# Accident 19990518005389A: Robsin R22ALPHA, San Luis Obispo, CA, May 18, 1999

- Type: FAA accident report (Accident/Incident Data System), as reported
- Date: May 18, 1999, 17:30 local time
- Place: San Luis Obispo, CA
- Damage: Substantial damage
- Phase of flight: Sfl Autorotation
- Operating rules: General operating rules (Part 91)
- Location: 35.2504° N, 120.6192° W: From the FAA, an estimate near the named town, within about 3 miles
- Nearby events: https://openairdocs.org/map.md?lat=35.2504&lon=-120.6192&mi=10
- Aircraft: N8558N, a cancelled registration (https://openairdocs.org/deregistered/N8558N-2000-08-04) (OpenAirDocs)
- Registry model: Robinson Helicopter R22 ALPHA (registry code 7640104, https://openairdocs.org/model/robinson-helicopter-r22-alpha) (OpenAirDocs)
- Reported make and model: ROBSIN R22ALPHA
- Reported engine: LYC O320B3C
- Fatal injuries: 0
- Pilot flight hours: 369 total, 364 in this make and model, 164 in the last 90 days
- NTSB investigation: [NTSB LAX99LA186](https://openairdocs.org/ntsb/LAX99LA186) (OpenAirDocs)
- FAA source: FAA Aviation Safety Information Portal (https://asip.faa.gov/)
- Page: https://openairdocs.org/incident/19990518005389A

## Narrative

As the FAA filed it, in capitals; the FAA replaces private details with ^PRIVACY DATA OMITTED^.

ROBINSON R-22 HELICOPTER WAS INVOLVED IN AUTO ROTATION PRACTICE WHEN THE ACFT CAUGHT A DOWN DRAFT, STRUCK THE GROUND HARD, ROLLED OVER, AND WAS DESTROYED, OTHER CIRCUMSTANCES ARE UNKNOWN. (.4)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.                                                                                                       (-23)LAX99LA1186

## The NTSB's investigation of this event (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 LAX99LA186](https://openairdocs.org/ntsb/LAX99LA186), May 19, 1999: Robinson R22A (N8558N), San Luis Obispo, CA, substantial damage. 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.

From the FAA Accident/Incident Data System. Reports are matched to registry aircraft by N-number and event date, checked against the reported make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. For accidents, the NTSB's own investigation is the fuller record.

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