LAX99LA186 · Robinson R22A
Robinson R22A · Accident: loss of control in flight on approach
From San Luis County Regional Airport (SBP) to an unrecorded destination
Event
- NTSB case
- LAX99LA186
- 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
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- 0
- 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 R22A
- 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
- N8558N
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From San Luis County Regional Airport (SBP)To not recorded
- Aircraft age
- Not recorded
- 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 final
- First occurrenceThe 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
- Loss of control in flight
- 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
- Dual student › Cyclic, inadvertent activation
- Dual student › Rotor RPM, not maintained
- Pilot in command(cfi) › Supervision, inadequate
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The instructor stated the student entered a practice autorotation at 1,400 feet (600 feet agl) to a landing site on top of a hill about 800 feet high. As the flare was initiated at 40 to 50 feet, the instructor mentioned to the student that the cyclic trim was engaged. When the student unexpectedly reached forward and tried to push the trim control knob in, he inadvertently pushed forward on the cyclic control. The instructor said this pitched the nose of the helicopter down and resulted in a bleed off of main rotor rpm. When the low rotor horn and warning light came on the instructor took control of the helicopter and rolled in throttle. The lowest rpm he recalls seeing was slightly above 90 percent. He made a left turn to avoid hitting the hill and encountered a strong downdraft due to the gusty winds. The helicopter touched down on the left skid during the turn and rolled over twice.
Probable cause
The student's inadvertent and uncoordinated application of forward cyclic during an autorotation flare, which resulted in a loss of main rotor rpm; and the flight instructor's inadequate supervision.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record LAX99LA186
- Event ID
- 20001212X18815
- Case number
- LAX99LA186
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
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: local date, investigation status. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 1999-05-19.
- API snapshot SHA-256: a60031c208e0c6d9b62c367910949893ca33e07d5d80bf84b8bb1eae94a95f81; retrieved 2026-09-21T20:32:20.013Z.