Accident Cessna 320D Skyknight N9HS, Monday 4 July 1988
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Date:Monday 4 July 1988
Time:16:52
Type:Silhouette image of generic C320 model; specific model in this crash may look slightly different    
Cessna 320D Skyknight
Owner/operator:private
Registration: N9HS
MSN: 320D0028
Year of manufacture:1965
Total airframe hrs:2731 hours
Engine model:Continental TSIO-520-B
Fatalities:Fatalities: 4 / Occupants: 4
Other fatalities:0
Aircraft damage: Destroyed
Category:Accident
Location:Mammoth Lakes, CA -   United States of America
Phase: En route
Nature:Private
Departure airport:Mammoth Lakes, CA (MMH)
Destination airport:Torrance, CA (TOA)
Investigating agency: NTSB
Confidence Rating: Accident investigation report completed and information captured
Narrative:
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. CAUSE:

Accident investigation:
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Investigating agency: NTSB
Report number: LAX88FA245
Status: Investigation completed
Duration:
Download report: Final report

Sources:

NTSB: https://www.ntsb.gov/ntsb/brief.asp?ev_id=20001213X26258

Revision history:

Date/timeContributorUpdates
24-Oct-2008 10:30 ASN archive Added
16-Nov-2022 20:34 Ron Averes Updated [Aircraft type, ]

Corrections or additions? ... Edit this accident description

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