# NTSB DEN05LA013: Cessna 170A, N9176A, Glenwood Spring, CO, October 23, 2004 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: October 23, 2004, 11:05 local (17:05 UTC) - Place: Glenwood Spring, CO - Coordinates: 39.515556, -107.686668 - Nearby events: https://openairdocs.org/map.md?lat=39.5156&lon=-107.6867&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed, report March 30, 2005 - Report: Approved by Office Director - Parties: FAA Flight Standards District Office, Teledyne Continental Motors, Inc., Cessna Aircraft Company - NTSB case key (mKey): 60429 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN05LA013 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/60429/pdf - Page: https://openairdocs.org/ntsb/DEN05LA013 ## Probable cause the pilot's failure to use carburetor heat which resulted in the formation of carburetor ice and the loss of engine power. Related factors were conditions conducive for carburetor icing and the lack of suitable terrain for a forced landing. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(partial) - nonmechanical, approach - vfr pattern - final approach - carburetor heat - not used, pilot in command (cause) - fuel system,carburetor - ice (cause) - weather condition - carburetor icing conditions (contributing factor) - Forced landing, descent - emergency - In flight collision with object, emergency descent/landing - object - residence - terrain condition - none suitable (contributing factor) - In flight collision with terrain/water, descent - uncontrolled - terrain condition - ground ## Analysis Prior to the accident, the pilot had been flying for approximately 1 hour. He stated that he descended from approximately 8,500 feet msl at an engine power setting of 2,200 rpm, without carburetor heat. This descent lasted approximately 20 to 30 minutes as he flew from west to east, approximately 60 miles. The pilot entered the traffic pattern at approximately 7,000 feet msl. He applied carburetor heat, enrichened the mixture "somewhat", and reduced power to approximately 1,500 to 1,700 rpm, "prepatory for landing." The aviation routine weather report (METAR) reported the temperature as 34 degrees Fahrenheit (F) and the dewpoint as 31 degrees F. According to the carburetor icing chart, conditions were conducive for "serious icing at cruise power."According to the pilot, he was on final approach when he "decided [the] aircraft [was] too high" and added throttle to initiate a go-around. The engine did not respond to the application of throttle. The airplane impacted the roof of a townhouse, slid down and subsequently impacted the side of an adjacent townhouse causing substantial damage to the airplane. ## Factual narrative On October 23, 2004, at approximately 1105 mountain daylight time, a Cessna 170A, N9176A, piloted by a private pilot, was substantially damaged when it impacted the roof of a townhouse while maneuvering near Glenwood Springs, Colorado. Visual meteorological conditions prevailed at the time of the accident. The personal flight was being conducted under the provisions of Title 14 CFR Part 91 without a flight plan. The pilot sustained serious injuries. The local flight originated at approximately 1000. Prior to the accident, the pilot had been flying for approximately 1 hour. He stated that he descended from approximately 8,500 feet msl at an engine power setting of 2,200 rpm, without carburetor heat. This descent lasted approximately 20 to 30 minutes as he flew from west to east, approximately 60 miles. The pilot entered the traffic pattern at approximately 7,000 feet msl. He applied carburetor heat, enrichened the mixture "somewhat," and reduced power to approximately 1,500 to 1,700 rpm, "prepatory for landing." According to the accident report submitted by the pilot, he was on final approach for runway 32 when he "decided [the] aircraft [was] too high" and added throttle to initiate a go-around. The engine did not respond to the application of throttle. In a phone conversation with the pilot, he stated that the engine did not cough or sputter and the propeller was still spinning. According to a witness who observed the airplane prior to the accident, the engine sounded as if it was running with "landing power." The pilot reversed course to avoid flying over the city of Glenwood Springs. He was unable to maintain altitude and the airplane impacted the roof of a townhouse, slid down the roof and subsequently impacted the side of an adjacent townhouse. The airplane came to rest on the ground between the two town homes. The engine, propeller and cowling were crushed aft and the left wing was crushed aft. On November 4, 2004, the engine was inspected and run by a representative of Teledyne Continental Motors under the auspices of the National Transportation Safety Board. No anomalies were noted that would have precluded the engine from producing power. The aviation routine weather report (METAR) at Rifle, Colorado, reported the temperature as 34 degrees Fahrenheit (F) and the dewpoint as 31 degrees F. According to the carburetor icing chart, conditions were conducive for "serious icing at cruise power." ## Aircraft - Registration: [N9176A](https://openairdocs.org/deregistered/N9176A-2018-01-29), registration cancelled 2018-01-29, S/N 18937, built 1949 (OpenAirDocs) - Reported make and model: Cessna 170A - Registry model: [Cessna 170A](https://openairdocs.org/model/cessna-170a) (registry code 2072304) (OpenAirDocs) - Registry engine: [Continental C145 series](https://openairdocs.org/engine/continental-c145-series) (registry code 17012, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 18937 - Airframe hours: 3896 - Engines: Teledyne Continental C-145-2 145 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, January 12, 2004, 41 hours before - Departed: GWS, Glenwood Spring, CO - Airport: GWS, Glenwood Springs Muni ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 69; injuries: serious; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; last flight review August 19, 2004; seat: left; flight hours: 624 total, 215 in this make and model, 21 in the last 90 days, 12 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: 34 °F, dew point 30 °F - Altimeter: 30.12 inHg - Observed at: RIL, 19 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 20041023026839A](https://openairdocs.org/incident/20041023026839A), Oct 23, 2004: Cessna 170A, Glenwood Sprin, CO, Destroyed. (-23) The pilot reported he was in the normal pattern for runway 32 at Glenwood springs when he decided he was too high and elected to go-around and make… 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.