# NTSB LAX92FA154: Hughes 269C, N9597F, Hesperia, CA, March 28, 1992

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: March 28, 1992, 13:50 local (21:50 UTC)
- Place: Hesperia, CA
- Coordinates: 34.360496, -117.320892 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=34.3605&lon=-117.3209&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal, 1 serious
- Status: Completed, report June 30, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 27414
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX92FA154
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/27414/pdf
- Page: https://openairdocs.org/ntsb/LAX92FA154

## Probable cause

A FAILURE OF THE STUDENT PILOT TO MAINTAIN ADEQUATE ROTOR RPM. CONTRIBUTING TO THE ACCIDENT WAS A FAILURE OF THE INSTRUCTOR PILOT TO ADEQUATELY SUPERVISE THE TRAINING FLIGHT AND A DELAY IN CORRECTING A LOW ROTOR RPM CONDITION.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Loss of control - in flight, landing
  - rotor rpm - not maintained, dual student (cause)
  - remedial action - delayed, pilot in command(cfi) (contributing factor)
  - supervision - inadequate, pilot in command(cfi) (contributing factor)
- In flight collision with terrain/water, landing - flare/touchdown
  - terrain condition - mountainous/hilly

## Analysis

THE CERTIFICATED FLIGHT INSTRUCTOR AND A PRIVATE PILOT/COMMERCIAL STUDENT, WERE ON A DUAL INSTRUCTIONAL FLIGHT IN A HELICOPTER, TO PRACTICE PINNACLE APPROACHES, LANDINGS, AND TAKEOFFS.  THE AREA OF LANDING WAS LOCATED AT ABOUT 3,600 FEET MSL, NEAR THE TOP OF A STEEP MOUNTAIN RIDGE.  TWO APPROACHES TO THE PINNACLE LANDING ZONE RESULTED IN ONE GO-AROUND, AND ONE LANDING.  THE INSTRUCTOR PILOT REPORTED THAT THE STUDENT TENDED TO ALLOW THE MAIN ROTOR RPM TO DROOP WHEN ADDING POWER TO TERMINATE THE LANDING APPROACH.  ON THE THIRD APPROACH, THE RPM AGAIN STARTED TO DECREASE.  THE INSTRUCTOR PILOT TOOK CONTROL OF THE HELICOPTER AND ATTEMPTED TO INCREASE THE THROTTLE SETTING AND DECREASE COLLECTIVE PITCH TO RECOVER FROM THE LOW ROTOR RPM CONDITION.  MAIN ROTOR RPM CONTINUED TO DECREASE AND THE INSTRUCTOR ATTEMPTED TO LAND AT THE EDGE OF THE RIDGE.  THE HELICOPTER SLID BACKWARDS OVER THE EDGE OF THE MOUNTAIN AND BEGAN TO BREAK APART, TUMBLING 600 FEET DOWN THE MOUNTAIN SIDE.  A POST CRASH FIRE ERUPTED DURING THE BREAK-UP SEQUENCE.  THE INSTRUCTOR WAS EJECTED FROM HELICOPTER. THE STUDENT REMAINED IN THE WRECKAGE AND RECEIVED FATAL INJURIES.  THE POST ACCIDENT WRECKAGE EXAMINATION DISCLOSED NO EVIDENCE OF ANY PREEXISTING MECHANICAL FAILURES OR MALFUNCTIONS.

## Aircraft

- Registration: [N9597F](https://openairdocs.org/deregistered/N9597F-1992-07-13), registration cancelled 1992-07-13, S/N 640314 (OpenAirDocs)
- Reported make and model: HUGHES 269C
- Registry model: [Hughes 269C](https://openairdocs.org/model/hughes-269c) (registry code 4470504) (OpenAirDocs)
- Category: Helicopter
- Serial number: 640314
- Airframe hours: 5700
- Engines: LYCOMING HIO-360-D1A 190 horsepower reciprocating
- Damage: Destroyed
- Fire: On-Ground
- Flight: Instructional, Part 91
- Operator: Mojave Aviation Inc.
- Registered owner: Mojave Aviation Inc.
- Airworthiness certificate: Standard, Normal
- Last inspection: 100 hour, February 24, 1992, 18 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 35; airline transport, flight instructor, commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: right; flight hours: 7,630 total, 250 in this make and model, 106 in the last 90 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 190° at 7 knots
- Visibility: 30 statute miles
- Lowest ceiling: none
- Temperature: 64 °F, dew point 45 °F
- Altimeter: 29.00 inHg
- Observed at: VCV, 20 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 19920328007779A](https://openairdocs.org/incident/19920328007779A), Mar 28, 1992: Hughes 269C, Hesperia, CA, Destroyed, 1 fatal. During pinnacle landing practice, witnesses saw and heard the 269C rotors hit rocks, then tumble down mountainside

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.

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