# NTSB DEN08CA157: Schweizer SGS 2-33A, N17939, Boulder, CO, September 9, 2008 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: September 9, 2008, 11:00 local (17:00 UTC) - Place: Boulder, CO - Coordinates: 40.039165, -105.225555 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=40.0392&lon=-105.2256&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-landing roll: Collision during takeoff/land](https://openairdocs.org/ntsb-events/490) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report January 22, 2009 - Report: Approved by Office Director - Parties: FAA Flight Standards District Office - NTSB case key (mKey): 68970 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN08CA157 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/68970/pdf - Page: https://openairdocs.org/ntsb/DEN08CA157 ## Probable cause The pilot's failure to use the dive brake during landing resulting in a long landing and collision. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: descent rate](https://openairdocs.org/ntsb-findings/01062037): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Schweizer SGS 2-33A, 1 case](https://openairdocs.org/ntsb-findings/01062037/cases.md?model=8051606), [All aircraft, 242 cases](https://openairdocs.org/ntsb-findings/01062037/cases.md) - [Action: incorrect action performance](https://openairdocs.org/ntsb-findings/02041015): Personnel issues › Action/decision · Student/instructed pilot (probable cause); cases with it: [Schweizer SGS 2-33A, 4 cases](https://openairdocs.org/ntsb-findings/02041015/cases.md?model=8051606), [All aircraft, 1,386 cases](https://openairdocs.org/ntsb-findings/02041015/cases.md) - [Terrain](https://openairdocs.org/ntsb-findings/03021000): Environmental issues › Physical environment · Contributed to outcome; cases with it: [Schweizer SGS 2-33A, 1 case](https://openairdocs.org/ntsb-findings/03021000/cases.md?model=8051606), [All aircraft, 267 cases](https://openairdocs.org/ntsb-findings/03021000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing-landing roll: Collision during takeoff/land](https://openairdocs.org/ntsb-events/490) (defining event); cases with it: [Schweizer SGS 2-33A, 7 cases](https://openairdocs.org/ntsb-events/490/sequence.md?model=8051606), [All aircraft, 1,309 cases](https://openairdocs.org/ntsb-events/490/sequence.md) ## Analysis According to the pilot, he was conducting his fourth solo flight and during the aero tow he "ballooned" and drifted to the right. The pilot repositioned the glider, slack developed in the tow rope, and the rope disconnected from the glider approximately 10 feet above the ground. The pilot did not use the dive brake to descend and landed long, resulting in substantial damage. An examination of the glider systems, conducted by the FAA, revealed no anomalies. ## Factual narrative According to the pilot, he was conducting his fourth solo flight and during the aero tow he "ballooned" and drifted to the right. The pilot repositioned the glider, slack developed in the tow rope, and the rope disconnected from the glider approximately 10 feet above the ground. The pilot did not use the dive brake to descend and landed long, resulting in substantial damage. An examination of the glider systems, conducted by the FAA, revealed no anomalies. ## Aircraft - Registration: [N17939](https://openairdocs.org/aircraft/N17939), registered now, S/N 294, built 1973 (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) - Category: Glider - Serial number: 294 - Damage: Substantial damage - Flight: Instructional, Part 91 - Operator: Mile High Gliding Inc - Registered owner: Mile High Gliding Inc - Airworthiness certificate: Standard, Normal - Departed: KBDU, Boulder, CO - Destination: KBDU, Boulder, CO - Airport: KBDU, Boulder Municipal Airport, runway 08, 4,100 × 75 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Student pilot; age 49; injuries: none; private; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; last flight review March 18, 2008; seat: front; flight hours: 890 total, 5 in this make and model, 791 as pilot in command, 95 in the last 90 days, 30 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 57 °F, dew point 46 °F - Altimeter: 30.04 inHg - Observed at: BJC, 10 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). - [Incident 20080909849879I](https://openairdocs.org/incident/20080909849879I), Sep 9, 2008: Scwzer SGS233A, Boulder, CO, Minor damage. (-23) Pilot was on third solo flight on 09/09/2008 and on aerotow glider towhook auto released. Pilot did not use dive brake for immediate descent and landed… 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.