# NTSB WPR09LA449: Schweizer SGS 1-34, N7656, Lake Elsinore, CA, September 12, 2009 - Type: NTSB accident investigation - Classification: Accident · Fatal · Limited investigation · Final report - Date: September 12, 2009, 14:53 local (21:53 UTC) - Place: Lake Elsinore, CA - Coordinates: 33.630001, -117.301666 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=33.6300&lon=-117.3017&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Defining event: [Initial climb: Glider tow event](https://openairdocs.org/ntsb-events/510) - Highest injury: Fatal - Injuries: 1 fatal - Status: Completed, report April 28, 2011 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 74731 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR09LA449 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/74731/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=74731 - Page: https://openairdocs.org/ntsb/WPR09LA449 ## Probable cause The pilot's failure to maintain control of the glider after the tow line released during the initial climb. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause) - [Fuselage: aerial tow equipment section](https://openairdocs.org/ntsb-findings/01035301): Aircraft › Aircraft structures · Capability exceeded (probable cause) ## Analysis Shortly after takeoff, the tow airplane pilot felt slack in the tow line and in response he attempted to slow the airplane. He then felt the airplane surge forward and looked back to observe the glider in a sharp turn. The pilot noted his altitude was between 225 to 250 feet above the ground. Witnesses reported that it appeared that the glider released from the tow airplane, and then veered sharply to the right before it entered into a nose dive and impacted the ground. A Federal Aviation Administration airworthiness inspector established flight control continuity of the glider at the accident site. He also noted that the tow line had broken at the weak link. The weak link is a safety line that is designed to release under sudden or extreme loads to protect/ensure that the airframe of the glider is not damaged. The weak link can break at low altitude, causing an inadvertent release. ## Factual narrative HISTORY OF FLIGHT On September 12, 2009, at 1453 Pacific daylight time, a Schweizer SGS 1-34 glider, N7656, impacted the ground in a nose down attitude following a separation of the tow line at the Skylark Field Airport (CA89), Lake Elsinore, California. The pilot/owner operated the glider under the provisions of 14 Code of Federal Regulations (CFR) Part 91, as a personal flight. The pilot, the sole occupant, was killed. The glider sustained substantial damage. Visual meteorological conditions prevailed for the local area flight, and no flight plan had been filed. A Federal Aviation Administration (FAA) airworthiness inspector responded to the site, and interviewed witnesses and the tow airplane pilot. The tow pilot reported that while on the takeoff roll he was manipulating the flight controls due to what he thought was either a crosswind, or the movement of the glider. The tow plane lifted off the ground about 65 miles per hour (mph). He felt what he thought was slack in the tow line and tried to slow down using back pressure. The tow pilot then felt the airplane surge forward as if the tow line had been released. He looked back to confirm that the glider had released and saw it in a sharp right turn and then hit the ground. The tow plane pilot looked back at his altimeter and noted that the tow plane's altitude was between 225 to 250 feet at the time. Ground witnesses reported that from their viewpoint, it appeared that the glider released from the tow airplane, and then veered sharply to the right before it entered into a nose dive prior to impacting the ground. One of the witnesses reported that while still on the ground the glider was pulling towards the right, but before it lifted off the ground it had corrected itself. During the inspection of the glider, the FAA inspector established flight control continuity. The FAA inspector also reported that the tow line broke at a point called the weak link. The FAA inspector indicated that the link was in good condition and showed no signs of wear. PERSONNEL INFORMATION A review of FAA airman records revealed that the 70-year-old pilot held a pilot certificate with ratings for glider aero tow only. The pilot held a third-class medical certificate issued on April 7, 2008. It had the limitations that the pilot must wear corrective lenses. A reissuance of the pilot's private pilot certificate was dated May 21, 2009, and showed his ratings as airplane single engine land and sea, and glider. A corresponding logbook entry revealed that the pilot passed his airplane single engine sea check ride. A review of excerpts of the pilot's logbook by the National Transportation Safety Board investigator-in-charge estimated a total of 192.9 hours of glider time; with 15.6 hours logged between February and August 2009. The pilot's estimated total time was 817.7 hours. MEDICAL AND PATHOLOGICAL INFORMATION The Riverside County Sheriff-Coroner, Riverside, California, completed an autopsy on September 15, 2009. Thecause of death was listed as multiple blunt force trauma. The coroner's report noted that the pilot initially survived the accident, but succumbed to his injuries during surgery. According to the pilot's wife, he had flown gliders for over 30 years, and he was not taking any prescription medication. However, he was blind in his right eye, but did not need to wear corrective lenses. The FAA Forensic Toxicology Research Team, Oklahoma City, Oklahoma, performed toxicological testing of specimens of the pilot. Analysis of the specimens contained no findings for carbon monoxide, cyanide or volatiles. The report contained the following findings for tested drugs: atropine and lidocaine detected in blood and lidocaine detected in urine. ADDITIONAL INFORMATION: The weak link is a safety line that is designed to "break" (release) under sudden or extreme loads to protect/ensure that the airframe of the glider is not damaged. The weak link can break at low altitude, causing an inadvertent release. If the glider pilot or the tow plane pilot are not able to release the tow line via the primary or secondary release mechanisms, the glider pilot can attempt to snap the weak link with a sharp movement of the glider. In the glider flying handbook, under 14 CFR Part 91 section 91.309, the tow rope has a required strength to be within a range of 80 to 200 percent of the maximum certificated weight of the glider. ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Initial climb: Glider tow event](https://openairdocs.org/ntsb-events/510) (defining event) - [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470) ## Aircraft - Registration: [N7656](https://openairdocs.org/deregistered/N7656-2009-10-29), registration cancelled 2009-10-29, S/N 36, built 1970 (OpenAirDocs) - Reported make and model: SCHWEIZER SGS 1-34 - 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: 17274326 - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: William R Klesse - Registered owner: L E S C - Airworthiness certificate: Standard, Normal - Departed: CA89, Lake Elsinore, CA - Destination: CA89, Lake Elsinore, CA - Airport: CA89, Skylark Field Airport, runway 29L, 2,800 × 100 ft, grass/turf ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 70; injuries: fatal; private; airplane ratings: single-engine sea, single-engine land; medical: class 3, with waivers/limitations; seat: center; toxicology performed; flight hours: 830 total, 167 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 310° at 14 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 90 °F, dew point 57 °F - Altimeter: 29.79 inHg - Observed at: RIV, 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 20090912016709A](https://openairdocs.org/incident/20090912016709A), Sep 12, 2009: Scwzer SGS134, Lake Elsinore, CA, Substantial damage, 1 fatal. (-23) Glider on take off crashed on 29R at Skylark airport. Substantial damage. Pilot was transported to hospital and later died. ## Other investigations on N7656 (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 LAX75DUG05](https://openairdocs.org/ntsb/LAX75DUG05), Aug 5, 1974: Schweizer SGS134 (N7656), Helendale, CA, substantial damage ## Docket (3 files) The files NTSB released with the investigation on January 25, 2011, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=74731. 598 KB in all. - Witness Statement (item 1, .PDF, 455 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40340428&FileExtension=.PDF&FileName=Witness%20Statement-Redacted.PDF - Excerpt Glider Logbooks (item 2, .PDF, 102 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40340422&FileExtension=.PDF&FileName=Excerpt%20Glider%20Logbooks-Redacted.PDF - Toxicological Report (item 3, .PDF, 40 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40337274&FileExtension=.PDF&FileName=Toxicological%20Report-Master.PDF 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.