# NTSB LAX95LA050: Burkhart Grob G-103, N3950A, Tehachapi, CA, December 11, 1994

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: December 11, 1994, 14:00 local (22:00 UTC)
- Place: Tehachapi, CA
- Coordinates: 35.120933, -118.5102 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=35.1209&lon=-118.5102&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report April 5, 1995
- Report: Approved by Office Director
- NTSB case key (mKey): 28992
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX95LA050
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/28992/pdf
- Page: https://openairdocs.org/ntsb/LAX95LA050

## Probable cause

the pilot's poor in-flight planning/decision and inadequate airspeed.  The downdraft and trees were factors in this accident.

## Sequence of events

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

- In flight encounter with weather, maneuvering
  - weather condition - downdraft (contributing factor)
  - in-flight planning/decision - poor, pilot in command(cfi) (cause)
- In flight collision with object, maneuvering
  - object - tree(s) (contributing factor)
  - airspeed - inadequate, pilot in command(cfi) (cause)

## Analysis

THE PILOT SAID IN A POSTACCIDENT TELEPHONE INTERVIEW THAT HE WAS RIDGE SOARING ABOUT 100 FEET ABOVE THE TREES ALONG A SOUTHEAST/NORTHWESTERLY COURSE.  THE PILOT SUCCESSFULLY EXECUTED ONE PASS OVER THE RIDGE LINE.  ON THE SECOND PASS, THE FLIGHT ENCOUNTERED A SEVERE DOWNDRAFT.  THE GLIDER'S AIRSPEED WAS INSUFFICIENT TO CLIMB OUT OF THE IMPENDING TREE LINE AND THE GLIDER'S RIGHT WING STRUCK A TREE.  THE PILOT REGAINED CONTROL OF THE GLIDER AND LANDED AT THE AIRPORT WITHOUT FURTHER INCIDENT.

## Factual narrative

On December 11, 1994, at 1400 hours Pacific standard time, a Grob G-103 glider, N3950A, collided with some trees near Tehachapi, California.  The pilot was conducting a local visual flight rules instructional flight.  The glider, operated by Skylark North, Tehachapi, California, sustained substantial damage.  Neither the certificated commercial pilot/certified flight instructor (CFI) nor the certificated private/student glider pilot was injured.  Visual meteorological conditions prevailed.  The flight originated at Mountain Valley Airport, Tehachapi, California, at 1330 hours.

The CFI reported this accident to the National Transportation Safety Board on December 12, 1994.  He said the flight encountered a severe downdraft while maneuvering over a ridge on a southeast/northwest course about 100 feet above the ground.  The glider's right wing struck some trees.  The CFI landed the glider at Mountain Valley Airport without further incident.  Examination of the glider revealed that the right wing sustained structural damage.

The CFI submitted the required Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1/2.  He repeated his telephone statement in the report.  He said that the accident occurred on the second pass over the ridge line.  The first pass was uneventful.

When the glider encountered the downdraft, the airspeed was inadequate to climb successfully over the impending tree line.  The CFI also said that the glider did not experience any mechanical malfunctions or failures.

## Aircraft

- Registration: [N3950A](https://openairdocs.org/aircraft/N3950A), registered now, S/N 3793, built 1983 (OpenAirDocs)
- Reported make and model: Burkhart Grob G-103
- Registry model: [Burkhart Grob G 103 TWIN II](https://openairdocs.org/model/burkhart-grob-g-103-twin-ii) (registry code 1660203) (OpenAirDocs)
- Registry engine: [NONE](https://openairdocs.org/engine/none) (registry code 00000, none) (OpenAirDocs)
- Category: Glider
- Serial number: 3793
- Airframe hours: 4097
- Engines: unknown
- Damage: Substantial damage
- Flight: Instructional, Part 91
- Operator: Skylark North
- Registered owner: Jay Demiranda
- Airworthiness certificate: Standard, Normal
- Last inspection: 100 hour, March 29, 1994, 50 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 36; flight instructor, commercial; airplane ratings: single-engine land; medical: class 2, valid medical--w/ waivers/lim; seat: rear; flight hours: 6,037 total, 520 in this make and model, 5,980 as pilot in command, 130 in the last 90 days, 40 in the last 30 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 280° at 13 knots
- Visibility: 100 statute miles
- Lowest ceiling: none
- Temperature: 50 °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 19941211042729A](https://openairdocs.org/incident/19941211042729A), Dec 11, 1994: Grob G103TWNASTIR, Tehachapi, CA, Substantial damage. Collided with trees. Blamed a severe downdraft circling a ridge.

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.