# NTSB WPR15LA209: Mooney M 20G, N9152V, Phoenix, AZ, July 10, 2015 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 10, 2015, 09:00 local (16:00 UTC) - Place: Phoenix, AZ - Coordinates: 33.686389, -112.07611 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=33.6864&lon=-112.0761&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing: Fuel related](https://openairdocs.org/ntsb-events/190) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report January 25, 2018 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 91537 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR15LA209 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/91537/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=91537 - Page: https://openairdocs.org/ntsb/WPR15LA209 ## Probable cause The pilots' failure to apply carburetor heat during the approach for landing, which resulted in a total loss of engine power due to carburetor icing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Ice/rain protection system: intake anti-ice, deice](https://openairdocs.org/ntsb-findings/01023020): Aircraft › Aircraft systems · Not used/operated (probable cause); cases with it: [Mooney M-20G, 1 case](https://openairdocs.org/ntsb-findings/01023020/cases.md?model=5870216), [All aircraft, 108 cases](https://openairdocs.org/ntsb-findings/01023020/cases.md) - [Info processing/decision: identification/recognition](https://openairdocs.org/ntsb-findings/02041510): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Mooney M-20G, 1 case](https://openairdocs.org/ntsb-findings/02041510/cases.md?model=5870216), [All aircraft, 559 cases](https://openairdocs.org/ntsb-findings/02041510/cases.md) - [Info processing/decision: identification/recognition](https://openairdocs.org/ntsb-findings/02041510): Personnel issues › Action/decision · Instructor/check pilot (probable cause); cases with it: [Mooney M-20G, 1 case](https://openairdocs.org/ntsb-findings/02041510/cases.md?model=5870216), [All aircraft, 559 cases](https://openairdocs.org/ntsb-findings/02041510/cases.md) - [Temp/humidity/pressure: conducive to carburetor icing](https://openairdocs.org/ntsb-findings/03031030): Environmental issues › Conditions/weather/phenomena · Effect on operation; cases with it: [Mooney M-20G, 1 case](https://openairdocs.org/ntsb-findings/03031030/cases.md?model=5870216), [All aircraft, 435 cases](https://openairdocs.org/ntsb-findings/03031030/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing: Fuel related](https://openairdocs.org/ntsb-events/190) (defining event); cases with it: [Mooney M-20G, 1 case](https://openairdocs.org/ntsb-events/190/sequence.md?model=5870216), [All aircraft, 361 cases](https://openairdocs.org/ntsb-events/190/sequence.md) - [Landing: Landing area undershoot](https://openairdocs.org/ntsb-events/370); cases with it: [Mooney M-20G, 1 case](https://openairdocs.org/ntsb-events/370/sequence.md?model=5870216), [All aircraft, 201 cases](https://openairdocs.org/ntsb-events/370/sequence.md) - [Landing: Hard landing](https://openairdocs.org/ntsb-events/092); cases with it: [Mooney M-20G, 1 case](https://openairdocs.org/ntsb-events/092/sequence.md?model=5870216), [All aircraft, 2,102 cases](https://openairdocs.org/ntsb-events/092/sequence.md) - [Landing: Landing gear collapse](https://openairdocs.org/ntsb-events/094); cases with it: [Mooney M-20G, 1 case](https://openairdocs.org/ntsb-events/094/sequence.md?model=5870216), [All aircraft, 1,787 cases](https://openairdocs.org/ntsb-events/094/sequence.md) ## Analysis The private pilot receiving instruction reported that, abeam the runway threshold on the downwind leg of the traffic pattern, he reduced engine power to idle to conduct a practice 180o power-off landing. The pilot maintained glide speed until about 40 ft above the ground then noticed that the airplane was slightly below the intended glide path. The pilot applied throttle to initiate a go-around; however, the engine sputtered and power did not increase. The pilot executed a forced landing short of the runway; the airplane touched down hard and bounced. The right main and nose landing gear collapsed, and the airplane came to rest to the right of the runway. The flight instructor reported that, upon the pilot's decision to conduct a go-around, he ensured that the throttle, propeller, and mixture were in the correct position, but made no reference to carburetor heat. During a postaccident examination, the engine was started, operated, and shut down normally with no anomalies noted. Data from the engine monitoring system revealed that, shortly before the engine lost power, it was operating at idle power for about 1 1/2 minutes, during which the cylinder exhaust gas temperatures were decreasing. At the end of the 1 1/2 minutes, in the engine rpm increased and the the exhaust gas temperatures showed a small spike, then continued to decrease. The rpm then decreased to zero, and the manifold pressure adjusted to barometric pressure, consistent with a total loss of power. The reported temperature and dew point at the time of the accident were conducive to carburetor icing at glide and cruise power settings. It is likely that the carburetor collected ice during the time the engine was at idle power. When the pilot increased power, the engine responded momentarily, but was unable to continue operation with the restricted airflow through the carburetor. The airplane's pilot operating handbook stated that full carburetor heat should be applied when reducing power for descent or landing. ## Factual narrative On July 10, 2015, about 0900 mountain standard time, a Mooney M20G, N9152V, experienced a partial loss of engine power while on short final to the Phoenix Deer Valley Airport (DVT), Phoenix, Arizona, and subsequently landed short of the runway. The private pilot undergoing instruction and the certified flight instructor (CFI) sustained no injuries; the airplane sustained substantial damage to the right wing. The airplane is registered to a private individual and operated by the private pilot under the provisions of 14 Code of Federal Regulations Part 91 as an instructional flight. Visual meteorological conditions prevailed and no flight plan was filed. The private pilot undergoing instruction reported that when they passed the approach end of the runway on the downwind leg of the traffic pattern, he reduced power to idle to conduct a practice 180o power off landing. The pilot maintained glide speed until about 40 feet above the ground when the pilot observed the airplane was slightly below the intended glide path. The pilot increased power to initiate a go around, however, the engine sputtered and did not increase RPM. The pilot executed a forced landing short of the runway surface; the airplane touched down hard and bounced. When it settled back onto the ground, the right main landing gear and nose landing gear collapsed and the airplane came to rest to the right of the runway surface. The CFI reported that when the private pilot decided to conduct a go around, he looked at the throttle quadrant to confirm that the throttle was full forward and the propeller and mixture levers were also positioned correctly. A postaccident engine run was conducted by a mechanic and inspectors from the Federal Aviation Administration (FAA). The spark plugs were removed and examined; they displayed signatures consistent with a rich running engine. The spark plugs were reinstalled and an undamaged propeller was installed. The engine started without hesitation; after idling temporarily, the RPM was increased and a magneto check was completed with no abnormalities noted. The power was decreased to idle for two minutes to simulate a 180o power off landing. The throttle was abruptly increased to full power; it hesitated for a split second and went to full RPM for a couple minutes. This sequence was conducted twice with no anomalies noted. The engine was shutdown uneventfully. The engine data monitor download showed that shortly before the engine lost power, the engine was at idle for about 1.5 minutes; during which, the cylinder exhaust gas temperatures were decreasing. At the end of the 1.5 minutes, there was an increase in RPM and subsequent small spike in the exhaust gas temperatures before they continued to decrease. In addition, the RPMs continued to zero, and the manifold pressure adjusted to barometric pressure. At the time of the accident, the reported temperature was 29o C and the dew point was 7o C. According to the FAA carburetor icing Special AirworthinessInformation Bulletin, the condition was conducive to carburetor icing at glide and cruise power settings. ## Aircraft - Registration: [N9152V](https://openairdocs.org/deregistered/N9152V-2017-06-16), registration cancelled 2017-06-16, S/N 690012, built 1969 (OpenAirDocs) - Reported make and model: MOONEY M 20G - Registry model: [Mooney M-20G](https://openairdocs.org/model/mooney-m-20g) (registry code 5870216) (OpenAirDocs) - Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 690012 - Year built: 1969 - Airframe hours: 2993 - Engines: LYCOMING O&VO-360 SER 180 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, April 27, 2015, 60 hours before - Departed: DVT, Phoenix, AZ - Destination: DVT, Phoenix, AZ - Airport: DVT, Phoenix Deer Valley Airport, runway 7L, 4,500 × 75 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 18; injuries: none; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 1, with waivers/limitations; last flight review May 25, 2015; seat: left; restraint: lap only; flight hours: 253 total, 140 in this make and model, 150 as pilot in command, 60 in the last 90 days, 35 in the last 30 days, 5 in the last 24 hours - Flight instructor; age 67; injuries: none; flight instructor, commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; last flight review January 15, 2013; seat: right; restraint: lap only; flight hours: 1 total, 1 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 160° at 9 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 84 °F, dew point 45 °F - Altimeter: 29.90 inHg - Observed at: DVT ## 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 20150710012039A](https://openairdocs.org/incident/20150710012039A), Jul 10, 2015: Mooney M-20G, Phoenix, AZ, Substantial damage. On July 10, 2015 at approx. 0845 PST a Mooney M20G, had been on an instructional flight with a CFI and a private pilot being instructed to upgrade to… ## Docket (5 files) The files NTSB released with the investigation on October 30, 2017, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=91537. 3.6 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 3.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40457395&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Record of Email - Certified Flight Instructor Statement (item 2, .PDF, 54 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40457396&FileExtension=.PDF&FileName=Record%20of%20Email%20-%20Certified%20Flight%20Instructor%20Statement-Master.PDF - Record of Email - FAA Regarding Postaccident Engine Run (item 3, .PDF, 62 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40457397&FileExtension=.PDF&FileName=Record%20of%20Email%20-%20FAA%20Regarding%20Postaccident%20Engine%20Run-Master.PDF - Data from the Engine Monitoring System (item 4, .PDF, 260 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40457398&FileExtension=.PDF&FileName=Data%20from%20the%20Engine%20Monitoring%20System-Master.PDF - Record of Conversation - Lycoming Engines (item 5, .PDF, 53 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40457399&FileExtension=.PDF&FileName=Record%20of%20Conversation%20-%20Lycoming%20Engines-Master.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.