# NTSB WPR12CA084: Schweizer SGS 2-33A, N17873, Peoria, AZ, January 28, 2012 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Data collection · Final report - Date: January 28, 2012, 10:15 local (17:15 UTC) - Place: Peoria, AZ - Coordinates: 33.792778, -112.265274 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=33.7928&lon=-112.2653&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-climb to cruise: Glider tow event](https://openairdocs.org/ntsb-events/510) - Highest injury: Minor injuries - Injuries: 2 minor - Status: Completed, report April 2, 2012 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 82771 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR12CA084 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/82771/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=82771 - Page: https://openairdocs.org/ntsb/WPR12CA084 ## Probable cause The glider pilot released from the tow airplane at a lower altitude than the planned altitude, which resulted in an off-airport landing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Action: incorrect action sequence](https://openairdocs.org/ntsb-findings/02041020): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Schweizer SGS 2-33A, 1 case](https://openairdocs.org/ntsb-findings/02041020/cases.md?model=8051606), [All aircraft, 77 cases](https://openairdocs.org/ntsb-findings/02041020/cases.md) - [Performance/control parameters: altitude](https://openairdocs.org/ntsb-findings/01062012): Aircraft › Aircraft oper/perf/capability · Incorrect use/operation (probable cause); cases with it: [Schweizer SGS 2-33A, 6 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md?model=8051606), [All aircraft, 1,310 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-climb to cruise: Glider tow event](https://openairdocs.org/ntsb-events/510) (defining event); cases with it: [Schweizer SGS 2-33A, 4 cases](https://openairdocs.org/ntsb-events/510/sequence.md?model=8051606), [All aircraft, 45 cases](https://openairdocs.org/ntsb-events/510/sequence.md) - [Landing: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Schweizer SGS 2-33A, 8 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=8051606), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Landing-flare/touchdown: Hard landing](https://openairdocs.org/ntsb-events/092); cases with it: [Schweizer SGS 2-33A, 6 cases](https://openairdocs.org/ntsb-events/092/sequence.md?model=8051606), [All aircraft, 2,102 cases](https://openairdocs.org/ntsb-events/092/sequence.md) ## Analysis The glider pilot stated that he set the altimeter to the field elevation of 1,600 feet mean sea level (msl) before takeoff. He planned to have the glider towed to 4,000 feet above ground level (agl), which would be 5,600 feet msl, then to release the tow line. During the tow, the pilot released from the tow plane when the altimeter read 4,000 feet (which was 2,400 feet agl). During the return glide back to the airport in a headwind, he realized he was too low to make it to the airport and executed a landing 2 miles short of the runway into desert terrain. On final approach for landing, the pilot maneuvered the glider to avoid a canal. The glider landed hard, and the fuselage sustained substantial damage. The pilot stated that he mistakenly released from the tow at 4,000 feet msl, when he should have released at 4,000 feet agl. He also stated that the glider had no mechanical failures or malfunctions during the flight. ## Factual narrative The glider pilot stated that he set the altimeter to the field elevation of 1,600 feet mean sea level (msl) before takeoff. He planned on having the glider towed to 4,000 feet above ground level (agl), which would be 5,600 feet msl, then release the tow line. During the tow, the pilot released from the tow plane when the altimeter read 4,000 feet. During the return glide back to the airport in a headwind he realized he was too low to make it to the airport and executed a forced landing 2 miles short of the runway into desert terrain. The pilot stated that he mistakenly released from the tow at 4,000 feet msl, when he should have released at 4,000 feet agl. He also stated that the glider had no mechanical failures or malfunctions during the flight. ## Aircraft - Registration: [N17873](https://openairdocs.org/aircraft/N17873), registered now, S/N 243 (OpenAirDocs) - Reported make and model: SCHWEIZER SGS 2-33A - Registry model: [Schweizer SGS 2-33A](https://openairdocs.org/model/schweizer-sgs-2-33a) (registry code 8051606) (OpenAirDocs) - Registry engine: [NONE](https://openairdocs.org/engine/none) (registry code 00000, none) (OpenAirDocs) - Category: Glider - Serial number: 243 - Airframe hours: 2217 - Damage: Substantial damage - Flight: Instructional, Part 91 - Operator: Pleasant Valley Soaring LLC - Registered owner: Pleasant Valley Soaring LLC - Airworthiness certificate: Standard, Normal - Last inspection: Annual, September 2, 2011 - Departed: KP48, Peoria, AZ - Destination: KP48, Peoria, AZ - Flight plan: Unknown - Airport: KP$*, Pleasant Valley Airport ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 72; flight instructor, commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, with waivers/limitations; last flight review April 22, 2011; seat: rear; flight hours: 11,658 total, 151 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 350° at 8 knots - Temperature: 63 °F, dew point 3 °F - Altimeter: 30.20 inHg - Observed at: KDVT, 12 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 20120128000729A](https://openairdocs.org/incident/20120128000729A), Jan 28, 2012: Schweizer SGS 2-33A, Substantial damage. Pilot, [privacy data omitted], reported that he took a passenger for a glider ride. He said the normal altitude they release from the tow plane is at… ## Docket (3 files) The files NTSB released with the investigation on March 2, 2012, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=82771. 4.2 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 1.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40363899&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Photo 1 - On scene photo (item 2, .PDF, 1.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40363900&FileExtension=.PDF&FileName=Photo%201%20-%20On%20scene%20photo-Master.PDF - Photo 2 - Fuselage damage (item 3, .PDF, 1.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40363903&FileExtension=.PDF&FileName=Photo%202%20-%20Fuselage%20damage-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.