# NTSB SEA87LA012: Let L-13, N2NV, Boulder City, NV, October 12, 1986

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Limited investigation · Final report
- Date: October 12, 1986, 13:25 local (20:25 UTC)
- Place: Boulder City, NV
- Coordinates: 35.990074, -114.809455 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=35.9901&lon=-114.8095&mi=10
- Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 1 serious, 1 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 40557
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA87LA012
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/40557/pdf
- Page: https://openairdocs.org/ntsb/SEA87LA012

## Sequence of events

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

- Undershoot, approach - vfr pattern - base leg/base to final
  - weather condition - downdraft (contributing factor)
  - compensation for wind conditions - improper, pilot in command (cause)
  - proper descent rate - exceeded, pilot in command (cause)
  - improper use of procedure, pilot in command (cause)
  - proper altitude - not maintained, pilot in command (cause)
  - ostentatious display, pilot in command (cause)
- In flight collision with terrain/water, approach - vfr pattern - base leg/base to final

## Analysis

THE PLT STATED THAT A DOWNDRAFT WAS ENCOUNTERED AND AN UNDERSHOOT OCCURRED WHILE ON BASE LEG. A HIGH SINK RATE DEVELOPED AND THE PLT DID NOT TAKE CORRECTIVE ACTION SOON ENOUGH. THE ACFT STRUCK THE GROUND, ROLLED A SHORT DISTANCE THROUGH BUSHES, AND ACROSS A TWO FOOT GULLEY BEFORE COMING TO REST. THE PASSENGER STATED THAT THE PLT ENTERED INTO AN INTENTIONAL SPIN WHILE IN THE PRACTICE AREA IN ORDER TO SHOW OFF. HE ALSO STATED THAT THE PLT MADE A RATHER RAPID DESCENT BY THE USE OF SPOILERS THAT EXCEEDED THE LIMITS OF THE VERTICAL SPEED INDICATOR.

## Aircraft

- Registration: N2NV (not matched to a registry record)
- Reported make and model: LET L-13
- Category: Glider
- Serial number: 175220
- Airframe hours: 2408
- Engines: unknown
- Damage: Minor damage
- Flight: Part 91
- Registered owner: Stephen Dvorchak
- Airworthiness certificate: Standard, Normal
- Last inspection: 100 hour, May 1, 1986, 93 hours before
- Airport: BLD, Boulder City Municipal, runway 3, 3,100 × 100 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 57; airline transport, flight instructor; airplane ratings: single-engine sea, single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: front; flight hours: 10,348 total, 1,915 in this make and model, 9,539 as pilot in command, 99 in the last 90 days, 3 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 30° at 10 knots, gusting 15
- Visibility: 40 statute miles
- Lowest ceiling: none
- Temperature: 81 °F

## 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 19861012051649A](https://openairdocs.org/incident/19861012051649A), Oct 12, 1986: Let L13BLANIK, Boulder City, NV, Minor damage. The glider impacted the ground short of the runway. The pilot misapplied spoilers in the pattern.

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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