# NTSB WPR12LA140: Robinson Helicopter R22 Beta, N290SH, Palo Alto, CA, March 15, 2012 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: March 15, 2012, 16:45 local (23:45 UTC) - Place: Palo Alto, CA - Coordinates: 37.460277, -122.108612 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=37.4603&lon=-122.1086&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Defining event: [Approach-VFR pattern downwind: Loss of control in flight](https://openairdocs.org/ntsb-events/240) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report February 3, 2014 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration, Robinson Helicopter Company - SAIBs cited in the narratives: [SAIB CE-09-35](https://openairdocs.org/saib/CE-09-35) (OpenAirDocs) - NTSB case key (mKey): 83153 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR12LA140 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/83153/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=83153 - Page: https://openairdocs.org/ntsb/WPR12LA140 ## Probable cause The pilot's improper use of the throttle grip, which resulted in the deactivation of the rpm governor and a loss of rotor rpm. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: prop/rotor parameters](https://openairdocs.org/ntsb-findings/01062052): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Robinson Helicopter R22 BETA, 37 cases](https://openairdocs.org/ntsb-findings/01062052/cases.md?model=7640110), [All aircraft, 182 cases](https://openairdocs.org/ntsb-findings/01062052/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Robinson Helicopter R22 BETA, 96 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=7640110), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Approach-VFR pattern downwind: Loss of control in flight](https://openairdocs.org/ntsb-events/240) (defining event); cases with it: [Robinson Helicopter R22 BETA, 67 cases](https://openairdocs.org/ntsb-events/240/sequence.md?model=7640110), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) - [Autorotation: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Robinson Helicopter R22 BETA, 23 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=7640110), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Landing-flare/touchdown: Roll over](https://openairdocs.org/ntsb-events/097); cases with it: [Robinson Helicopter R22 BETA, 21 cases](https://openairdocs.org/ntsb-events/097/sequence.md?model=7640110), [All aircraft, 261 cases](https://openairdocs.org/ntsb-events/097/sequence.md) ## Analysis During a solo instructional flight, the pilot reported that while on the downwind leg of the traffic pattern, just before turning to the base leg, the helicopter sustained a loss of rotor rpm. The pilot reported that he entered an autorotation and that the throttle was unresponsive. After landing in a marsh area, the helicopter rolled over. A postaccident examination of the helicopter and a successful engine run revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. The pilot's flight instructor related that the pilot had a documented history of inadvertently gripping the throttle on the collective which, while manipulating the collective, would result in overriding the governor and a low rotor condition. ## Factual narrative On March 15, 2012, about 1645 Pacific daylight time (PDT), a Robinson helicopter R22 Beta, N290SH, made a hard landing at the Palo Alto Airport, Palo Alto, California, following a loss of engine power. The helicopter was registered to Parker Helicopter LLC, and operated by Sirius Flying, LLC, under the provisions of 14 Code of Federal Regulations (CFR) Part 91. The pilot received a minor injury; the helicopter sustained substantial damage. The local instructional flight departed Palo Alto at 1640 PDT. Visual meteorological conditions prevailed, and no flight plan had been filed.The operator reported that the pilot stated that while on downwind, just prior to turning base, the helicopter experienced a loss of main rotor rpm. The pilot entered an autorotation and noticed that the throttle was unresponsive. During the forced landing into a marsh area, the helicopter rolled over. The pilot, with the assistance of legal counsel, submitted a Pilot/Operator Aircraft Accident Report (NTSB Form 6120.1/2). The pilot stated that the helicopter and engine had no mechanical failures or malfunctions during the flight until the low rotor horn activated and the engine became unresponsive. The pilot's statement indicated that she had followed all of the procedures in the helicopter pilot operating handbook and utilized the proper checklists for the pre-flight and takeoff. PERSONNEL INFORMATION A review of Federal Aviation Administration (FAA) airman records revealed that the 50-year-old pilot held a commercial pilot certificate with ratings for airplane single-engine land, glider, and instrument airplane. She held a certified flight instructor (CFI) certificate with ratings for airplane single-engine land, and instrument airplane. She was operating the helicopter under a student pilot certificate. The pilot held a third-class medical certificate issued on March 21, 2011. It had the limitations that the pilot must wear corrective lenses. The pilot reported that she had accumulated a total helicopter time of 46 hours with 8 hours as pilot-in-command. Total time in all aircraft was reported as 750 hours. METEOROLOGICAL INFORMATION Weather at the time of the accident at 1647, was wind 270 at 10 knots; temperature 63 degrees Fahrenheit; dew point 55 degrees Fahrenheit. The carburetor icing probability chart from Federal Aviation Administration (FAA) Special Airworthiness Information Bulletin (SAIB): CE-09-35 Carburetor Icing Prevention, June 30, 2009, shows a probability of serious icing at glide power at the temperature and dew point reported at the time of the accident. TESTS AND RESEARCH Investigators examined the wreckage at Plain Parts, Sacramento, California, on April 25, 2012. The engine was started and run at idle until warm then run up to 100 percent. The magnetos were tested, and the right magneto had an excessive rpm drop. The left magneto was good. The engine was shut down, and the bottom spark plug from the number 4 cylinder was removed and cleaned andinstalled in number 3 cylinder bottom position. The number 3 bottom spark plug was moved to the number 4 bottom position. The engine was restarted and ran to 100 percent, and both magnetos tests were within limits. The postaccident examination of the helicopter and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. The pilot's instructor related that she had a history of inadvertently gripping the throttle on the collective which, while manipulating the collective, would result in overriding the governor and a low rotor condition. When this would happen the instructor would have to intervene to correct the low rotor condition. The instructor related that he thought the pilot had learned to correct the low rotor condition if it were to occur. On March 26, 2012, FAA inspectors from the San Jose Flight Standards District Office, met with the pilot and her attorney to discuss the accident. The pilot stated she was unable to furnish any information about the accident due to the event being too traumatic to recall. The attorney stated he had written the statement that the pilot submitted to the NTSB. ## Aircraft - Registration: [N290SH](https://openairdocs.org/aircraft/N290SH), registered now, S/N 4186, built 2007 (OpenAirDocs) - Reported make and model: ROBINSON HELICOPTER R22 BETA - Registry model: [Robinson Helicopter R22 BETA](https://openairdocs.org/model/robinson-helicopter-r22-beta) (registry code 7640110) (OpenAirDocs) - Registry engine: [Lycoming O-360-J2A](https://openairdocs.org/engine/lycoming-o-360-j2a) (registry code 42314, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: 4186 - Airframe hours: 2051 - Engines: LYCOMING O-360-J2A 145 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Operator: Sirius Flying LLC - Registered owner: Parker Helicopter LLC - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, February 10, 2012, 63 hours before - Departed: PAO, Palo Alto, CA - Destination: PAO, Palo Alto, CA - Airport: PAO, Palo Alto Airport, runway 31, 2,443 × 70 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 50; injuries: minor; flight instructor, commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; last flight review January 12, 2012; seat: right; flight hours: 750 total, 46 in this make and model, 631 as pilot in command, 24 in the last 90 days, 7 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 270° at 10 knots - Visibility: 13 statute miles - Lowest ceiling: 2,500 ft broken - Temperature: 63 °F, dew point 55 °F - Altimeter: 30.10 inHg - Observed at: PAO ## 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 20120315004889A](https://openairdocs.org/incident/20120315004889A), Mar 15, 2012: Robinson Helicopter R22 BETA, Palo Alto, CA, Substantial damage. During an approach for landing at Palo Alto airport, runway 31, the pilot was cleared by ATCT for the option on runway 31. Directly after receiving clearance… ## Docket (7 files) The files NTSB released with the investigation on November 7, 2013, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=83153. 3.2 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1- Operator (item 1, .PDF, 390 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40403695&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-%20Operator-Redacted.PDF - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1- Pilot (item 2, .PDF, 540 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40394907&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-%20Pilot-Redacted.PDF - Statement of CFI- Pyle (item 3, .PDF, 24 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40394908&FileExtension=.PDF&FileName=Statement%20of%20CFI-%20Pyle-Master.PDF - Examination Report (item 4, .PDF, 10 photos, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40394909&FileExtension=.PDF&FileName=Examination%20Report-Master.PDF - FAA Interview of Pilot (item 5, .PDF, 214 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40394910&FileExtension=.PDF&FileName=FAA%20Interview%20of%20Pilot-Redacted.PDF - Statement of Party Representatives to NTSB Investigation (item 6, .PDF, 719 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40394911&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation-Redacted.PDF - Release of Aircraft Wreckage, NTSB Form 6120.15 (item 7, .PDF, 134 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40394912&FileExtension=.PDF&FileName=Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15-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.