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SEA96FA186 · Let L-13

10 Aug 1996 · Shelton, WA, United States

Let L-13 · Accident: loss of control in flight while maneuvering

From Sanderson Field (SHN) to an unrecorded destination

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Event

NTSB case
SEA96FA186
Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
Accident
InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
Completed
API-reported fatalities
1 · all aircraft and ground
Ground fatalities
0
OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
General aviation
WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
Visual Meteorological Cond

Let L-13

Aircraft type
Let L-13
Category
Glider
RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
N90865
Operator
Unknown
Onboard fatalities
Unknown
Route
From Sanderson Field (SHN)To not recorded
Aircraft age
Not recorded
Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
Part 91: General Aviation
Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
Maneuvering
First occurrenceThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
Loss of control in flight
Also codedOther events the NTSB coded in the sequence, such as a wire strike after a loss of power. Flight Findings uses them for its kinds of event. Glossary
Stall/spin
DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
Substantial

Cause areas

  • Aircraft weight and balance › Exceeded
  • Company/operator management › Information, not issued
  • Pilot in command › Stall/spin, encountered

Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.

NTSB narrative

After receiving a glider certification on 7/24/96, the pilot (plt) logged about 2.1 hrs in a Let L-13 glider, before flying it solo. The initial solo was the accident flight (flt) on 8/10/96. On this flight, the plt planned to be towed to traffic pattern altitude, then release the glider, enter the traffic pattern, & land. Release occurred about 3 mi southwest of the airport at 1,850 ft. Airport elevation was 269 ft. Witnesses said the L-13 entered a right spin about 5 to 10 sec after release & continued spinning until ground impact. To keep the center-of-gravity (CG) from exceeding the aft limit, a placard had been installed in the cockpit, indicating the minimum front seat solo weight to be 150 lbs. The L-13's operating manual contained this & other info based on the L-13's original weight & balance (W/B) configuration. The plt weighed between 128 & 135 lbs, & a single 25 lb ballast bag was found in the wreckage. However, after repainting & modification with a non-standard tailwheel, the glider's revised W/B data indicated the current minimum front seat solo weight was 181 lbs. Based on this info (kept in the operator's maintenance shop), the glider's C.G. was computed to be 1.4 inches behind the aft limit. The plt's personal copy of the L-13 operating manual did not contain the revised W/B data. Copies of the glider's operating manual were being sold to renters without this info.

Probable cause

failure of the operator to provide its pilots with information essential for an accurate determination of the glider's weight and balance, the resultant operation of the glider with a center-or-gravity that exceeded the aft limit, and the pilot's inadvertent entry into a stall/spin. Factors relating to the accident were: an incorrect placard concerning the glider's minimum front seat solo weight limitation, and the pilot's lack of experience in the make and model of aircraft.

Verbatim NTSB analysis and probable cause from the NTSB dataset

Sources

NTSB record SEA96FA186
Event ID
20001208X06614
Case number
SEA96FA186
Dataset
historical-pre2008
Source SHA-256
89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (4)
  • Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
  • Filled from the NTSB case API where the bulk record had no value: local date, investigation status. Values present in the bulk record are kept.
  • The date is the local date; the NTSB stores the UTC date 1996-08-11.
  • API snapshot SHA-256: 210289d85af7553368bbb86d04f36552bf28c1ba2ebce09d898e898a94e92621; retrieved 2026-09-20T23:13:44.578Z.