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Aviation safety reports, made easier to study

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NTSB Report

May 18, 1983 · Hiller UH-12E · N4027L

Thermal, CA

Overview

Report Status
Preliminary report
Event Type
Accident
Date
May 18, 1983
Injury Outcomes
No injuries (1 uninjured)
Location
Thermal, CA
Aircraft
Hiller UH-12E
Tail Number
N4027L
Injuries
None
Aircraft Damage
Substantial
NTSB Number
LAX83LA236

THE PLT REPORTED THAT HE WAS APRX 1/3 OF THE WAY THRU A PROCEDURE TURN AT ABOUT 60 FT AGL, WHEN HE EXPERIENCED A PARTIAL POWER LOSS. HE COMPLETED THE TURN, LEVELED THE HELICOPTER & MOUMENTARILY REGAINED COMPLETE POWER, THEN THE ENGINE QUIT OPERATING. AN AUTOROTATIVE LANDING TO A ROAD WAS STARTED, BUT THE PLT SAW A TRUCK APPROACHING, SO HE MANEUVERED BACK TOWARD THE FIELD THAT HE HAD BEEN SPRAYING. DURING THE LANDING FLARE, THE TAIL ROTOR STRUCK THE GROUND. SUBSEQUENTLY, THE PLT LOST CONTROL OF THE HELICOPTER & IT CAME TO REST ON ITS RIGHT SIDE. DURING AN INVESTIGATION, THE AUXILIARY FUEL PUMP HAD TO BE PRIMED BEFORE THE ENG WOULD START. REPORTEDLY, A FUEL INTERUPTION TO THE PUMP COULD CAUSE IT TO LOSE ITS PRIME, & IF THIS OCCURRED DURING FLT, FUEL STARVATION WOULD OCCUR. THE PLT STATED THAT HE HAD MADE CYCLIC TURNS TO KEEP POSTITIVE G'S ON THE ROTOR SYSTEM RATHER THAN CYCLIC & PEDAL TURNS. APRX GAL OF FUEL WAS REMAINING.

Full Narrative

THE PLT REPORTED THAT HE WAS APRX 1/3 OF THE WAY THRU A PROCEDURE TURN AT ABOUT 60 FT AGL, WHEN HE EXPERIENCED A PARTIAL POWER LOSS. HE COMPLETED THE TURN, LEVELED THE HELICOPTER & MOUMENTARILY REGAINED COMPLETE POWER, THEN THE ENGINE QUIT OPERATING. AN AUTOROTATIVE LANDING TO A ROAD WAS STARTED, BUT THE PLT SAW A TRUCK APPROACHING, SO HE MANEUVERED BACK TOWARD THE FIELD THAT HE HAD BEEN SPRAYING. DURING THE LANDING FLARE, THE TAIL ROTOR STRUCK THE GROUND. SUBSEQUENTLY, THE PLT LOST CONTROL OF THE HELICOPTER & IT CAME TO REST ON ITS RIGHT SIDE. DURING AN INVESTIGATION, THE AUXILIARY FUEL PUMP HAD TO BE PRIMED BEFORE THE ENG WOULD START. REPORTEDLY, A FUEL INTERUPTION TO THE PUMP COULD CAUSE IT TO LOSE ITS PRIME, & IF THIS OCCURRED DURING FLT, FUEL STARVATION WOULD OCCUR. THE PLT STATED THAT HE HAD MADE CYCLIC TURNS TO KEEP POSTITIVE G'S ON THE ROTOR SYSTEM RATHER THAN CYCLIC & PEDAL TURNS. APRX GAL OF FUEL WAS REMAINING.

Flight

Event TypeAccident
Event Time11:00 PDT
Nearest Airport0nm N
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo

Aircraft

AircraftHiller UH-12E
Tail NumberN4027L
Aircraft CategoryHeli
DamageSubstantial
Operating RulePart 137
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · VO540-C2A · Reciprocating · 305
Seats3

People & Injuries

Injury SummaryNo injuries (1 uninjured)
Fatal0
Serious0
Minor0
Uninjured1
Total1
Crew 1Age 43 · Second Class

Conditions

ConditionsVMC
LightDaylight
Wind240° @ 5 kt
Visibility50 sm
CeilingNone
Temperature / Dew Point0 C
Altimeter29.00 inHg
Weather SourceWFAC

Appendix: Source Data