# NTSB LAX96LA160: Schweizer SGS1-34, N7623, Inyokern, CA, April 7, 1996 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: April 7, 1996, 15:45 local (22:45 UTC) - Place: Inyokern, CA - Coordinates: 35.549175, -117.669044 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=35.5492&lon=-117.6690&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report August 20, 1996 - Report: Approved by Office Director - NTSB case key (mKey): 29411 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX96LA160 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/29411/pdf - Page: https://openairdocs.org/ntsb/LAX96LA160 ## Probable cause the pilot misjudged altitude while maneuvering in mountainous terrain. Contributing factors were: the pilot's inadequate in-flight planning and the lack of available thermal lift over the rapidly rising rough terrain. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight collision with terrain/water, maneuvering - weather condition - no thermal lift (contributing factor) - in-flight planning/decision - inadequate, pilot in command (contributing factor) - terrain condition - rising (contributing factor) - distance/altitude - misjudged, pilot in command (cause) - terrain condition - rough/uneven (contributing factor) ## Analysis The pilot indicated that while soaring over a ridge he turned into a saddle area, and then he turned back toward the ridge. While performing these maneuvers, he encountered a high rate of sink. The pilot reported that he had not allowed sufficient height above the rapidly rising rough terrain to avoid impact. ## Factual narrative On April 7, 1996, at 1545 hours Pacific daylight time, a Schweizer SGS 1-34, N7623, operated by the Sierra Soaring Club and rented by the pilot, collided with terrain near Inyokern, California. Visual meteorological conditions prevailed during the personal flight, and no flight plan was filed. The glider was substantially damaged, and the private pilot was not injured. The flight originated from Inyokern at 1500. The pilot indicated that the accident sequence began while soaring over a ridge. He stated that he turned into a saddle area near the Owens Peak, and then he turned back towards the ridge. While maneuvering, the glider encountered a high rate of sink. In the pilot's completed accident report he wrote the following statement: "I had not allowed sufficient height above the terrain, which was rising at approximately 20 to 30 degrees, to avoid impact." The glider collided with the rapidly rising rough terrain. The pilot indicated that no mechanical malfunctions or failures were experienced during the flight. ## Aircraft - Registration: [N7623](https://openairdocs.org/deregistered/N7623-2013-02-26), registration cancelled 2013-02-26, S/N 3, built 1969 (OpenAirDocs) - Reported make and model: Schweizer SGS1-34 - Registry model: [Schweizer SGS 1-34](https://openairdocs.org/model/schweizer-sgs-1-34) (registry code 8050146) (OpenAirDocs) - Registry engine: [NONE](https://openairdocs.org/engine/none) (registry code 00000, none) (OpenAirDocs) - Category: Glider - Serial number: 3 - Engines: unknown - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Sierra Soaring Club - Airworthiness certificate: Standard, Normal - Last inspection: Annual, December 30, 1995, 4 hours before - Departed: IYK ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 65; private; medical: unknown; seat: front; flight hours: 78 total, 5 in this make and model, 38 as pilot in command, 8 in the last 90 days, 7 in the last 30 days, 3 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 225° at 5 knots - Visibility: 50 statute miles - Lowest ceiling: none - Temperature: 75 °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 19960407006069A](https://openairdocs.org/incident/19960407006069A), Apr 7, 1996: Scwzer SGS134, Inyokern, CA, Substantial damage. Encountered high sink rate below a ridge. Impacted ground. Had failed to allow sufficient altitude for terrain. ## Other investigations on N7623 (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 OAK70DVW23](https://openairdocs.org/ntsb/OAK70DVW23), Jun 24, 1970: Schweizer 1-34 (N7623), Bishop, CA, substantial damage 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.