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NTSB Report
December 1, 1990 · Aero Commander 690A · N400N
Ryderwood, WA
Overview
Report Status
Probable Cause
Event Type
Accident
Date
December 1, 1990
Injury Outcomes
6 injuries (5 fatalities, 1 serious injury)
Location
Ryderwood, WA
Aircraft
Aero Commander 690A
Tail Number
N400N
Operator
Aero Air
Injuries
Fatal
Aircraft Damage
Destroyed
NTSB Number
SEA91FA027
AS THE FLT WAS APCHG THE DESTN, AT NGT, THE PLT OBTAINED VECTORS FOR A DSCNT OVER MOUNTAINOUS TERRAIN. DURING THE APCH, HE CANCELLED THE IFR FLT PLAN & THE ACFT DSNDD BELOW RADAR COVERAGE. SUBSEQUENTLY, THE ACFT CRASHED IN MOUNTAINOUS TERRAIN, NORTHWEST OF THE DESTN ARPT. IMPACT OCCURRED IN A WOODED AREA AT AN ELEVATION OF ABOUT 2700 FT. THE ELT DID NOT ACTIVATE DURING THE ACDNT. A SEARCH WAS INITIATED ON 12/1/90, BUT THE ACFT & SURVIVING PASSENGER WERE NOT FND UNTIL THE NEXT DAY. THE CANADIAN ATP PLT & OTHER 4 PASSENGERS WERE FATALLY INJURED. AFTER INITIAL IMPACT WITH TREES, THE MAIN PORTION OF THE FUSELAGE TRAVELED ABOUT 1000 FT BEFORE COMING TO REST. NO PREIMPACT MECHANICAL PROBLEM WAS FOUND.
NTSB Probable Cause
THE PILOT'S IMPROPER INFLIGHT PLANNING AND FAILURE TO MAINTAIN PROPER ALTITUDE IN MOUNTAINOUS TERRAIN AT NIGHT.
Full Narrative
AS THE FLT WAS APCHG THE DESTN, AT NGT, THE PLT OBTAINED VECTORS FOR A DSCNT OVER MOUNTAINOUS TERRAIN. DURING THE APCH, HE CANCELLED THE IFR FLT PLAN & THE ACFT DSNDD BELOW RADAR COVERAGE. SUBSEQUENTLY, THE ACFT CRASHED IN MOUNTAINOUS TERRAIN, NORTHWEST OF THE DESTN ARPT. IMPACT OCCURRED IN A WOODED AREA AT AN ELEVATION OF ABOUT 2700 FT. THE ELT DID NOT ACTIVATE DURING THE ACDNT. A SEARCH WAS INITIATED ON 12/1/90, BUT THE ACFT & SURVIVING PASSENGER WERE NOT FND UNTIL THE NEXT DAY. THE CANADIAN ATP PLT & OTHER 4 PASSENGERS WERE FATALLY INJURED. AFTER INITIAL IMPACT WITH TREES, THE MAIN PORTION OF THE FUSELAGE TRAVELED ABOUT 1000 FT BEFORE COMING TO REST. NO PREIMPACT MECHANICAL PROBLEM WAS FOUND.
Flight
Event TypeAccident
Event Time18:41 PST
Nearest Airport0nm N
Runway0
Runway Length0
Runway Width0
Flight Plan FiledIFR
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftAero Commander 690A
Tail NumberN400N
Aircraft CategoryAir
DamageDestroyed
OperatorAero Air
Operating RulePart 91
Engines2
Engine TypeTurboprop
Engine DetailsGarrett · TPE-331 · Turboprop · 717
Seats7
People & Injuries
Injury Summary6 injuries (5 fatalities, 1 serious injury)
Fatal5
Serious1
Minor0
Uninjured0
Total6
Crew 1Age 47 · First Class
Conditions
ConditionsVMC
LightDark Night
WindCalm
Visibility10 sm
CeilingBroken clouds 1200 ft
Temperature / Dew Point0 C / 0 C
Altimeter30.00 inHg
Observation Time02:34
Weather SourceWFAC