsb-findings/02063032): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Let L-23 SUPER BLANIK, 2 cases](https://openairdocs.org/ntsb-findings/02063032/cases.md?model=1360308), [All aircraft, 191 cases](https://openairdocs.org/ntsb-findings/02063032/cases.md)
- [Planning/preparation: flight planning/navigation](https://openairdocs.org/ntsb-findings/02061025): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Let L-23 SUPER BLANIK, 1 case](https://openairdocs.org/ntsb-findings/02061025/cases.md?model=1360308), [All aircraft, 179 cases](https://openairdocs.org/ntsb-findings/02061025/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: Miscellaneous/other](https://openairdocs.org/ntsb-events/900); cases with it: [Let L-23 SUPER BLANIK, 2 cases](https://openairdocs.org/ntsb-events/900/sequence.md?model=1360308), [All aircraft, 1,556 cases](https://openairdocs.org/ntsb-events/900/sequence.md)
- [Maneuvering-low-alt flying: Other weather encounter](https://openairdocs.org/ntsb-events/400); cases with it: [Let L-23 SUPER BLANIK, 3 cases](https://openairdocs.org/ntsb-events/400/sequence.md?model=1360308), [All aircraft, 1,127 cases](https://openairdocs.org/ntsb-events/400/sequence.md)
- [Maneuvering-low-alt flying: Loss of control in flight](https://openairdocs.org/ntsb-events/240) (defining event); cases with it: [Let L-23 SUPER BLANIK, 3 cases](https://openairdocs.org/ntsb-events/240/sequence.md?model=1360308), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md)
- [Maneuvering-low-alt flying: Attempted remediation/recovery](https://openairdocs.org/ntsb-events/060); cases with it: [Let L-23 SUPER BLANIK, 1 case](https://openairdocs.org/ntsb-events/060/sequence.md?model=1360308), [All aircraft, 1,422 cases](https://openairdocs.org/ntsb-events/060/sequence.md)
- [Maneuvering-low-alt flying: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Let L-23 SUPER BLANIK, 10 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=1360308), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md)

## Analysis

The pilot and one passenger departed on a sightseeing tour flight in the glider. After being released from the tow airplane about 13,800 ft mean sea level (msl), the glider pilot proceeded to fly over a national park near mountainous terrain. A video recording of the flight from the passenger's cell phone recorded the pilot state, "this is not good" twice and "I'm in trouble" as the glider neared the terrain. The glider impacted terrain between two mountain peaks (elevations about 12,800 ft msl and 12,500 ft msl) at an elevation about 11,000 ft msl. A review of weather data found upper level winds were from the south-southwest, which likely provided no significant orographic lift in the area of the accident site on the western side of the mountains and likely provided some downdraft activity due to the range immediately south. It is likely that the pilot maneuvered the glider close to terrain in an attempt to attain lift, but encountered atmospheric conditions that resulted in a loss of lift, a loss of control, and a subsequent impact with terrain. According to the operator's tour flight procedures, aircraft were not permitted to fly within the boundaries of the national park and were to maintain a minimum altitude of 2,000 ft above terrain. It is likely that compliance with the company's published procedures would have ensured terrain separation during the flight even in the event of an encounter with adverse wind conditions.

## Factual narrative

Previous Flight The day before the accident, the pilot flew with another passenger and provided a sightseeing tour flight. The passenger reported that the flight consisted of four passes on the backside of the Teton mountain range in the Grand Teton National Park, and provided various photos he took during the flight showing the proximity to terrain, as shown in Figure 3. Figure 3: Aerial View of Terrain, captured the day before the accident flight During the flight, the pilot talked with the passenger about his lack of interest in roller coasters. The pilot asked the passenger what kind of tour flight he would like to receive. He reported that she jokingly asked if he wanted a "rock and roll flight." The passenger responded that he wanted the relaxing version of the tour flight. The passenger described the pilot as a "very competent" pilot who had "smooth flying skills." He reported the overall flight was "peaceful and enjoyable." The LET L-23 Super Blaník Sailplane Flight Manual stated: The LET L-23 Super Blaník sailplane is a cantilever, high-wing, two-seat glider of all-metal structure with fabric covered control surfaces. Both flight compartments are covered by a single-section canopy which may be emergency jettisoned in flight. Both cockpits are equipped with all sailplane flight control including flight and navigation instrument panels. The operator kept the glider fully assembled. Review of weight and balance information revealed that, with the pilot and passenger onboard, the glider was within weight and balance limitations for the flight. Review of the glider's maintenance records revealed no evidence of uncorrected mechanical discrepancies. On June 9, 2018, about 1115 mountain daylight time, a LET L-23 glider, N317BA, was destroyed when it was involved in an accident near Moose, Wyoming. The pilot and passenger sustained fatal injuries. The glider was operated as a Title 14 Code of Federal Regulations (CFR) Part 91 sightseeing flight. The glider was operated by Teton Aviation Center (TAC), based at Driggs-Reed Memorial Airport (DIJ), Driggs, Idaho. The accident flight was a sightseeing flight to view the Teton Range . The operator reported that a sightseeing flight was typically about 1 hour in duration; the first 30 minutes was conducted under tow before the glider released and spent the remaining 30 minutes gliding back to DIJ. The tour predominately flew over the Caribou-Targhee National Forest, encompassing both Idaho and Wyoming. The tow pilot reported that he and the glider pilot discussed the planned route and briefed safe altitudes for the flight, and then completed the preflight duties for the glider together. After departing from DIJ, the tow airplane and glider proceeded south and climbed to 11,000 ft mean sea level (msl) and turned west toward Darby Canyon. The aircraft arrived at the foothills of Darby Canyon at 11,500 ft msl and the tow pilot reported that "there wasn't much lift." They then flew east toward the boundaryof Grand Teton National Park, gaining "a little lift" off the various ridgelines. The tow pilot reported that, prior to reaching the park boundary, they flew north, paralleling the Teton Range, and were "slowly climbing." About 3 miles west of the South Teton peak, at an altitude of 13,800 ft msl, the glider pilot released from tow at 1037. The tow pilot visually confirmed the release in his rearview mirror and returned to DIJ, where he landed about 1045. The tow pilot reported that he maintained radio communication with the glider pilot throughout the tow and that they worked together to find lift to gain sufficient altitude for release. The tow pilot did not report any anomalies with the glider during the tow. The passenger's cell phone was recovered from the accident site and a video recording of the accident flight was retrieved. The recording, taken from the front seat by the passenger, began when the glider was near the Teton Range during the flight, flying over Grand Teton National Park. After about 2 minutes, the footage showed Middle Teton in front of the glider and off to the left; the glider was nearly level with the top of Middle Teton. The pilot stated "this is not good.". The glider then banked slightly right parallel to the ridgeline of Middle Teton. The last frame where the airspeed indicator was visible showed an indicated airspeed of about 42 kts. The top of the ridgeline was above the altitude of the glider. The glider then appeared to enter a steep descent. The pilot again stated "this is not good." The glider appeared to exit the steep descent as it passed by a cliff marking the end of the ridgeline. The glider then appeared to enter another steep descent. The pilot stated, "I'm in trouble." The glider returned to a neutral pitch attitude but appeared to be descending. The glider was traveling along the ridgeline between Middle Teton and South Teton. As the glider descended, it began a right turn pointing toward the ridgeline. In the last frame before the recording ended, the yaw string mounted in front of the passenger's windshield was hanging about 45° to the right. When the flight did not return as expected, TAC personnel attempted to reach the glider pilot via radio. At 1220, the glider was reported overdue to the Federal Aviation Administration (FAA), and an alert notice was subsequently issued. A National Park Service (NPS) search and rescue team consisting of NPS rangers from Jenny Lake Rescue, working in conjunction with Teton County (Wyoming) Search and Rescue, used cell phone data to determine the last known coordinates of the glider. The owner of TAC departed from DIJ about 1435 in a private helicopter and flew to the area of the last known coordinates, where he located the wreckage in steep mountainous terrain about 11,000 ft msl, between Middle Teton peak (12,809 ft msl) and South Teton peak (12,519 ft msl) near the frozen Icefloe Lake in Grand Teton National Park, as shown in Figure 1. Figure 1: Accident SiteLocation Teton Pathology, Jackson, Wyoming, conducted an autopsy of the pilot. The cause of the death was attributed to multiple blunt force injures. The autopsy revealed no significant natural disease that could pose a hazard to flight safety. The FAA's Forensic Sciences Laboratory performed toxicology tests on specimens from the pilot; testing was negative for ethanol and drugs. A test for carbon monoxide and cyanide was not performed. The National Weather Service (NWS) Storm Prediction Center's forecast upper air constant pressure charts for 0600 showed the conditions at about 10,000 ft and 18,000 ft msl. The charts depicted a long wave trough over the western United States with southwesterly winds over Idaho and Wyoming; wind speeds increased with height with little change in direction. The front side of an upper level trough implies upper-level divergence and general rising motion of the area and the development of clouds and precipitation if adequate moisture is available. Upper level troughs also support surface fronts. AIRMET Tango was current for moderate turbulence below 16,000 ft over a large portion of the central and southwestern United States. The accident site was located within the boundary of the advisory area. High-Resolution Rapid Refresh numerical model data was plotted and indicated a lifted condensation level (LCL) about 3,200 ft agl. The profile below 10,000 ft was characterized as conditional unstable with a Lifted Index of -1. The sounding thermal structure did not support any strong thermal activity. The sounding profile indicated that the glider likely encountered southerly winds from 185° at 25 to 27 knots, with the potential for light turbulence at 12,700 ft msl. With this wind direction, no significant orographic lift would be generated on the western slopes of the Teton Mountain Range. There was no record that the pilot obtained a preflight weather briefing from the FAA contract Automated Flight Service Station (AFSS) provider, Leidos, or from a third-party provider. It could not be determined what weather information the pilot may have reviewed before departure. The 14 CFR Part 91 Letter of Authorization for Teton Aviation Center was managed by the FAA Salt Lake City Flight Standards District Office, Salt Lake City, Utah. FAA Letters of Authorization for sightseeing tour flights only include powered aircraft (such as airplanes and helicopters). Non-powered aircraft, such as gliders or balloons, are not included. The TAC Standard Operating Procedures (SOP) discussed sightseeing tour flights and stated in part: Teton Aviation Center scenic flights are operated under §119.1(e)(2) and a Letter of Authorization under 91.147, which authorize us to conduct non-stop scenic air tours within a 25 nautical mile radius of the Driggs airport (KDIJ). We do not have authorization to overfly Grand Teton National Park, and are required to remain at least ½ mile outside Park boundaries. Minimum altitude is 2000' AGL [above groundlevel] over mountainous terrain. No TAC aircraft may be flown below 500' above ground (AGL) unless it is taking off or landing. Maneuvers require at least 2000'AGL unless otherwise specified on TAC maneuver summary sheets, or the FAA Practical Test Standard (PTS). Glider pilots are required to adhere to the minimum station altitudes. The pilot previously held an FAA second class medical certificate, which expired on June 20, 2016. Glider operations under 14 CFR Part 91, including personal flights, flight instruction, and sightseeing tour flights, do not require the pilot to hold an FAA medical certificate. TAC reported the pilot was hired in March 2001. Since the date of hire, she flew 650 hours of instruction in the glider and flew 559 sightseeing tour flights in the glider. The pilot's most recent recurrency flight was conducted on April 27, 2018. In postaccident interviews, TAC personnel described the pilot as, "very safety conscious," "very by the book," "very cautious," and "always thorough." The pilot's husband reported that she never expressed any concerns about working at TAC and she "enjoyed taking passengers on flights and working with her coworkers." Photos provided by the NPS showed both wings and an impact crater located on a west-facing, snow and ice-covered saddle, which originated at South Teton Peak and extended to the northeast, culminating at Middle Teton peak. The photos showed the fuselage, empennage, and miscellaneous debris located near the base of the saddle by Icefloe Lake. Figure 2: Accident Site The wreckage was extracted via external load with an NPS-contracted helicopter to a secure location for a wreckage layout and examination. All major structural components of the glider were accounted for. Flight control continuity was established throughout the airframe, and no preimpact mechanical malfunctions or failures with the glider were noted.

## Aircraft

- Registration: [N317BA](https://openairdocs.org/deregistered/N317BA-2021-02-26), registration cancelled 2021-02-26, S/N 978406, built 1997 (OpenAirDocs)
- Reported make and model: LET L 23 SUPER BLANIK (NO SERIES)
- Registry model: [Let L-23 SUPER BLANIK](https://openairdocs.org/model/let-l-23-super-blanik) (registry code 1360308) (OpenAirDocs)
- Registry engine: [NONE](https://openairdocs.org/engine/none) (registry code 00000, none) (OpenAirDocs)
- Category: Glider
- Serial number: 978406
- Year built: 1997
- Airframe hours: 3782.9
- Damage: Destroyed
- Flight: Business, Part 91
- Operator: Teton AvJet, LLC, doing business as Teton Aviation Center
- Registered owner: Teton AvJet, LLC
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, February 23, 2018
- Departed: DIJ, DRIGGS, ID
- Destination: DIJ, DRIGGS, ID
- Equipment: None

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 65; injuries: fatal; flight instructor, commercial; airplane ratings: single-engine land; medical: class 2, with waivers/limitations; last flight review April 30, 2017; seat: rear; restraint: 4-point; toxicology performed; flight hours: 1,200 total

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 64 °F, dew point 45 °F
- Altimeter: 30.04 inHg
- Turbulence: Moderate
- Observed at: KJAC, 8 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 20180609015419A](https://openairdocs.org/incident/20180609015419A), Jun 9, 2018: Let L-23 SUPER BLANIK, Moose, WY, Destroyed, 2 fatal. At approximately 09:15 local the airman arrived at the airport and prepared for a scenic flight. At approximately 09:50 local the glider was launched via…

## Docket (30 files)

The files NTSB released with the investigation on July 20, 2020, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=97436. 29.0 MB in all.

- Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 11.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485385&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF
- TAC NTSB Party Member Forms (item 2, .PDF, 669 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485386&FileExtension=.PDF&FileName=TAC%20NTSB%20Party%20Member%20Forms%20-Master.PDF
- TAC Company Interviews (item 3, .PDF, 496 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485387&FileExtension=.PDF&FileName=TAC%20Company%20Interviews%20-Master.PDF
- TAC Dispatch Statement LeeAnn Ulrichs (item 4, .PDF, 83 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485388&FileExtension=.PDF&FileName=TAC%20Dispatch%20Statement%20LeeAnn%20Ulrichs%20-Master.PDF
- TAC Tow Pilot Sonny Knowles Additional Questions (item 5, .PDF, 59 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485389&FileExtension=.PDF&FileName=TAC%20Tow%20Pilot%20Sonny%20Knowles%20Additional%20Questions%20-Master.PDF
- Ned Martin Record of Conversation (item 6, .PDF, 101 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485390&FileExtension=.PDF&FileName=Ned%20Martin%20Record%20of%20Conversation%20-Master.PDF
- Vicki Ross Record of Conversation (item 7, .PDF, 104 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485391&FileExtension=.PDF&FileName=Vicki%20Ross%20Record%20of%20Conversation-Master.PDF
- Norman Bailey Record of Conversation (item 8, .PDF, 111 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485392&FileExtension=.PDF&FileName=Norman%20Bailey%20Record%20of%20Conversation%20-Master.PDF
- Ed Crawley Record of Conversation (item 9, .PDF, 108 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485393&FileExtension=.PDF&FileName=Ed%20Crawley%20Record%20of%20Conversation%20-Master.PDF
- Peter Kline Record of Conversation (item 10, .PDF, 101 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485399&FileExtension=.PDF&FileName=Peter%20Kline%20Record%20of%20Conversation%20-Master.PDF
- TAC Pilot's Currency Record (item 11, .PDF, 103 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485400&FileExtension=.PDF&FileName=TAC%20Pilot%27s%20Currency%20Record%20-Master.PDF
- TAC Pilot's Training Record (item 12, .PDF, 93 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485401&FileExtension=.PDF&FileName=TAC%20Pilot%27s%20Training%20Record%20-Master.PDF
- TAC Glider Flight Log (item 13, .PDF, 161 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485402&FileExtension=.PDF&FileName=TAC%20Glider%20Flight%20Log%20-Master.PDF
- TAC Weight and Balance Documents (item 14, .PDF, 3.8 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485403&FileExtension=.PDF&FileName=TAC%20Weight%20and%20Balance%20Documents%20-Master.PDF
- TAC Maintenance Records (item 15, .PDF, 345 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485404&FileExtension=.PDF&FileName=TAC%20Maintenance%20Records%20-Master.PDF
- TAC Glider Passenger Briefing (item 16, .PDF, 98 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485405&FileExtension=.PDF&FileName=TAC%20Glider%20Passenger%20Briefing%20-Master.PDF
- TAC Glider Flight Tour Route and Altitudes (item 17, .PDF, 1.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485406&FileExtension=.PDF&FileName=TAC%20Glider%20Flight%20Tour%20Route%20and%20Altitudes%20-Master.PDF
- TAC Internet Website Screenshots - Tips for Pilots (item 18, .PDF, 185 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485407&FileExtension=.PDF&FileName=TAC%20Internet%20Website%20Screenshots%20-%20Tips%20for%20Pilots%20-Master.PDF
- FAA Toxicology Report (item 19, .PDF, 67 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485408&FileExtension=.PDF&FileName=FAA%20Toxicology%20Report%20-Master.PDF
- Accident Site Location (item 20, .PDF, 247 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485409&FileExtension=.PDF&FileName=Accident%20Site%20Location-Master.PDF
- Accident Site and Wreckage Locations (item 21, .PDF, 121 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485410&FileExtension=.PDF&FileName=Accident%20Site%20and%20Wreckage%20Locations-Master.PDF
- FAA TAC 14 CFR Part 91 Letter of Authorization (item 22, .PDF, 3.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485411&FileExtension=.PDF&FileName=FAA%20TAC%2014%20CFR%20Part%2091%20Letter%20of%20Authorization%20-Master.PDF
- Soaring Society of America Information Request (item 23, .PDF, 84 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485412&FileExtension=.PDF&FileName=Soaring%20Society%20of%20America%20Information%20Request%20-Master.PDF
- Soaring Magazine Article - September 1984 (item 24, .PDF, 899 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485413&FileExtension=.PDF&FileName=Soaring%20Magazine%20Article%20-%20September%201984-Master.PDF
- Weather Study (item 25, .PDF, 2.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485419&FileExtension=.PDF&FileName=Weather%20Study-Master.PDF
- Attachment 1 - TAC Tow Pilot, Sonny Knowles Statement (item 26, .PDF, 173 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485421&FileExtension=.PDF&FileName=Attachment%201%20-%20TAC%20Tow%20Pilot,%20Sonny%20Knowles%20Statement-Master.PDF
- Attachment 2 - James Markowitz Record of Conversation (item 27, .PDF, 147 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485433&FileExtension=.PDF&FileName=Attachment%202%20-%20James%20Markowitz%20Record%20of%20Conversation-Master.PDF
- Nathan Foote Record of Conversation (item 28, .PDF, 108 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485434&FileExtension=.PDF&FileName=Nathan%20Foote%20Record%20of%20Conversation-Master.PDF
- Nathan Foote Photographs (item 29, .PDF, 614 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485435&FileExtension=.PDF&FileName=Nathan%20Foote%20Photographs%20-Master.PDF
- Personal Electronic Device Specialist's Factual Report (item 30, .PDF, 1.8 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485436&FileExtension=.PDF&FileName=Personal%20Electronic%20Device%20Specialist%27s%20Factual%20Report-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.

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