Wednesday, March 03, 2021

Loss of Control in Flight: LET L-23 Super Blanik, N296BA; accident occurred March 01, 2020 near Moontown Airport (3M5), Brownsboro, Madison County, Alabama


View of glider as found facing approximate direction of travel

View of glider as found facing opposite direction of travel

Wreckage Diagram/Airport View

Aviation Accident Final Report - National Transportation Safety Board

Additional Participating Entity:
Federal Aviation Administration / Flight Standards District Office; Birmingham, Alabama

Investigation Docket - National Transportation Safety Board:

Location: Huntsville, AL
Accident Number: ERA20CA116
Date & Time: 03/01/2020, 1400 CST
Registration: N296BA
Aircraft: Let L 23 SUPER BLANIK
Aircraft Damage: Substantial
Defining Event: Loss of control in flight
Injuries: 2 Serious
Flight Conducted Under: Part 91: General Aviation - Instructional


According to the glider pilot, the purpose of the flight was to release from the tow about 300 ft above ground level, return to the airport, and land on the departure runway in the opposite direction, which would simulate the response to a "rope-break" emergency during the initial climb. After departure from the runway and release from the tow, the pilot completed a 270° turn on the north side of the runway and had to make another 90°, left base-to-final turn to return toward the runway. While still on the base leg, the glider encountered an 11-knot wind from the south, gusting to 18 knots. The pilot believed that the glider must have encountered "wind shear" as he "lost all elevator control," and the glider then impacted terrain. The Federal Aviation Administration inspector who conducted a postaccident examination of the glider reported that he established flight control continuity. The pilot reported that there were no preaccident mechanical malfunctions or failures with the glider that would have precluded normal operation.

Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be:
The pilot's failure to maintain glider control and his exceedance of the glider's critical angle of attack while maneuvering in gusting wind conditions, which resulted in an aerodynamic stall.


Personnel issues Aircraft control - Pilot
Aircraft Angle of attack - Capability exceeded
Environmental issues Gusts - Effect on operation

Factual Information

History of Flight

Approach Other weather encounter
Approach Loss of control in flight (Defining event)
Approach Collision with terr/obj (non-CFIT)

Pilot Information

Certificate: Flight Instructor; Commercial; Private
Age: 69, Male
Airplane Rating(s): Multi-engine Land; Single-engine Land
Seat Occupied: Rear
Other Aircraft Rating(s): Glider
Restraint Used:
Instrument Rating(s): Airplane
Second Pilot Present: No
Instructor Rating(s): Glider
Toxicology Performed: No
Medical Certification: Class 3 With Waivers/Limitations
Last FAA Medical Exam: 04/23/2019
Occupational Pilot: No
Last Flight Review or Equivalent:
Flight Time:  1834 hours (Total, all aircraft), 295 hours (Total, this make and model) 

Aircraft and Owner/Operator Information

Aircraft Make: Let
Registration: N296BA
Model/Series: L 23 SUPER BLANIK No Series
Aircraft Category:Glider
Year of Manufacture: 1994
Amateur Built:No
Airworthiness Certificate: Normal
Serial Number: 948117
Landing Gear Type: Tandem
Seats: 2
Date/Type of Last Inspection: 03/30/2019, Annual
Certified Max Gross Wt.:
Time Since Last Inspection: 90 Hours
Airframe Total Time: 1680 Hours at time of accident
Engine Manufacturer:
ELT: Not installed
Engine Model/Series:
Registered Owner: Huntsville Soaring Club
Rated Power:
Operator: Huntsville Soaring Club
Operating Certificate(s) Held: None

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: KMDQ, 763 ft msl
Distance from Accident Site: 8 Nautical Miles
Observation Time: 1955 UTC
Direction from Accident Site: 325°
Lowest Cloud Condition: Clear
Visibility:  10 Miles
Lowest Ceiling: None
Visibility (RVR):
Wind Speed/Gusts: 11 knots / 18 knots
Turbulence Type Forecast/Actual:
Wind Direction: 190°
Turbulence Severity Forecast/Actual:
Altimeter Setting: 30.12 inches Hg
Temperature/Dew Point: 19°C / 3°C
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: Huntsville, AL (3M5)
Type of Flight Plan Filed: None
Destination: Huntsville, AL (3M5)
Type of Clearance: None
Departure Time:  CST
Type of Airspace: Class G

Airport Information

Airport: Moontown (3M5)
Runway Surface Type: Grass/turf
Airport Elevation: 655 ft
Runway Surface Condition:Dry 
Runway Used: 09
IFR Approach: None
Runway Length/Width: 2180 ft / 160 ft
VFR Approach/Landing: Simulated Forced Landing 

Wreckage and Impact Information

Crew Injuries: 1 Serious
Aircraft Damage: Substantial
Passenger Injuries: 1 Serious
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries:2 Serious 
Latitude, Longitude: 34.747222, -86.460833 (est)

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