# NTSB WPR19LA140: Cessna 172, N8887U, Red Rock, AZ, May 6, 2019 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 3 · Limited · Final report - Date: May 5, 2019, 17:56 local (May 6, 2019, 00:56 UTC) - Place: Red Rock, AZ - Coordinates: 32.538333, -111.423614 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=32.5383&lon=-111.4236&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-descent: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: No injuries - Injuries: 4 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Western Pacific Region - Parties: FAA - NTSB case key (mKey): 99402 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR19LA140 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/99402/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=99402 - Page: https://openairdocs.org/ntsb/WPR19LA140 ## Probable cause A partial loss of engine power for reasons that could not be determined based on the available information. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Not determined](https://openairdocs.org/ntsb-findings/05000000): Not determined › Not determined · Unknown/Not determined (probable cause); cases with it: [Cessna 172F, 5 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md?model=2072414), [All aircraft, 2,247 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-descent: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Cessna 172F, 4 cases](https://openairdocs.org/ntsb-events/342/sequence.md?model=2072414), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) ## Analysis The pilot reported that, while descending in the single-engine airplane toward the destination airport, the engine lost partial power. He performed a forced landing to a dirt road, during which the airplane contacted a bush, resulting in substantial damage. Postaccident examination of the engine and an engine test run revealed no anomalies that would have precluded normal operation. Atmospheric conditions at the time of the accident were not conducive to the development of carburetor icing. The reason for the partial loss of engine power could not be determined based on the available information. ## Factual narrative On May 5, 2019, about 1756 mountain standard time, a Cessna 172F airplane, N8887U, was substantially damaged when it was involved in an accident near Red Rock, Arizona. The commercial pilot and three passengers were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that he canceled flight-following about 15 miles west of his destination. During the descent, the engine rpm dropped from 2,600 rpm to 1,300 rpm once or twice, then dropped to 1,000 rpm and remained there. The pilot reported that he checked the magnetos, verified that the fuel selector was on BOTH, and set the fuel mixture to full rich. The pilot performed a forced landing to a dirt road, during which the left wing clipped a bush, resulting in substantial damage. The pilot mentioned that he did not use carburetor heat, as the humidity was very low; calculated relative humidity for the area of the accident site was 27%. Additionally, the pilot reported no additional anomalies with the airplane that would have precluded normal operation. Review of the Carburetor Icing Probability Chart indicated that conditions were not conducive to carburetor icing. The airplane was equipped with a Continental Motors O-300-D engine, serial number 29754-D-5-0. Maintenance records revealed that about 6 days before the accident, the Nos. 2- and 3-cylinder assemblies were replaced, and the lower forward crankcase through bolt and hardware were replaced. Examination of the engine revealed no anomalies, and the engine operated normally during a subsequent test run to about 2,280 rpm. ## Aircraft - Registration: [N8887U](https://openairdocs.org/deregistered/N8887U-2022-04-02), registration cancelled 2022-04-02, S/N 17252806, built 1965 (OpenAirDocs) - Reported make and model: Cessna 172 (F) - Registry model: [Cessna 172F](https://openairdocs.org/model/cessna-172f) (registry code 2072414) (OpenAirDocs) - Registry engine: [Continental 0-300 series](https://openairdocs.org/engine/continental-0-300-series) (registry code 17022, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 17252806 - Year built: 1965 - Airframe hours: 5279 - Engines: Continental O-300 SER 145 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, May 4, 2018, 266 hours before - Departed: CRQ, Carlsbad, CA - Destination: AVQ, Marana, AZ - Equipment: ADS-B ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 34; injuries: none; commercial; airplane ratings: single-engine land; instrument ratings: helicopter; medical: class 2, without waivers/limitations; last flight review April 18, 2019; seat: left; restraint: 3-point; flight hours: 2,000 total, 90 in this make and model, 1,260 as pilot in command, 75 in the last 90 days, 35 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 250° at 10 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 90 °F, dew point 16 °F - Altimeter: 29.70 inHg - Observed at: KMZJ, 13 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 20190505015819A](https://openairdocs.org/incident/20190505015819A), May 5, 2019: Cessna 172F, Red Rock, AZ, Substantial damage. On may 5th, 2019, N8887U lost engine power while on a flight from carlsbad, CA (crq) to marana, AZ (avq). The pilot made a forced landing on a narrow rural… ## Docket (4 files) The files NTSB released with the investigation on January 25, 2022, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=99402. 16.7 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 9 pages, 3.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13037308&FileExtension=pdf&FileName=Pilot%20accident%20report%20form_Redacted-Rel.pdf - Record of phone conversation (pilot) (item 2, PDF, 1 page, 90 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13036714&FileExtension=pdf&FileName=Record%20of%20telephone%20conversation%20with%20pilot-Rel.pdf - Summary of engine examination (item 3, PDF, 7 pages, 2.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13041553&FileExtension=pdf&FileName=Summary%20of%20Engine%20Examination_Redacted-Rel.pdf - Excerpt from FAA pilot operating handbook - carburetor icing probability (item 4, PDF, 4 pages, 10.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13037288&FileExtension=pdf&FileName=Excerpt%20from%20FAA%20Pilot%20Operating%20Handbook%20-%20carburetor%20icing%20propability-Rel.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.