# NTSB DEN05LA093: Cessna 172N, N733RL, Hudson, CO, June 19, 2005 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: June 19, 2005, 12:55 local (18:55 UTC) - Place: Hudson, CO - Coordinates: 40.099998, -104.701667 - Nearby events: https://openairdocs.org/map.md?lat=40.1000&lon=-104.7017&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report December 20, 2005 - Report: Approved by Office Director - Parties: FAA Flight Standards District Office - NTSB case key (mKey): 61807 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN05LA093 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/61807/pdf - Page: https://openairdocs.org/ntsb/DEN05LA093 ## Probable cause The flight instructor's improper use raising of the flaps. Contributing factors were the student pilot's misunderstanding of the instructor's intentions, the instructor's inadequate supervision of the student pilot, the density altitude, and the soft terrain. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Abrupt maneuver, takeoff - initial climb - instructions,written/verbal - not understood, dual student (contributing factor) - weather condition - high density altitude (contributing factor) - raising of flaps - improper, pilot in command(cfi) (cause) - flt control syst,wing flap control - activated (cause) - supervision - inadequate, pilot in command(cfi) (contributing factor) - In flight collision with terrain/water, descent - uncontrolled - terrain condition - soft (contributing factor) ## Analysis The flight instructor and his private pilot student were practicing touch and go landings. The student did not turn the carburetor heat off or put up the flaps after his touch and go, so the instuctor took control of the airplane. He turned off the carburetor heat and he said he got "hasty" and retracted the flaps completely instead of in gradual increments. The aircraft experienced a loss of lift and touched down on soft ground and nosed over. The temperature at the time of the accident was 92 degrees Fahrenheit with a calculated density altitude of 7713 feet msl. ## Factual narrative On June 19, 2005, at 1255 mountain daylight time, a Cessna 172N, N733RL, piloted by a student pilot and under the supervision of a commercial certificated flight instructor, was substantially damaged when it nosed over while performing a touch-and-go landing at Platte Valley Airport (18V), Hudson, Colorado. Visual meteorological conditions prevailed at the time of the accident. The local instructional flight was being conducted under Title 14 CFR Part 91 without a flight plan. The instructor and student pilot reported no injuries. The flight originated at Boulder Municipal Airport (1V5), Boulder, Colorado, at 1210. According to the instructor, the student was asked to perform a touch-and-go landing. After touching down on the runway, the student did not add power because he thought he was making a full-stop landing. The instructor asked if the student was going to take off. The student then added full power and the airplane lifted off. The instructor did not feel that the airplane was climbing at the proper rate, so he took control. He closed the carburetor heat control and noticed the flaps were still extended. He said he got "hasty" and retracted the flaps completely instead of in gradual increments. The airplane settled, touched down on soft ground and nosed over. The vertical stabilizer was crushed, the nose landing gear was broken off, the propeller was bent, and the firewall was buckled. The temperature at the time of the accident was 92 degrees F. Density altitude was calculated to be 7,713 feet msl. ## Aircraft - Registration: [N733RL](https://openairdocs.org/deregistered/N733RL-2006-09-15), registration cancelled 2006-09-15, S/N 17268489, built 1976 (OpenAirDocs) - Reported make and model: Cessna 172N - Registry model: [Cessna 172N](https://openairdocs.org/model/cessna-172n) (registry code 2072434) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 17268485 - Airframe hours: 10747 - Engines: Lycoming O-320-H2AD 160 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Operator: Aviation Services, doing business as Flight School - Registered owner: Lawence W Jones - Airworthiness certificate: Standard, Utility; Standard, Normal - Last inspection: 100 hour, April 1, 2005 - Departed: 18V, Hudson, CO - Destination: 1V5, Boulder, CO - Airport: 18V, Platte Valley Airport, runway 15, 4,100 × 50 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Flight instructor; age 64; injuries: none; flight instructor, commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, with waivers/limitations; last flight review July 1, 2004; seat: right; flight hours: 8,000 total, 400 in this make and model, 7,800 as pilot in command, 90 in the last 90 days, 30 in the last 30 days, 2 in the last 24 hours - Student pilot; injuries: none; private; airplane ratings: single-engine land; instrument ratings: airplane; seat: left ## Weather - Conditions: Visual (VMC), Day - Wind: 360° at 7 knots - Visibility: 20 statute miles - Lowest ceiling: none - Temperature: 91 °F, dew point 46 °F - Altimeter: 30.10 inHg ## 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 20050619016479A](https://openairdocs.org/incident/20050619016479A), Jun 19, 2005: Cessna 172N, Hudson, CO, Destroyed. (-23) Apparently, during the briefing by the instructor on approach, the pilot thought he was to make a full stop landing but the instructor had intended for… 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.