Lunar Module Electrical Power SystemDesign ConsiderationsDesign Considerations

and Failure Modes

ObjectivesObjectivesjj

• Explain the redesign considerations

• Describe the in-flight failures

• Describe the lessons learned

OverviewOverviewFor detail - view slides under references

BatteriesBatteriesFor detail - view slides under references

Descent Battery Testing FailuresDescent Battery Testing Failures

Weld CracksWeld Cracks

Descent Battery Testing Failures Descent Battery Testing Failures ---- ContinuedContinued

Descent Batteries InDescent Batteries In--Flight FailuresFlight Failures

Apollo 13: Electrolyte LeakApollo 13: Electrolyte Leak•• Apollo 13: Electrolyte LeakApollo 13: Electrolyte Leak

•• Apollo 17: TransducerApollo 17: Transducer

Ascent Battery Testing FailuresAscent Battery Testing Failures

Ascent Battery In-Flight Failures

•• Apollo 14: UndervoltApollo 14: Undervolt

Explosive Device Battery Testing FailuresExplosive Device Battery Testing Failures

Explosive Device Battery InExplosive Device Battery In--Flight FailuresFlight Failures

•• No InNo In--Flight FailuresFlight Failures

Electrical Control AssembliesElectrical Control Assemblies

Ascent Electrical Control Assembly LocationsAscent Electrical Control Assembly Locations

Feeder Feeder SystemSystem

For detail - view slides under references

SystemSystem

Relay Junction Box &Relay Junction Box &

df ldf l

For detail - view slides under references

Deadface Relay BoxDeadface Relay Box

DC BussesDC BussesFor detail - view slides under references

AC SystemAC SystemFor detail - view slides under references

ReviewReview

• Explain the redesign considerations

• Describe the in-flight failures

• Describe the lessons learned

ReferencesReferences

Apollo Experience Report – BatteryApollo Experience Report Battery Subsystem

Apollo Experience Report Electrical WiringApollo Experience Report – Electrical Wiring Subsystem

A ll 13 Mi i R tApollo 13 Mission ReportApollo 14 Mission ReportApollo 17 Mission Report