# NTSB LAX90FA060: McDonnell Douglas 369E, N1604L, Santa Rosa, CA, December 29, 1989

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: December 29, 1989, 11:30 local (19:30 UTC)
- Place: Santa Rosa, CA
- Coordinates: 36.530872, -120.95977 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=36.5309&lon=-120.9598&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal, 1 serious, 3 minor
- Status: Completed, report August 26, 1994
- Report: Approved by Office Director
- NTSB case key (mKey): 26603
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX90FA060
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/26603/pdf
- Page: https://openairdocs.org/ntsb/LAX90FA060

## Probable cause

THE PILOT'S IMPROPER PREFLIGHT PLANNING/DECISION WHICH RESULTED IN THE LOSS OF TAIL ROTOR EFFECTIVENESS. CONTRIBUTING TO THE ACCIDENT WAS THE PILOT ALLOWING THE MAXIMUM GROSS WEIGHT OF THE AIRCRAFT TO BE EXCEEDED, AND THE TAILWIND.

## Sequence of events

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

- Loss of control - in flight, takeoff - initial climb
  - weather condition - tailwind (contributing factor)
  - planning/decision - improper, pilot in command (cause)
  - aircraft weight and balance - exceeded, pilot in command (contributing factor)
  - directional control - not possible, pilot in command (contributing factor)
  - lack of total experience in type of aircraft, pilot in command (contributing factor)
- In flight collision with terrain/water, descent - uncontrolled
  - terrain condition - ground

## Analysis

THE PILOT EXECUTED AN IMMEDIATE LEFT DOWNWIND CLIMBING TURN WHEN HE DEPARTED THE HELIPAD AND EXPERIENCED A LOSS OF TAIL ROTOR EFFECTIVENESS. BEFORE DEPARTING, THE PILOT FAILED TO ACCOUNT FOR THE DOWNWIND TURN AND THE HELICOPTER'S EXCEEDING THE MAXIMUM GROSS WEIGHT. THE POST ACCIDENT INVESTIGATION DISCLOSED THE LATERAL TRIM MOTOR EXCEEDED ITS PHYSICAL EXTENSION LIMITS WHICH INDICATES THAT THE TRIM MOTOR WAS OPERATING DURING THE IMPACT SEQUENCE WHEN ITS AIRFRAME ATTACHMENT POINT WAS BROKEN.

## Aircraft

- Registration: [N1604L](https://openairdocs.org/deregistered/N1604L-2013-09-13), registration cancelled 2013-09-13, S/N 0266E (OpenAirDocs)
- Reported make and model: McDonnell Douglas 369E
- Registry model: [Mcdonnell Douglas Helicopter 369E](https://openairdocs.org/model/mcdonnell-douglas-helicopter-369e) (registry code 3027369) (OpenAirDocs)
- Registry engine: [Allison 250-C20 series](https://openairdocs.org/engine/allison-250-c20-series) (registry code 03020, turbo-prop) (OpenAirDocs)
- Category: Helicopter
- Serial number: 0266E
- Airframe hours: 367
- Engines: ALLISON 250-C20 375 horsepower turbo shaft
- Damage: Destroyed
- Flight: Business, Part 91
- Operator: Interwest, Inc.
- Registered owner: John M. & Ona R. Roth
- Airworthiness certificate: Standard, Normal
- Last inspection: 100 hour, November 21, 1989
- Departed: STS
- Airport: STS, Sonoma County

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 34; airline transport, flight instructor, commercial; airplane ratings: multi-engine land, single-engine sea, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 4,123 total, 57 in this make and model, 3,705 as pilot in command, 106 in the last 90 days, 27 in the last 30 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 310° at 5 knots
- Visibility: 30 statute miles
- Lowest ceiling: none
- Temperature: 59 °F, dew point 37 °F
- Altimeter: 30.00 inHg

## 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 19891229054279A](https://openairdocs.org/incident/19891229054279A), Dec 29, 1989: Hughes 369E, Santa Rosa, CA, Destroyed, 1 fatal. Lost control on climbout when cyclic stick vibrated. 3 turn spin to ground. Overgross. Aft CG. Cyclic trim switch.

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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