# NTSB NYC08TA183: Robinson R44 II, N911GJ, Lake Wales, FL, May 15, 2008 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Final report - Date: May 15, 2008, 16:40 local (20:40 UTC) - Place: Lake Wales, FL - Coordinates: 27.899723, -81.455276 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=27.8997&lon=-81.4553&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-flare/touchdown: Abnormal runway contact](https://openairdocs.org/ntsb-events/090) - Highest injury: Minor injuries - Injuries: 2 minor - Status: Completed, report May 12, 2009 - Report: Approved by Office Director - Parties: FAA/FSDO - NTSB case key (mKey): 68020 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC08TA183 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/68020/pdf - Page: https://openairdocs.org/ntsb/NYC08TA183 ## Probable cause The pilot's improper recovery from a practice autorotation. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Action: incorrect action performance](https://openairdocs.org/ntsb-findings/02041015): Personnel issues › Action/decision · Instructor/check pilot (probable cause); cases with it: [Robinson Helicopter R44 II, 12 cases](https://openairdocs.org/ntsb-findings/02041015/cases.md?model=7640122), [All aircraft, 1,386 cases](https://openairdocs.org/ntsb-findings/02041015/cases.md) - [Main rotor system: main rotor blade system](https://openairdocs.org/ntsb-findings/01046210): Aircraft › Aircraft propeller/rotor · Damaged/degraded; cases with it: [Robinson Helicopter R44 II, 4 cases](https://openairdocs.org/ntsb-findings/01046210/cases.md?model=7640122), [All aircraft, 60 cases](https://openairdocs.org/ntsb-findings/01046210/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 final: Simulated/training event](https://openairdocs.org/ntsb-events/600); cases with it: [Robinson Helicopter R44 II, 2 cases](https://openairdocs.org/ntsb-events/600/sequence.md?model=7640122), [All aircraft, 173 cases](https://openairdocs.org/ntsb-events/600/sequence.md) - [Landing-flare/touchdown: Abnormal runway contact](https://openairdocs.org/ntsb-events/090) (defining event); cases with it: [Robinson Helicopter R44 II, 6 cases](https://openairdocs.org/ntsb-events/090/sequence.md?model=7640122), [All aircraft, 1,506 cases](https://openairdocs.org/ntsb-events/090/sequence.md) ## Analysis The certificated flight instructor (CFI) attempted a practice autorotation to a power recovery over a runway. During the recovery attempt, the helicopter hit the runway in a level attitude, bounced, touched down again, and rolled over. Winds at the time were variable at 5 knots. No preimpact mechanical anomalies were noted by ether the pilots, or by a Federal Aviation Administration inspector who examined the helicopter after the accident. The CFI reported 6,766 hours of flight experience as pilot in command, which included about 300 hours in the accident helicopter make and model. ## Factual narrative On May 15, 2008, at 1640 eastern daylight time, a Robinson R44 II, N911GJ, operated by the Polk County, Florida, Sheriffs Office, was substantially damaged during a practice autorotation at Lake Wales Municipal Airport (X07), Lake Wales, Florida. The certificated flight instructor (CFI) and the certificated commercial pilot sustained minor injuries. Visual meteorological conditions prevailed, and no flight plan was filed for the public use training flight which departed Bartow Municipal Airport (BOW), Bartow, Florida, approximately 1 hour earlier. According to the CFI, he was demonstrating an autorotation to runway 6, which he entered at "800 feet indicated and at zero airspeed." He lowered the nose of the helicopter and attained a 60-knot descent with a rotor rpm of 95 percent. At 40 feet above the ground (agl), he began a flare and began "rolling throttle on." At 8 feet agl, he raised the collective; however, the helicopter impacted the runway in a level attitude, bounced, landed again, and rolled onto its left side. According to the commercial pilot, the rotor and engine rpm remained at the "low end" of the green (normal) range during the autorotation. Approximately 500 feet agl, the CFI started to decelerate the helicopter, and approximately 40 feet agl, he began to add power as the rotor rpm began decreasing. The helicopter continued its descent, and impacted the runway in a level attitude. It then bounced, veered to the right, and rolled over on its left side. The CFI reported 6,766 hours of flight experience as pilot in command in rotorcraft, 300 hours in make and model, 60 hours of flight experience within the 90 days preceding the accident flight, and 1,500 hours of flight time as a CFI. The reported weather at BOW, located approximately 8 miles from the accident site, at 1650, included variable winds at 5 knots, visibility 8 miles, lowest cloud layer at 25,000 feet, temperature 31 degrees Celsius (C), dew point 12 degrees C, and an altimeter setting of 30.02 inches of mercury. According to a Federal Aviation Administration (FAA) inspector, the helicopter came to rest, on its left side at the approach end of runway 6. All major components were accounted for at the scene, and flight control continuity was confirmed from the cockpit to all flight control surfaces. No preimpact mechanical anomalies were noted by either the pilots or the FAA inspector. According to the Robinson R44 II Pilot's Operating Handbook, Chapter 4, Normal Procedures, Practice Autorotation Power Recovery: 1. Lower collective to down stop and adjust throttle as required for small tachometer needle separation. CAUTION To avoid inadvertent engine stoppage, do not roll throttle to full idle. Roll throttle off smoothly only enough for a small visible needle split. 2. Raise collective as required to keep rotor RPM from going above green arc and adjust throttle for small needle separation. 3. Keep RPM in green arc and airspeed 60 to 70 KIAS [knots indicated airspeed] 4. Atabout 40 feet AGL, begin cyclic flare to reduce rate of descent and forward speed. 5. At about 8 feet AGL, apply forward cyclic to level aircraft and raise collective to control descent. ADD throttle if required to keep RPM in green arc. According to the FAA Airplane Rotorcraft Flying Handbook FAA-H-8083-21, Chapter 11, Helicopter Emergencies, Power Recovery from Practice Autorotation some of the common errors associated with this maneuver are: 1. Initiating recovery too late, requiring a rapid application of controls, resulting in overcontrolling. 2. Failing to obtain and maintain a level attitude near the surface. 3. Failing to coordinate throttle and collective pitch properly, resulting in either an engine overspeed or a loss of r.p.m. 4. Failing to coordinate proper antitorque pedal with the increase in power. ## Aircraft - Registration: [N911GJ](https://openairdocs.org/deregistered/N911GJ-2010-04-02), registration cancelled 2010-04-02, S/N 11054, built 2006 (OpenAirDocs) - Reported make and model: Robinson 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: 11054 - Airframe hours: 817 - Engines: Lycoming IO-540-AEI A5 2058 horsepower reciprocating - Damage: Substantial damage - Flight: Public aircraft - local, Part 91 - Registered owner: Polk County Sheriff's Office - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, May 1, 2006, 19 hours before - Departed: BOW, Bartow, FL - Destination: X07, Lake Wales, FL - Airport: X07, Lake Wales Municiple Airport, runway 06, 3,999 × 100 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Flight instructor; age 48; injuries: minor; flight instructor, commercial; instrument ratings: helicopter; medical: class 2, with waivers/limitations; last flight review October 1, 2007; seat: right; flight hours: 6,766 total, 300 in this make and model, 6,766 as pilot in command, 60 in the last 90 days, 20 in the last 30 days, 5 in the last 24 hours - Pilot; age 39; injuries: minor; commercial; airplane ratings: single-engine land; medical: class 2, with waivers/limitations; last flight review October 1, 2007; seat: right; flight hours: 1,733 total, 1,639 as pilot in command, 150 in the last 90 days, 60 in the last 30 days, 3 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: variable at 5 knots - Visibility: 8 statute miles - Lowest ceiling: 25,000 ft broken - Temperature: 88 °F, dew point 54 °F - Altimeter: 30.02 inHg - Observed at: BOW, 10 nm away ## 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 20080515834829A](https://openairdocs.org/incident/20080515834829A), May 15, 2008: Robsin R44, Lake Wales, FL, Substantial damage. (-23) During a recurrent training flight in the polk co. sheriff's R-44, instructor [privacy data omitted] was demonstrating a zero airspeed autorotation to… 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.