# NTSB ANC12CA111: Robinson Helicopter R22 Beta II, N4171J, Anchorage, AK, September 26, 2012 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: September 25, 2012, 18:00 local (Sep 26, 2012, 02:00 UTC) - Place: Anchorage, AK - Coordinates: 61.208057, -149.84027 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=61.2081&lon=-149.8403&mi=10 - Phase of flight: [Emergency descent](https://openairdocs.org/ntsb-phases/600) (OpenAirDocs' grouping) - Defining event: [Autorotation: Loss of control in flight](https://openairdocs.org/ntsb-events/240) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report December 19, 2012 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - Parties: Federal Aviation Administration - NTSB case key (mKey): 85148 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC12CA111 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/85148/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=85148 - Page: https://openairdocs.org/ntsb/ANC12CA111 ## Probable cause The flight instructor's inadequate supervision of the student pilot during a hovering autorotation, which resulted in a dynamic rollover. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Attention/monitoring: monitoring other person](https://openairdocs.org/ntsb-findings/02021535): Personnel issues › Psychological · Instructor/check pilot (probable cause); cases with it: [Robinson Helicopter R22 BETA, 15 cases](https://openairdocs.org/ntsb-findings/02021535/cases.md?model=7640110), [All aircraft, 200 cases](https://openairdocs.org/ntsb-findings/02021535/cases.md) - [Action: delayed action](https://openairdocs.org/ntsb-findings/02041025): Personnel issues › Action/decision · Instructor/check pilot (probable cause); cases with it: [Robinson Helicopter R22 BETA, 35 cases](https://openairdocs.org/ntsb-findings/02041025/cases.md?model=7640110), [All aircraft, 894 cases](https://openairdocs.org/ntsb-findings/02041025/cases.md) - [Performance/control parameters: directional control](https://openairdocs.org/ntsb-findings/01062020): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Robinson Helicopter R22 BETA, 14 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md?model=7640110), [All aircraft, 3,958 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Autorotation: 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) - [Landing-flare/touchdown: Abnormal runway contact](https://openairdocs.org/ntsb-events/090); cases with it: [Robinson Helicopter R22 BETA, 5 cases](https://openairdocs.org/ntsb-events/090/sequence.md?model=7640110), [All aircraft, 1,506 cases](https://openairdocs.org/ntsb-events/090/sequence.md) - [Landing: Dynamic rollover](https://openairdocs.org/ntsb-events/231); cases with it: [Robinson Helicopter R22 BETA, 35 cases](https://openairdocs.org/ntsb-events/231/sequence.md?model=7640110), [All aircraft, 161 cases](https://openairdocs.org/ntsb-events/231/sequence.md) ## Analysis The flight instructor was providing primary helicopter flight instruction to a student pilot. The instructor reported that while practicing a series of hovering autorotations, he inadvertently allowed the student pilot to drift to the left during the descent. The instructor then took control of the helicopter, applied right cyclic, and raised the collective slightly to level the helicopter and arrest the descent, but the helicopter started to descend with the right skid low. The instructor then added left cyclic and raised the collective further in an attempt to cushion the landing. The helicopter then drifted to the right as the right skid subsequently struck the ground. After touchdown, the helicopter’s skids slid over the asphalt surface before the right skid “caught,” the helicopter rolled to the right, and the main rotor blades struck the ground. The helicopter came to rest on its right side, sustaining substantial damage to the fuselage, tail boom, and main rotor drive system. The instructor reported that there were no preaccident mechanical problems with the helicopter that would have precluded normal operation. He also stated that the accident might have been avoided if he had taken corrective action sooner and with less input on the cyclic. ## Factual narrative The certificated flight instructor (CFI) was providing primary helicopter flight instruction to a student pilot. The CFI reported that while practicing a series of hovering autorotations, he inadvertently allowed the student pilot to drift to the left during the descent. The CFI then took control of the helicopter, applied right cyclic and raised the collective slightly to level the helicopter and arrest the descent, but the helicopter started to descend with the right skid low. He then added left cyclic, and raised the collective further in an attempt to cushion the landing. The helicopter then drifted to the right as the right skid subsequently struck the ground. After touchdown, the helicopter’s skids slid over the asphalt surface before the right skid “caught” and the helicopter rolled to the right, and the main rotor blades struck the ground. The helicopter came to rest on its right side, sustaining substantial damage to the fuselage, tail boom and main rotor drive system. In his written statement to the NTSB, the pilot reported that there were no preaccident mechanical problems with the helicopter, and in the recommendations section of the NTSB 6120.1 form he reported that the accident might have been avoided if he had taken corrective action sooner, and with less input on the cyclic. ## Aircraft - Registration: [N4171J](https://openairdocs.org/aircraft/N4171J), registered now, S/N 4392, built 2008 (OpenAirDocs) - Reported make and model: ROBINSON HELICOPTER R22 BETA II - 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: 4392 - Airframe hours: 2096 - Engines: Lycoming O-360-J2A 124 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Operator: Alpine Air Alaska Inc - Registered owner: Alpine Air Alaska Inc - Airworthiness certificate: Standard, Normal - Last inspection: Annual, September 1, 2012 - Departed: PAMR, Anchorage, AK - Destination: PAMR, Anchorage, AK - Airport: PAMR, Merrill Field, runway 05, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Flight instructor; age 31; injuries: none; flight instructor; instrument ratings: helicopter; medical: class 2, without waivers/limitations; last flight review December 11, 2011; seat: right; flight hours: 338 total, 255 in this make and model, 271 as pilot in command, 127 in the last 90 days, 45 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: 8,500 ft overcast - Temperature: 48 °F, dew point 45 °F - Altimeter: 29.30 inHg - Observed at: PAMR ## 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 20120925023289A](https://openairdocs.org/incident/20120925023289A), Sep 25, 2012: Robinson Helicopter R22 BETA, Anchorage, AK, Substantial damage. R-22 helicopter hover autorotation:the CFI was PIC for the flight with a student in which simulated power failures at a hover (hovering autorotations) were… ## Docket (2 files) The files NTSB released with the investigation on October 29, 2012, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=85148. 973 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 739 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40379222&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Helicopter Supplemental Checklist (item 2, .PDF, 234 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40380115&FileExtension=.PDF&FileName=Helicopter%20Supplemental%20Checklist-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.