# NTSB CHI91LA231: Let L-13, N781BA, Gregory, MI, July 26, 1991

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: July 26, 1991, 19:30 local (23:30 UTC)
- Place: Gregory, MI
- Coordinates: 42.449554, -84.079421 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=42.4496&lon=-84.0794&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report March 31, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 15129
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI91LA231
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/15129/pdf
- Page: https://openairdocs.org/ntsb/CHI91LA231

## Probable cause

A COLLISION WITH WIRES AFTER THE GLIDER OVERSHOT THE LANDING AREA DUE TO INADVERTENT LOWERING OF THE FLAPS AND NO USE OF SPOILERS.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Miscellaneous/other, landing
  - lowering of flaps - inadvertent activation, pilot in command (cause)
  - spoiler extension - not used, pilot in command (cause)
  - proper glidepath - not attained, pilot in command (cause)
  - remedial action - not performed, pilot in command (cause)
- Overrun, landing - flare/touchdown
- In flight collision with object, landing - flare/touchdown
  - object - wire,static (contributing factor)
- In flight collision with terrain/water, descent - uncontrolled
  - terrain condition - rough/uneven

## Analysis

THE STUDENT GLIDER PILOT SAID THAT HE INADVERTENTLY DEPLOYED THE FLAPS INSTEAD OF THE SPOILERS WHILE MAKING A LANDING APPROACH.  THE GLIDE PATH WAS SHALLOWED AND THE PILOT WAS UNABLE TO LAND ON THE GRASS STRIP.  THE GLIDER OVERSHOT THE RUNWAY AND COLLIDED WITH POWER LINES, THEN THE ROUGH TERRAIN.

## Aircraft

- Registration: [N781BA](https://openairdocs.org/deregistered/N781BA-2013-05-13), registration cancelled 2013-05-13, S/N 025618 (OpenAirDocs)
- Reported make and model: LET L-13
- Registry model: [Let BLANIK L-13](https://openairdocs.org/model/let-blanik-l-13) (registry code 1360306) (OpenAirDocs)
- Registry engine: [NONE](https://openairdocs.org/engine/none) (registry code 00000, none) (OpenAirDocs)
- Category: Glider
- Serial number: 02 56 18
- Airframe hours: 1158
- Engines: unknown
- Damage: Substantial damage
- Flight: Instructional, Part 91
- Operator: Sandhill Soaring Club
- Airworthiness certificate: Standard, Normal
- Last inspection: 100 hour, July 12, 1991, 41 hours before
- Airport: 69G, Richmond, runway 35, 2,252 × 100 ft, grass/turf

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 45; private; medical: unknown; seat: front; flight hours: 20 total, 1 in this make and model, 9 as pilot in command, 5 in the last 90 days, 2 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 350° at 7 knots
- Visibility: 15 statute miles
- Lowest ceiling: none
- Observed at: JXN, 15 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 19910726030209A](https://openairdocs.org/incident/19910726030209A), Jul 26, 1991: Let L13BLANIK, Gregory, MI, Substantial damage. High on final used flaps instead of spoilers. Overflew runway,struck wires and crashed off departure end.

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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