# NTSB DEN77FTE33: Blanik L-13, N3458, Boulder, CO, April 9, 1977

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Closed
- Date: April 9, 1977
- Place: Boulder, CO · BOULDER, CO
- Location: 40.0244° N, 105.2513° W: Placed by OpenAirDocs: center of Boulder, CO, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=40.0244&lon=-105.2513&mi=10
- Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report May 9, 1977
- Report: Brief approved by the director
- NTSB case key (mKey): 157646
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN77FTE33
- Page: https://openairdocs.org/ntsb/DEN77FTE33

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-0520   77/4/9    BOULDER,CO          BLANIK L-13         CR-  0  0  1  NONCOMMERCIAL             PRIVATE, AGE 39, 688
        TIME - 1530                    N3458               PX-  0  0  1  PLEASURE/PERSONAL TRANSP  TOTAL HOURS, 10 IN TYPE,
                                       DAMAGE-SUBSTANTIAL  OT-  0  0  0                            NOT INSTRUMENT RATED.
        NAME OF AIRPORT - BOULDER MUNI
        DEPARTURE POINT             INTENDED DESTINATION
          BOULDER,CO                  LOCAL
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           UNDERSHOOT                                               LANDING: FINAL APPROACH
           GROUND-WATER LOOP-SWERVE                                 LANDING: LEVEL OFF/TOUCHDOWN
        PROBABLE CAUSE(S)
           PILOT IN COMMAND - MISJUDGED DISTANCE AND ALTITUDE
```

## Aircraft

- Registration: [N3458](https://openairdocs.org/deregistered/N3458-1992-10-23), registration cancelled 1992-10-23, S/N 174216 (OpenAirDocs)
- Reported make and model: BLANIK L-13
- Registry model: [Let BLANIK L-13](https://openairdocs.org/model/let-blanik-l-13) (registry code 1360306) (OpenAirDocs)
- Category: Glider
- Engines: none
- Damage: Substantial damage
- Airport: Boulder Muni

## 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 19770409007169A](https://openairdocs.org/incident/19770409007169A), Apr 9, 1977: Let L13BLANIK, Boulder, CO, Substantial damage

## Other investigations on N3458 (1)

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.

- [NTSB DEN89LA210](https://openairdocs.org/ntsb/DEN89LA210), Sep 16, 1989: Let L-13 (N3458), Buena Vista, CO, substantial damage, 1 fatal. Probable cause: A PREMATURE RELEASE OF THE GLIDER TOW LINE BY THE GLIDER PILOT AND HIS FAILURE TO MAINTAIN SUFFICIENT AIRSPEED, WHILE MANEUVERING BACK TOWARD THE RUNWAY, WHICH RESULTED IN AN INADVERTENT STALL.

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.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.