# NTSB LAX88FA245: Cessna 320D, N9HS, Mammoth Lakes, CA, July 4, 1988

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: July 4, 1988, 16:52 local (23:52 UTC)
- Place: Mammoth Lakes, CA
- Coordinates: 37.580913, -118.839843 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=37.5809&lon=-118.8398&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 4 fatal
- Status: Completed, report March 13, 1989
- Report: Approved by Office Director
- NTSB case key (mKey): 25842
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX88FA245
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/25842/pdf
- Page: https://openairdocs.org/ntsb/LAX88FA245

## Sequence of events

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

- Loss of control - in flight, climb - to cruise
  - in-flight planning/decision - improper, pilot in command (cause)
  - procedures/directives - inattentive, pilot in command (cause)
  - airspeed - not maintained, pilot in command (cause)
  - stall - inadvertent, pilot in command (cause)
  - weather condition - high density altitude (contributing factor)
  - aircraft weight and balance - exceeded, pilot in command (contributing factor)
  - instructions,written/verbal - disregarded, pilot in command (contributing factor)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

THE PILOT EXECUTED A LEFT (SOUTH) CROSSWIND DEPARTURE TOWARDS HIGHER TERRAIN AFTER DEPARTING RUNWAY 27; THE PLT WAS FOLLOWING A SLOWER SINGLE ENGINE AIRPLANE THAT HAD PRECEDED HIS DEPARTURE. GROUND WITNESSES REPORTED THAT AS THE AIRPLANE APPROACHED THE HIGHER TERRAIN IT ENTERED INTO A LEFT BANKING TURN. DURING THE TURN THE AIRPLANE'S WINGS OSCILLATED RAPIDLY. THE AIRPLANE STALLED AND CRASHED INTO THE CENTER DIVIDER OF CALIF STATE HWY 395 WHICH IS ADJACENT TO & PARALLELS THE EAST/WEST RUNWAY. THE POST ACCIDENT AIRPLANE/ENGINE EXAMINATION DISCLOSED NO EVIDENCE OF ANY PREEXISTING MALFUNCTIONS OR FAILURES. THE AIRPLANE HAD EXCEEDED ITS MAX GROSS T.O. WEIGHT AND IT WAS NEAR ITS AFT CENTER OF GRAVITY LIMITS. THE PLT HAD COMPLAINED TO HIS DR. ABOUT EPISODES OF FORGETFULNESS AND CONFUSION. THE DR. RECOMMENDED THAT THE PILOT CEASE ANY FLYING ACTIVITIES UNTIL HIS MEDICAL CONDITION WAS DIAGNOSED AND TREATED. THE PLT DID NOT HEED THE DRS. ADVICE.

## Aircraft

- Registration: [N9HS](https://openairdocs.org/deregistered/N9HS-2013-07-03), registration cancelled 2013-07-03, S/N 320D0028, built 1965 (OpenAirDocs)
- Reported make and model: CESSNA 320D
- Registry model: [Cessna 320D](https://openairdocs.org/model/cessna-320d) (registry code 2074512) (OpenAirDocs)
- Registry engine: [Continental TSIO-520 series](https://openairdocs.org/engine/continental-tsio-520-series) (registry code 17040, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 320D0028
- Airframe hours: 2731
- Engines: CONTINENTAL TSIO-520-B 280 horsepower reciprocating
- Damage: Destroyed
- Flight: Personal, Part 91
- Registered owner: J. T. Thompson & G. Sturdevant
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, August 18, 1987, 37 hours before
- Departed: MMH, MAMMOTH LAKES, CA
- Destination: TOA, TORRANCE, CA
- Airport: MMH, Mammoth/June Lakes, runway 27, 7,000 × 100 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 52; private; airplane ratings: multi-engine land, single-engine sea, single-engine land; instrument ratings: airplane; medical: class 3, valid medical--w/ waivers/lim; seat: left; toxicology performed; flight hours: 1,789 total, 102 in this make and model, 2 in the last 90 days, 2 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 270° at 20 knots, gusting 30
- Visibility: 50 statute miles
- Lowest ceiling: none
- Temperature: 72 °F
- Altimeter: 30.00 inHg
- Observed at: MMH, 1 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 19880704024789A](https://openairdocs.org/incident/19880704024789A), Jul 4, 1988: Cessna 320D, Mammoth Lakes, CA, Destroyed, 4 fatal. Made climbing turn into rising terrain. Stalled. Factors. Behind slow aircraft. Over gross. Non fly medical conditi

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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