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NTSB Report
May 18, 1991 · Beech C23 · N6AL
Boulder, CO
Overview
Report Status
Probable Cause
Event Type
Accident
Date
May 18, 1991
Injury Outcomes
3 injuries (2 serious injuries, 1 minor injury)
Location
Boulder, CO
Aircraft
Beech C23
Tail Number
N6AL
Operator
Dakota Ridge Aviation
Injuries
Serious
Aircraft Damage
Substantial
NTSB Number
DEN91FA072
THE REAR SEAT PASSENGER SAID THE INSTRUCTOR LET THE FRONT SEAT PASSENGER MAKE THE TAKEOFF AND 'TALKED' HIM THROUGH THE PROCEDURE. SHORTLY AFTER LIFT OFF, BOTH PASSENGERS HEARD A 'WARNING BUZZER' SOUND THAT CONTINUED UNTIL GROUND IMPACT. THE INSTRUCTOR WAS SERIOUSLY INJURED AND COULD NOT RECALL ANY DETAILS OF THE ACCIDENT.
NTSB Probable Cause
INADVERTENT STALL/MUSH DUE TO THE PASSENGERS'S DELAY IN RELINQUISHING AIRCRAFT CONTROL, AND INADEQUATE SUPERVISION OF THE FLIGHT BY THE PILOT IN COMMAND. FACTORS WERE: MIXTURE NOT LEANED, AND A HIGH DENSITY ALTITUDE TAKEOFF WITH A SLIGHT QUARTERING TAILWIND.
Full Narrative
THE REAR SEAT PASSENGER SAID THE INSTRUCTOR LET THE FRONT SEAT PASSENGER MAKE THE TAKEOFF AND 'TALKED' HIM THROUGH THE PROCEDURE. SHORTLY AFTER LIFT OFF, BOTH PASSENGERS HEARD A 'WARNING BUZZER' SOUND THAT CONTINUED UNTIL GROUND IMPACT. THE INSTRUCTOR WAS SERIOUSLY INJURED AND COULD NOT RECALL ANY DETAILS OF THE ACCIDENT.
Flight
Event TypeAccident
Event Time10:50 MDT
Nearest AirportBoulder Municipal (3nm WNW)
Runway26
Runway Length4100 ft
Runway Width75 ft
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftBeech C23
Tail NumberN6AL
Aircraft CategoryAir
DamageSubstantial
OperatorDakota Ridge Aviation
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · O-360-A4G · Reciprocating · 180
Seats4
People & Injuries
Injury Summary3 injuries (2 serious injuries, 1 minor injury)
Fatal0
Serious2
Minor1
Uninjured0
Total3
Crew 1Age 23 · Second Class
Conditions
ConditionsVMC
LightDaylight
Wind130° @ 7 kt
Visibility25 sm
CeilingBroken clouds 1200 ft
Temperature / Dew Point63 F / 45 C
Altimeter30.00 inHg
Weather SourceWIT