# NTSB DEN03LA132: Cessna 172P, N98969, Watkins, CO, July 17, 2003 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 17, 2003, 09:41 local (15:41 UTC) - Place: Watkins, CO - Coordinates: 39.783611, -104.535003 - Nearby events: https://openairdocs.org/map.md?lat=39.7836&lon=-104.5350&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report September 29, 2004 - Report: Approved by Office Director - Parties: Cessna Aircraft Company, FAA FSDO - NTSB case key (mKey): 57508 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN03LA132 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/57508/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=57508 - Page: https://openairdocs.org/ntsb/DEN03LA132 ## Probable cause the right seat shifting aft during the take off roll, rendering aircraft control not possible by the flight instructor. Contributing factors include the inboard seat pin which did not engage fully, the outboard seat pin which was installed incorrectly, the inadequate installation procedures provided by the manufacturer and the parked aircraft on the ramp. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, takeoff - roll/run - fuselage,seat - shifted (cause) - miscellaneous,dowel/pin - not engaged (contributing factor) - miscellaneous,dowel/pin - reversed (contributing factor) - procedure inadequate, manufacturer (contributing factor) - aircraft manuals,procedure information - inadequate (contributing factor) - Loss of control - on ground/water, takeoff - roll/run - aircraft control - not possible, pilot in command(cfi) (contributing factor) - On ground/water collision with object, takeoff - roll/run - object - aircraft parked/standing (contributing factor) ## Analysis On the second touch and go, the flight instructor said she added full throttle and, as the airplane started to rotate, her seat released and slid aft, causing her to lose her grip on the flight controls. The airplane departed the runway to the left, struck the ground, and traveled 785 feet before colliding with the two unoccupied airplanes, located on the ramp causing substantial damage to the accident airplane. Post examination of the seat rails revealed no anomalies. When brought to the full forward position, the inboard seat pin would not engage fully into the seat track. When force was applied, the seat would move aft. According to a Cessna representative, the outboard seat pin was installed on the outboard side of the seat handle and should be installed on the inboard side of the seat handle. An examination of the remaining aircraft systems revealed no anomalies. The Cessna Model 172 Series Service Manual provides only an illustration addressing the installation of the seat pins. There is no textual data available for installation. ## Factual narrative On July 17, 2003, at 0941 mountain daylight time, a Cessna 172P, N98969, was substantially damaged when it struck two parked Cessna 172s, N54955 and N5484K, during takeoff at Front Range Airport (FTG), Watkins, Colorado. The certified flight instructor and her student were not injured. Visual meteorological conditions prevailed. No flight plan had been filed for the local instructional flight being conducted under the provisions of Title 14 CFR Part 91. The flight originated at Centennial Airport (APA), Englewood, Colorado, at 0730. According to the flight instructor after performing "four taxi back takeoffs" at APA the flight proceeded to FTG. On the second touch-and-go landing on runway 26, the flight instructor said she added full throttle and as the airplane started to rotate, her seat released and slid aft, causing her to lose her grip on the flight controls. The airplane departed the runway to the left, struck the ground, and traveled 785 feet across the grass between the A taxiway and the ramp before colliding with the two unoccupied airplanes, located on the ramp. The accident airplane's right wing was crushed down at the wing root and the wing strut was buckled. The outboard edge of the flap and inboard section of the right aileron was wrinkled. N54955's empennage was destroyed. The left wing tip was crushed and the left aileron separated on the outboard edge and was bent up. The left wing flap was crushed. N5484K sustained minor damage to the rudder. Post examination of the seat rails revealed no anomalies. When brought to the full forward position, the inboard seat pin would not engage fully into the seat track. When force was applied, the seat would move aft. According to a Cessna representative, the outboard seat pin was installed on the outboard side of the seat handle and should be installed on the inboard side of the seat handle. An examination of the remaining aircraft systems revealed no anomalies. The flight instructor was asked to explain how she adjusts her seat in the airplane. She replied that on that particular flight, she lifted the seat leaver, moved the seat full forward, released the leaver and rocked the seat to ensure that it was locked in the seat rail. The Cessna Model 172 Series Service Manual provides only an illustration addressing the installation of the seat pins. There is no textual data available for installation. ## Aircraft - Registration: [N98969](https://openairdocs.org/deregistered/N98969-2018-04-24), registration cancelled 2018-04-24, S/N 17276389, built 1985 (OpenAirDocs) - Reported make and model: Cessna 172P - Registry model: [Cessna 172P](https://openairdocs.org/model/cessna-172p) (registry code 2072436) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 17276389 - Airframe hours: 10581.5 - Engines: Lycoming O-320-D2J 160 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Registered owner: Wings of Denver - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, May 23, 2003, 84.5 hours before - Departed: APA, Englewood, CO - Destination: APA, Englewood, CO - Airport: FTG, Front Range, runway 26, 8,000 × 100 ft, concrete ## Flight crew As NTSB recorded them. NTSB leaves out names. - Flight instructor; age 39; injuries: none; airline transport, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; last flight review June 9, 2002; seat: right; flight hours: 3,069 total, 843 in this make and model, 2,090 as pilot in command, 32 in the last 90 days, 13 in the last 30 days, 2 in the last 24 hours - Student pilot; age 54; injuries: none; student; medical: class 3, valid medical--w/ waivers/lim; seat: left; flight hours: 44 total, 28 in this make and model, 40 in the last 90 days, 15 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 290° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 84 °F, dew point 46 °F - Altimeter: 30.26 inHg - Observed at: DEN, 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). - [Accident 20030717016429A](https://openairdocs.org/incident/20030717016429A), Jul 17, 2003: Cessna 172P, Denver, CO, Substantial damage. (-23) On July 17, 2003, susan baker, flight instructor, was giving landing instruction to kathleen emmons at Front Range Airport in a Cessna 172P (N98969). She… ## Docket (5 files) The files NTSB released with the investigation on July 16, 2004, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=57508. 578 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 299 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40423641&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Supplement E (item 2, .PDF, 89 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40214662&FileExtension=.PDF&FileName=Supplement%20E-Master.PDF - Record of Telephone Interviews (item 3, .PDF, 96 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40423642&FileExtension=.PDF&FileName=Record%20of%20Telephone%20Interviews-Redacted.PDF - Seat Installation Diagram - Cessna 172 (item 4, .PDF, 33 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40214665&FileExtension=.PDF&FileName=Seat%20Installation%20Diagram%20-%20Cessna%20172-Master.PDF - Statement of Party Representatives to NTSB Investigation (item 5, .PDF, 62 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40423643&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation-Redacted.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.