# NTSB ERA20LA004: Bell OH 58A, N911RW, Fort Meade, FL, October 3, 2019 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 3 · Limited · Final report - Date: October 3, 2019, 15:03 local (19:03 UTC) - Place: Fort Meade, FL - Coordinates: 27.702222, -81.76889 - Nearby events: https://openairdocs.org/map.md?lat=27.7022&lon=-81.7689&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-hover: Dynamic rollover](https://openairdocs.org/ntsb-events/231) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Eastern Region Aviation - Parties: FAA/FSDO - NTSB case key (mKey): 100372 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA20LA004 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/100372/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=100372 - Page: https://openairdocs.org/ntsb/ERA20LA004 ## Probable cause The pilot's failure to maintain control of the helicopter, which resulted in a dynamic rollover and impact with terrain. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Bell OH-58A, 12 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=1181579), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Performance/control parameters: lateral/bank control](https://openairdocs.org/ntsb-findings/01062023): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Bell OH-58A, 3 cases](https://openairdocs.org/ntsb-findings/01062023/cases.md?model=1181579), [All aircraft, 390 cases](https://openairdocs.org/ntsb-findings/01062023/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering-hover: Dynamic rollover](https://openairdocs.org/ntsb-events/231) (defining event); cases with it: [Bell OH-58A, 3 cases](https://openairdocs.org/ntsb-events/231/sequence.md?model=1181579), [All aircraft, 161 cases](https://openairdocs.org/ntsb-events/231/sequence.md) ## Analysis The pilot was attempting to rescue a gyroplane pilot who made a forced landing in a phosphate pit and gypsum pond by having him grab the right skid of the helicopter and lift him to safety. The pilot anticipated that he would have to compensate for the change in the helicopter's center of gravity when the gyroplane pilot grabbed the skid. The gyroplane pilot’s first two attempts to grab the helicopter’s right skid were unsuccessful. The helicopter pilot stated that the gyroplane pilot’s third attempt was more aggressive than the previous two attempts and that he was not prepared for the sudden center-of-gravity shift that resulted once the gyroplane pilot grabbed the right skid. The helicopter then entered a dynamic rollover to the right and impacted the gypsum pond, resulting in substantial damage to the main rotor blades, tail rotor, and the tailboom. ## Factual narrative On October 3, 2019, about 1503 eastern daylight time, a Bell OH-58A helicopter, N911RW, sustained substantial damage when it was involved in an accident near Fort Meade, Florida. The commercial pilot and the individual being rescued were not injured. The helicopter was registered to and operated by the Polk County, Florida, sheriff's office as a Title 14 Code of Federal Regulations Part 91 public-use flight. The pilot was dispatched from Bartow Executive Airport (BOW), Bartow, Florida, about 1412 to provide aerial support for the pilot of a gyroplane who had made a forced landing in a phosphate pit and gypsum pond. The foliage in the gypsum pond was about 6 to 9 ft tall. The helicopter pilot stated that the gyroplane pilot was standing on his seat while holding onto the rotor blades. The helicopter pilot was concerned that the gyroplane pilot would sink into the gypsum, so he attempted to rescue the gyroplane pilot by having him grab the helicopter's right skid and then lifting him to safety. The helicopter pilot anticipated that he would have to compensate for the change in the helicopter's center of gravity (CG) when the gyroplane pilot grabbed the skid. During the first two attempts, the gyroplane pilot was unable to hold on to the skid because his hands were covered in gypsum. During the third attempt, the gyroplane pilot had repositioned himself closer to the helicopter's right skid, and the helicopter pilot reported that, "without hesitation and without warning, [the gyroplane pilot] jumped up in the air towards my skid, grabbing the skid in the air, causing his entire weight to be forced onto my skid.” The helicopter pilot further reported that the helicopter’s CG had “immediately changed,” which caused the helicopter to descend and make “an abrupt and violent roll” toward the right. The helicopter pilot immediately increased collective to prevent striking the gyroplane with the helicopter's skid but reported that the "roll was tremendous and without warning." The pilot tried to push the cyclic forward to increase speed and lift, but the helicopter continued to roll to the right and then impacted the gypsum pond, which resulted in substantial damage to the helicopter’s main rotor blades, tail rotor, and tailboom. The pilot reported no mechanical malfunctions at the time of the accident. The Federal Aviation Administration's Rotorcraft Flying Handbook (FAA-H-8083-21) states the following about a helicopter’s lateral roll tendency, referred to as a “dynamic rollover”: For dynamic rollover to occur, some factor has to first cause the helicopter to roll or pivot around a skid, or landing gear wheel, until its critical rollover angle is reached. Then, beyond this point, main rotor thrust continues the roll and recovery is impossible. If the critical rollover angle is exceeded, the helicopter rolls on its side regardless of the cyclic corrections made. Dynamic rollover begins when the helicopter starts to pivot around its skid or wheel. Thiscan occur for a variety of reasons, including the failure to remove a tiedown or skid securing device, or if the skid or wheel contacts a fixed object while hovering sideward, or if the gear is stuck in ice, soft asphalt, or mud. Dynamic rollover may also occur if you do not use the proper landing or takeoff technique or while performing slope operations. Whatever the cause, if the gear or skid becomes a pivot point, dynamic rollover is possible if you do not use the proper corrective technique. ## Aircraft - Registration: [N911RW](https://openairdocs.org/deregistered/N911RW-2021-06-08), registration cancelled 2021-06-08, S/N 72-21147 (OpenAirDocs) - Reported make and model: Bell OH 58A (No Series) - Registry model: [Bell OH-58A](https://openairdocs.org/model/bell-oh-58a) (registry code 1181579) (OpenAirDocs) - Category: Helicopter - Serial number: 72-21147 - Year built: 1972 - Airframe hours: 9829 - Engines: Rolls Royce T63-A720 420 horsepower turbo shaft - Damage: Substantial damage - Flight: Public aircraft - local, Public use - Airworthiness certificate: None - Last inspection: AAIP, September 13, 2019 - Departed: BOW, Bartow, FL - Destination: Fort Meade, FL - Flight plan: Company VFR - Equipment: Electronic primary flight display, Electronic multifunction display, ADS-B ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 52; injuries: none; commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane, helicopter; medical: class 2, with waivers/limitations; last flight review August 7, 2019; seat: right; restraint: 4-point; flight hours: 4,287 total, 2,500 in this make and model, 3,866 as pilot in command, 49 in the last 90 days, 19 in the last 30 days, 0 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 60° at 12 knots, gusting 18 - Visibility: 10 statute miles - Temperature: 90 °F, dew point 64 °F - Altimeter: 29.95 inHg - Observed at: BOW, 17 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 20191003018719A](https://openairdocs.org/incident/20191003018719A), Oct 3, 2019: Bell OH-58A, Ft Meade, FL, Substantial damage. Aircraft N911RW operated by the polk county Florida sheriff office responded to a report of a downed aircraft. The downed aircraft was in a remote mining… ## Docket (2 files) The files NTSB released with the investigation on April 12, 2022, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=100372. 6.4 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 9 pages, 4.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9929887&FileExtension=pdf&FileName=6120_Redacted-Rel.pdf - Photos (item 2, PDF, 3 pages, 3 photos, 1.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9929761&FileExtension=pdf&FileName=Photo%20Array-Rel.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.