# NTSB WPR09CA375: Robinson Helicopter R22 Beta, N7176W, Troutdale, OR, July 29, 2009

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Data collection · Final report
- Date: July 29, 2009, 11:00 local (18:00 UTC)
- Place: Troutdale, OR
- Coordinates: 45.520244, -122.350593 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=45.5202&lon=-122.3506&mi=10
- Phase of flight: [Emergency descent](https://openairdocs.org/ntsb-phases/600) (OpenAirDocs' grouping)
- Defining event: [Autorotation: Hard landing](https://openairdocs.org/ntsb-events/092)
- Highest injury: Minor injuries
- Injuries: 2 minor
- Status: Completed, report September 30, 2009
- Report: Approved by Office Director
- NTSB office: Western Pacific Region
- Parties: Federal Aviation Administration
- NTSB case key (mKey): 74398
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR09CA375
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/74398/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=74398
- Page: https://openairdocs.org/ntsb/WPR09CA375

## Probable cause

The flight instructor's failure to maintain adequate main 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.

- [Autorotation: Hard landing](https://openairdocs.org/ntsb-events/092) (defining event); cases with it: [Robinson Helicopter R22 BETA, 54 cases](https://openairdocs.org/ntsb-events/092/sequence.md?model=7640110), [All aircraft, 2,102 cases](https://openairdocs.org/ntsb-events/092/sequence.md)

## Analysis

After practicing a series of autorotations, the flight instructor and his student attempted to complete a 180-degree autorotation. The student began a stabilized autorotation from the downwind leg of the traffic pattern. According to the flight instructor, during the turn the student allowed the nose of the helicopter to drop; he was instructed to correct this attitude by applying aft cyclic. When the student completed the turn at an altitude of 200 to 250 ft agl and at a speed of 80 to 85 knots, the flight instructor believed that the outcome of the maneuver was in doubt. The flight instructor then took control of the helicopter and began to initiate a recovery by raising the nose and attempting to increase the throttle and collective to arrest the descent rate. According to the flight instructor, the RPM decayed and the low rotor rpm horn came on at 150 to 100 ft agl. The helicopter landed hard and subsequently slid off the north side of the taxiway. The forward section of the left skid contacted the soft dirt, which resulted in the helicopter turning to the left and nosing over. Examination of the aircraft by a Federal Aviation Administration inspector revealed substantial damage to the helicopter consisted of the separation of the tail boom assembly, damage to the firewall, the left forward frame, and left skid support structure. The flight instructor reported no mechanical anomalies with the helicopter or flight control systems.

## Factual narrative

After practicing a series of autorotations, the flight instructor and his student attempted to complete a 180-degree autorotation. The student began a stabilized autorotation from the downwind leg of the traffic pattern. According to the flight instructor, during the turn the student allowed the nose of the helicopter to drop; he was instructed to correct this attitude by applying aft cyclic. When the student completed the turn at an altitude of 200 to 250 ft agl and at a speed of 80 to 85 knots, the flight instructor believed that the outcome of the maneuver was in doubt. The flight instructor then took control of the helicopter and began to initiate a recovery by raising the nose and attempting to increase the throttle and collective to arrest the descent rate. According to the flight instructor, the RPM decayed and the low rotor rpm horn came on at 150 to 100 ft agl. The helicopter landed hard and subsequently slid off the north side of the taxiway. The forward section of the left skid contacted the soft dirt, which resulted in the helicopter turning to the left and nosing over. Examination of the aircraft by a Federal Aviation Administration inspector revealed substantial damage to the helicopter consisted of the separation of the tail boom assembly, damage to the firewall, the left forward frame, and left skid support structure. The flight instructor reported no mechanical anomalies with the helicopter or flight control systems.

## Aircraft

- Registration: [N7176W](https://openairdocs.org/deregistered/N7176W-2009-12-09), registration cancelled 2009-12-09, S/N 2735, built 1997 (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 0-360-A1D](https://openairdocs.org/engine/lycoming-0-360-a1d) (registry code 41504, reciprocating) (OpenAirDocs)
- Category: Helicopter
- Serial number: 2735
- Airframe hours: 6135
- Engines: LYCOMING O-360-A1D 180 horsepower reciprocating
- Damage: Substantial damage
- Flight: Instructional, Part 91
- Operator: Hillsboro Aviation Inc
- Registered owner: Hillsboro Aviation Inc
- Airworthiness certificate: Standard, Normal
- Last inspection: 100 hour, July 2, 2009, 99 hours before
- Departed: KTTD, Troutdale, OR
- Destination: KTTD, Troutdale, OR
- Airport: KTTD, Portland-Troutdale, runway 25, 5,399 × 150 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Flight instructor; age 24; injuries: minor; commercial, flight instructor; instrument ratings: helicopter; medical: class 1, without waivers/limitations; last flight review March 16, 2009; seat: left; flight hours: 1,130 total, 1,116 in this make and model, 1,040 as pilot in command, 192 in the last 90 days, 99 in the last 30 days, 0 in the last 24 hours
- Student pilot; age 26; injuries: minor; student; medical: class 3, without waivers/limitations; seat: right; flight hours: 57 total, 57 in this make and model, 5 as pilot in command, 57 in the last 90 days, 42 in the last 30 days, 0 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 100° at 14 knots, gusting 22
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 93 °F, dew point 61 °F
- Altimeter: 29.76 inHg
- Observed at: KTTD

## 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 20090729013229A](https://openairdocs.org/incident/20090729013229A), Jul 29, 2009: Robsin R22BETA, Portland, OR, Substantial damage. (-23) Dual instruction, student performing autorotation with turn, came out of turn to align with the taxiway in a very nose low attitude. The instructor was…

## Docket (1 files)

The files NTSB released with the investigation on August 14, 2009, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=74398. 617 KB in all.

- Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 617 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40316988&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-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.

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