# NTSB WPR09CA105: Robinson Helicopter R44 II, N944U, Bountiful, UT, February 1, 2009 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Data collection · Final report - Date: February 1, 2009, 12:00 local (19:00 UTC) - Place: Bountiful, UT - Coordinates: 41.231666, -111.805557 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=41.2317&lon=-111.8056&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Low altitude operation/event](https://openairdocs.org/ntsb-events/220) - Highest injury: Minor injuries - Injuries: 1 minor, 3 uninjured - Status: Completed, report April 15, 2009 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Salt Lake FAA FSDO - NTSB case key (mKey): 73303 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR09CA105 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/73303/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=73303 - Page: https://openairdocs.org/ntsb/WPR09CA105 ## Probable cause The pilot's improper decision to fly at low altitude while maneuvering in mountainous terrain in a canyon and inadvertently exceeding the climb capability of the helicopter. Contributing to the accident were a high density altitude, mountainous terrain, and a tailwind encountered during the attempted course reversal. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: climb rate](https://openairdocs.org/ntsb-findings/01062035): Aircraft › Aircraft oper/perf/capability · Capability exceeded (probable cause); cases with it: [Robinson Helicopter R44 II, 2 cases](https://openairdocs.org/ntsb-findings/01062035/cases.md?model=7640122), [All aircraft, 265 cases](https://openairdocs.org/ntsb-findings/01062035/cases.md) - [Info processing/decision: decision making/judgment](https://openairdocs.org/ntsb-findings/02041520): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Robinson Helicopter R44 II, 40 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md?model=7640122), [All aircraft, 3,098 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md) - [Terrain: mountainous/hilly terrain](https://openairdocs.org/ntsb-findings/03021010): Environmental issues › Physical environment · Effect on operation (probable cause); cases with it: [Robinson Helicopter R44 II, 4 cases](https://openairdocs.org/ntsb-findings/03021010/cases.md?model=7640122), [All aircraft, 329 cases](https://openairdocs.org/ntsb-findings/03021010/cases.md) - [Wind: tailwind](https://openairdocs.org/ntsb-findings/03034015): Environmental issues › Conditions/weather/phenomena · Effect on equipment (probable cause); cases with it: [Robinson Helicopter R44 II, 13 cases](https://openairdocs.org/ntsb-findings/03034015/cases.md?model=7640122), [All aircraft, 594 cases](https://openairdocs.org/ntsb-findings/03034015/cases.md) - [Temp/humidity/pressure: high density altitude](https://openairdocs.org/ntsb-findings/03031020): Environmental issues › Conditions/weather/phenomena · Effect on equipment (probable cause); cases with it: [Robinson Helicopter R44 II, 11 cases](https://openairdocs.org/ntsb-findings/03031020/cases.md?model=7640122), [All aircraft, 278 cases](https://openairdocs.org/ntsb-findings/03031020/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering-low-alt flying: Low altitude operation/event](https://openairdocs.org/ntsb-events/220) (defining event); cases with it: [Robinson Helicopter R44 II, 45 cases](https://openairdocs.org/ntsb-events/220/sequence.md?model=7640122), [All aircraft, 780 cases](https://openairdocs.org/ntsb-events/220/sequence.md) ## Analysis While en route to her destination, the pilot elected to fly the helicopter up a canyon toward rising terrain. Soon after making a low pass over a ridge above 8,000 feet mean sea level, the pilot increased collective in order to climb over upcoming higher terrain. As the collective was increased, the rotor rpm started to drop. The pilot immediately increased throttle, reversed course to fly downhill, and lowered the collective. During the turn, the helicopter encountered a quartering tailwind and began to settle toward the snow-covered down-sloping terrain. Soon thereafter the helicopter contacted the terrain, bounced back into the air, and a main rotor blade severed the tail boom. The helicopter rotated 180 degrees, impacted the terrain, and rolled over. According to the pilot there was no evidence of an engine power loss or any anomaly with the flight control system. ## Factual narrative While en route to her destination, the pilot elected to fly the helicopter up a canyon toward rising terrain. Soon after making a "low pass" over a ridge above 8,000 feet mean sea level (MSL), the pilot increased collective in order to climb over upcoming terrain. As the collective was increased, the rotor RPM started to drop. The pilot immediately increased throttle, reversed course to fly downhill, and lowered the collective. During the turn, the helicopter encountered a quartering tailwind and began to settle toward the snow-covered terrain. Soon thereafter the helicopter contacted the terrain, but bounced back into the air. Immediately thereafter a main rotor blade severed the tail boom, and the helicopter impacted the terrain. According to the pilot, there was no evidence of an engine power loss or any anomaly with the flight control system. ## Aircraft - Registration: [N944U](https://openairdocs.org/deregistered/N944U-2017-09-26), registration cancelled 2017-09-26, S/N 10766, built 2005 (OpenAirDocs) - Reported make and model: ROBINSON HELICOPTER COMPANY R44 II - Registry model: [Robinson Helicopter R44 II](https://openairdocs.org/model/robinson-helicopter-r44-ii) (registry code 7640122) (OpenAirDocs) - Registry engine: [Lycoming IO-540 series](https://openairdocs.org/engine/lycoming-io-540-series) (registry code 41530, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: 10766 - Airframe hours: 2035 - Engines: LYCOMING IO-540-AE1A5 205 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Upper Limit Aviation - Registered owner: Tumbleweed Leasing Company Inc - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, January 28, 2009 - Departed: kslc, SALT LAKE CITY, UT - Destination: 42u, MORGAN, UT ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 21; injuries: none; commercial, flight instructor; instrument ratings: helicopter; medical: class 2, without waivers/limitations; last flight review August 23, 2008; seat: right; flight hours: 524 total, 101 in this make and model, 433 as pilot in command, 194 in the last 90 days, 63 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Visibility: 10 statute miles - Lowest ceiling: none ## 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 20090201000379A](https://openairdocs.org/incident/20090201000379A), Feb 1, 2009: Robsin R44II, Kaysville, UT, Substantial damage. Pilot was giving family members a helicopter ride and decided to fly up a canyon. The required power to climb exceeded the available power. The pilot reduced… ## Other investigations on N944U (1) 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. - [NTSB DEN05CA138](https://openairdocs.org/ntsb/DEN05CA138), Sep 9, 2005: Robinson R44 II (N944U), Jackson, WY, substantial damage. Probable cause: the pilot's failure to maintain aircraft control during initial takeoff climb resulting in an uncontrolled descent and impact with terrain. A contributing factor was the pilot's encounter in settling… ## Docket (1 files) The files NTSB released with the investigation on February 20, 2009, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=73303. 611 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 611 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40308021&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. --- 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.