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NTSB Report
May 5, 1991 · Robinson R22 BETA · N2360K
Ann Arbor, MI
Overview
Report Status
Probable Cause
Event Type
Accident
Date
May 5, 1991
Injury Outcomes
1 injury (1 minor injury)
Location
Ann Arbor, MI
Aircraft
Robinson R22 BETA
Tail Number
N2360K
Operator
Lutz Robert A
Injuries
Minor
Aircraft Damage
Substantial
NTSB Number
CHI91LA146
THE PLT RPRTD THAT DURING FLT, HE NOTED RPM FLUCTUATIONS & A WARNING BUZZER. HE ADJUSTED THE THROTTLE TO 100% & NOTED THAT ALL GAGES WERE 'IN THE GREEN.' HE CHECKED THE CARBURETOR (CARB) HEAT GAGE & NOTED IT WAS ONE NEEDLE WIDTH ABOVE THE YELLOW SECTION & THAT THE OUTSIDE AIR TEMP WAS 9 DEG C (48 DEG F). WITH THESE INDCNS, HE DISCOUNTED CARB ICE & DID NOT APPLY CARB HEAT. SUBSEQUENTLY, THE ENG LOST ADDITIONAL POWER BEFORE THE PLT COULD REACH THE RWY. DURING AN EMERG LANDING, THE HELICOPTER ROLLED OVER. AN EXAM & SUBSEQUENT ENG RUN REVEALED NO MECHANICAL ANOMALIES, EXCEPT THAT THE CARB AIR TEMP GAGE WAS INDICATING 4 DEG C ABOVE THE ACTUAL TEMP. TEMP & DEW POINT AT ANN ARBOR WERE 51 & 50 DEG F, RESPECTIVELY. ACCORDING TO CARB ICE CHARTS, CONDITIONS WERE CONDUCIVE TO CARB ICE.
NTSB Probable Cause
LOSS OF ENGINE POWER DUE TO CARBURETOR ICE, AND THE PILOT'S FAILURE TO USE CARBURETOR HEAT. FACTORS RELATED TO THE ACCIDENT WERE: CARBURETOR ICING CONDITIONS, AND A FALSE INDICATION FROM THE CARBURETOR AIR TEMPERATURE GAGE.
Full Narrative
THE PLT RPRTD THAT DURING FLT, HE NOTED RPM FLUCTUATIONS & A WARNING BUZZER. HE ADJUSTED THE THROTTLE TO 100% & NOTED THAT ALL GAGES WERE 'IN THE GREEN.' HE CHECKED THE CARBURETOR (CARB) HEAT GAGE & NOTED IT WAS ONE NEEDLE WIDTH ABOVE THE YELLOW SECTION & THAT THE OUTSIDE AIR TEMP WAS 9 DEG C (48 DEG F). WITH THESE INDCNS, HE DISCOUNTED CARB ICE & DID NOT APPLY CARB HEAT. SUBSEQUENTLY, THE ENG LOST ADDITIONAL POWER BEFORE THE PLT COULD REACH THE RWY. DURING AN EMERG LANDING, THE HELICOPTER ROLLED OVER. AN EXAM & SUBSEQUENT ENG RUN REVEALED NO MECHANICAL ANOMALIES, EXCEPT THAT THE CARB AIR TEMP GAGE WAS INDICATING 4 DEG C ABOVE THE ACTUAL TEMP. TEMP & DEW POINT AT ANN ARBOR WERE 51 & 50 DEG F, RESPECTIVELY. ACCORDING TO CARB ICE CHARTS, CONDITIONS WERE CONDUCIVE TO CARB ICE.
Flight
Event TypeAccident
Event Time17:38 EDT
Nearest AirportANNARBOR (0nm N)
Runway0
Flight Plan FiledUnknown
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftRobinson R22 BETA
Tail NumberN2360K
Aircraft CategoryHeli
DamageSubstantial
OperatorLutz Robert A
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · O-320-B2C · Reciprocating · 160
Seats2
People & Injuries
Injury Summary1 injury (1 minor injury)
Fatal0
Serious0
Minor1
Uninjured0
Total1
Crew 1Age 59 · Second Class
Conditions
ConditionsIMC
LightDaylight
Wind130° @ 14 kt
Visibility2 sm
CeilingOvercast 1000 ft
Temperature / Dew Point52 / 50
Altimeter29.00 inHg
Observation Time22:38
Weather SourceWFAC