ERA21LA024 · Robinson R22 BETA
Blue Ridge Helicopters Robinson R22 BETA · Accident: powerplant system/component malfunction/failure on approach
From Gwinnett County Briscoe Field (LZU) to an unrecorded destination
Event
- NTSB case
- ERA21LA024
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- Event fatalities
- Unknown
- Ground fatalities
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Robinson R22 BETA
- Aircraft type
- Robinson R22
- Category
- Helicopter
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N566BC
- Operator
- Blue Ridge Helicopters
- Onboard fatalities
- Unknown
- Route
- From Gwinnett County Briscoe Field (LZU), Lawrenceville, GATo not recorded
- Aircraft age
- About 12 years (built 2008)
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Approach · VFR pattern downwind
- Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Powerplant system/component malfunction/failure
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Aircraft › Fluids/miscellaneous hardware
- Personnel issues › Task performance
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The pilot was practicing touch-and-go landings during a personal flight in a helicopter. As the helicopter was turning onto a left crosswind during the fifth circuit around the pattern, the pilot heard a “metal against metal” noise, and the helicopter “jerked.” As he began to look for a clearing to land the helicopter, it jerked again, and the pilot thought that the helicopter was losing power. The pilot was unable to reach a clear area, and the helicopter descended “straight down” through trees and collided with the ground, resulting in substantial damage to the helicopter’s fuselage, tailboom, main rotor, and tail rotor and serious injuries to the pilot.
Postaccident examination of the wreckage found that most of the drive system vee-belts were missing; only a small 2-ft portion of one vee-belt was found. Further examination of the wreckage revealed that the engine cooling fan attachment bolts were loose and could be easily turned with a wrench. The paint around the fanwheel-to-hub hardware was displaced, and surface corrosion and fretting residue were found on the exposed metal around the hardware. This evidence was indictive of the bolts having been loose for a period of time, and it is likely that the condition of the bolts would have resulted in the cooling fan imparting vibratory loads to the helicopter. The cooling fan vibration likely allowed the belt tension actuator to incrementally overextend, resulting in the failure of the vee-belts and the loss of power to the rotor system.
The helicopter operator had not complied with a service bulletin that addressed an issue with the belt tension actuator. According to the airframe manufacturer, taking the action described in the service bulletin would have prevented the actuator from overextending by incorporating an electronic time delay. Also, there was no record of fanwheel replacement at the most recent overhaul, which was required by the manufacturer. The fanwheel hardware should also have been inspected by maintenance personnel at the last 100-hour inspection and by the pilot during the preflight inspection.
Probable cause
Maintenance personnel’s failure to properly secure the engine cooling fan attachment bolts, leading to vibration of the cooling fan, the overextension of the tension belt actuator, the failure of the drive system vee-belts, and the loss of power to the rotor system. Contributing to the accident was the failure of the operator to incorporate the manufacturer’s service bulletin addressing the prevention of belt tension actuator overextension, and the failure of maintenance personnel and the pilot to observe the loose fanwheel bolts during the most recent 100-hour inspection and during the preflight inspection of the helicopter (respectively).
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record ERA21LA024
- Event ID
- 20201019102162
- Case number
- ERA21LA024
- Dataset
- full-current
- Source SHA-256
- 5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status, coordinates, cause areas. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 72431ce3f6efbef92fd0fe173fa4770b48376f02817e9b3e8ed4fae43139d233; retrieved 2026-09-16T13:15:16.102Z.