# Accident 19980723017639A: Enstrm F28A, Pleasanton, CA, July 23, 1998

- Type: FAA accident report (Accident/Incident Data System), as reported
- Date: July 23, 1998, 19:00 local time
- Place: Pleasanton, CA
- Airport: Pleasanton
- Damage: Substantial damage
- Phase of flight: Pinnacle Landing
- Operating rules: General operating rules (Part 91)
- Location: 37.6791° N, 121.7493° W: From the FAA, an estimate near the named town, within about 3 miles
- Nearby events: https://openairdocs.org/map.md?lat=37.6791&lon=-121.7493&mi=10
- Aircraft: N288Q, a cancelled registration (https://openairdocs.org/deregistered/N288Q-2001-09-19) (OpenAirDocs)
- Registry model: Enstrom F-28A (registry code 3300406, https://openairdocs.org/model/enstrom-f-28a) (OpenAirDocs)
- Reported make and model: ENSTRM F28A
- Reported engine: LYC HIO360C1A
- People aboard: 2
- Fatal injuries: 0
- Pilot flight hours: 5,885 total, 36 in this make and model, 40 in the last 90 days
- NTSB investigation: [NTSB LAX98LA242](https://openairdocs.org/ntsb/LAX98LA242) (OpenAirDocs)
- FAA source: FAA Aviation Safety Information Portal (https://asip.faa.gov/)
- Page: https://openairdocs.org/incident/19980723017639A

## Narrative

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

(.4)THE DUAL STUDENT PERFORMED AN OFF-AIRPORT PINNACLE LANDING. THE CFI STATED THAT THE HELICOPTER BEGAN TO VIBRATE AND MOVED SIDEWAYS SO HE ROLLED ON POWER.  BY THE TIME THE HELICOPTER REACHED THE EDGE OF THE LANDING AREA, THE RPM HAD DECREASED AND HE COULD NOT REPOSITION THE AIRCRAFT.  THE CFI REPORTED THAT HE PEDAL-TURNED SO THAT THE TAIL WAS POINTING DOWNHILL, LOWERED THE COLLECTIVE, AND ROLLED OFF THE THROTTLE.  THE HELICOPTER SLID APPROXIMATELY 300 FEET OFF THE TOP OF THE HILL AND DOWN A 30-DEGREE SLOPE.  THE MAIN ROTOR BLADES CONTACTED THE GROUND BUT THE AIRCRAFT REMAINED UPRIGHT.  THE CFI REPORTED THAT THERE WERE NO MECHANICAL MALFUNCTIONS WITH THE AIRCRAFT PRIOR TO THE ACCIDENT.                                                     (-23)THE STUDENT PILOT OVER SHOOT THE INTENDED LANDING SPOT AND TOUCHED DOWN ON THE ALTERNATE LANDING SPOT THAT APPEARED SUITABLE.  THE INSTRUCTOR STATEMENT REFLECTED THAT THE HELICOPTER WAS ON THE GROUND AND STABLE BEFORE THE STUDENT REDUCED POWER.  THE TALL PRASS IN THE AREA WAS VERY SLIPPERY AND THE HELICOPTER WHICH WAS ON A SLOPE SLID DOWN THE HILL SIDE FOR ABOUT 300 FEET.  DURING THE HELICOPTER TRIP DOWN THE HILL THE ROTOR BLADES IMPACTED TH E HILL SIDE.

## 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 LAX98LA242](https://openairdocs.org/ntsb/LAX98LA242), Jul 24, 1998: Enstrom F28A (N288Q), Pleasanton, CA, substantial damage. Probable cause: The flight instructor's delayed remedial action and the student pilot's failure to maintain rotor RPM. A factor was the downhill terrain.

## Other reports on N288Q (1)

Matched to the same aircraft by N-number and date.

- [Incident 19940520021889I](https://openairdocs.org/incident/19940520021889I), May 20, 1994: Enstrm F28A (N288Q), Sacramento, CA. Lost power en route. Auto rotated to ground. NR3 intake valve stuck open and bent causing valve train failure.

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.

---
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.