CH-47D Auxiliary CH-47D Auxiliary Power UnitPower Unit

Terminal Learning Objective Terminal Learning Objective (TLO)(TLO)

ActionAction: : Describe components, operational Describe components, operational characteristics, functions, restrictions and characteristics, functions, restrictions and limitations of the CH-47D Auxiliary Power Unit limitations of the CH-47D Auxiliary Power Unit (APU)(APU)

ConditionCondition: : In a classroom, given a student In a classroom, given a student handouthandout

StandardStandard: : Correctly answer in writing, Correctly answer in writing, without reference, three of four questions, without reference, three of four questions, pertaining to Components, Operational pertaining to Components, Operational Characteristics , Limitations, Functions, and Characteristics , Limitations, Functions, and Malfunctions of the CH-47D APU, In Malfunctions of the CH-47D APU, In Accordance With (IAW) TM 1-1520-240-10 and Accordance With (IAW) TM 1-1520-240-10 and the student handoutthe student handout

Terminal Learning Objective Terminal Learning Objective (TLO) (Cont)(TLO) (Cont)

Safety RequirementsSafety Requirements: : NoneNone Risk AssessmentRisk Assessment: : LowLow Environmental ConsiderationEnvironmental Consideration: : NoneNone EvaluationEvaluation: : Each student will be Each student will be

evaluated on this block of instruction evaluated on this block of instruction during the written examination. This during the written examination. This will be a criterion type examination will be a criterion type examination requiring a requiring a GOGO on each scored unit. on each scored unit. You will have 90 minutes for the exam You will have 90 minutes for the exam

Learning Step/Activity (LSA) Learning Step/Activity (LSA) #1#1

1. Describe operational characteristics, of the 1. Describe operational characteristics, of the Auxiliary Power Unit (APU) ComponentsAuxiliary Power Unit (APU) Components

General CharacteristicsGeneral Characteristics Model T-62T-2BModel T-62T-2B Manufactured by Manufactured by

TurbomachTurbomach Consumes 90 PPHConsumes 90 PPH Rated Power 95 SHPRated Power 95 SHP Weight 74.8 W/O Weight 74.8 W/O

GeneratorGenerator Single stage centrifugal Single stage centrifugal

compressor/PTcompressor/PT Mounted at Sta. 600 Mounted at Sta. 600

Above the rampAbove the ramp

APU Mounting PointsAPU Mounting Points

Mounts:Mounts: Two forward and two rigid Two forward and two rigid links links APU to rotate downAPU to rotate down

Provide:Provide: Vertical and lateral supportVertical and lateral support

APU System ComponentsAPU System Components

APU Start Accumulator APU Start Module

Motor/Pump

Auxiliary Power Unit

APU Fuel Shutoff Valve

APU Electronic Sequence Unit

APU Fuel Boost Pump

APU Fault Relay

Master Caution Panel

Overhead Panel

APUGenerator

Solenoid Valve

APU AssemblyAPU Assembly

Learning Step/Activity Learning Step/Activity (LSA) #2(LSA) #2

1. Describe1. Describe Principles of Operational Principles of Operational for the APUfor the APU

Sections of the APUSections of the APU

Reduction Drive AssemblyPower Turbine Assembly

Air Inlet, and Compressor Assembly

Compressor SectionCompressor Section

Type:Type: Single stage centrifugal-flow Single stage centrifugal-flow (impeller) (impeller) Air drawn in through the inletAir drawn in through the inlet

Combustor AssemblyCombustor Assembly

Provides: Intake of ambient air to the Provides: Intake of ambient air to the compresscompress

Protects: APU against FOD ingestionProtects: APU against FOD ingestion

Power Turbine SectionPower Turbine Section

Type: Impeller turbine rotorType: Impeller turbine rotor Secured: Aft end of the turbine assembly Secured: Aft end of the turbine assembly

Reduction Gear AssemblyReduction Gear Assembly

Purpose:Purpose: Reduces power turbine shaft Reduces power turbine shaft rotational speedrotational speed Three mounting padThree mounting pad

APU Start AccumulatorAPU Start Accumulator

Mounted: Mounted: Sta.555 R/H Ramp Sta.555 R/H Ramp AreaArea

Purpose: Purpose: Stores Hydraulic FluidStores Hydraulic Fluid APU StartAPU Start Emergency Use:Emergency Use:

Utility Sub-SystemUtility Sub-System Indicator: Indicator: 3,0003,000 PSI PSI

APU Start ModuleAPU Start Module Located:Located:

Sta.584 R/H side Sta.584 R/H side ramp arearamp area

Directs:Directs: Signal PressureSignal Pressure APU AccumulatorAPU Accumulator

Controls:Controls: Operating Mode:Operating Mode:

APU APU Motor/PumpMotor/Pump

Indicator:Indicator: 3,000 PSI3,000 PSI

APU Motor/PumpAPU Motor/Pump

Mounted:Mounted: Forward Portion Forward Portion

APUAPU

Function:Function: MotorMotor

Drives APU Drives APU (Starting)(Starting)

PumpPump Supplies 3350 Supplies 3350

PSIPSI Engine StartersEngine Starters Utility Sub-Utility Sub-

SystemsSystems

Airframe Mounted Fuel Airframe Mounted Fuel Boost PumpBoost Pump

Type: Rotary vane pumpType: Rotary vane pump Supplies: 7−40 PSI to the APU driven Supplies: 7−40 PSI to the APU driven

fuel pumpfuel pump Energized:Energized:

APU start switch RUN positionAPU start switch RUN position

Pressure Fluid FilterPressure Fluid Filter

Type: Paper filter elementType: Paper filter element Mounted: Top of the reduction drive Mounted: Top of the reduction drive

assembly assembly

APU Fuel ControlAPU Fuel Control

Fuel ManifoldFuel Manifold

Constructed:Constructed: Metal fuel lineMetal fuel line

Six bosses equally spacedSix bosses equally spaced

Start Fuel Nozzle Start Fuel Nozzle AssemblyAssembly

Mounted:Mounted: Combustor housing at approx. 7 O’clock Combustor housing at approx. 7 O’clock positionposition

Purpose: Sprays fuel directly in front of the spark Purpose: Sprays fuel directly in front of the spark plug plug

APU Electrical SystemAPU Electrical System

Battery SwitchBattery Switch Two positionTwo position

APU SwitchAPU Switch Three positionThree position

APU GEN switchAPU GEN switch Two positionTwo position

Magnetic PickupMagnetic Pickup

Ignition Exciter BoxIgnition Exciter Box

Mounted: Upper R/H Mounted: Upper R/H side of the turbineside of the turbine

Purpose: Convert DC Purpose: Convert DC input to high energy input to high energy AC AC

Event/Time MeterEvent/Time Meter

Purpose:Purpose: Tracks starts on the rotor Tracks starts on the rotor

assembly assembly Tracks APU operational time Tracks APU operational time

APU Oil SystemAPU Oil System

Oil SumpOil Sump

Oil FilterOil FilterOil Pressure SwitchOil Pressure Switch

Manual Shutoff ValveManual Shutoff Valve

Located: Sta.540 L/H side of ramp areaLocated: Sta.540 L/H side of ramp area Purpose: Shut down the APU during an emergency Purpose: Shut down the APU during an emergency

Electronic Sequence Unit Electronic Sequence Unit (ESU)(ESU)

Located: Sta.585 L/H sideLocated: Sta.585 L/H side Purpose:Purpose:

Sequences the start procedure of the APUSequences the start procedure of the APU Continuously monitors the APU operationContinuously monitors the APU operation

Contains: Four BITE latches for fault Contains: Four BITE latches for fault

indicationsindications

BITE InformationBITE Information

New Modification (ESU)New Modification (ESU)

Learning Step/Activity Learning Step/Activity (LSA) #3(LSA) #3

1. Describe Start Procedures, 1. Describe Start Procedures, Operational Restrictions and Operational Restrictions and Emergency Procedures of the Emergency Procedures of the APUAPU

Start ProceduresStart Procedures

Start ProceduresStart Procedures

Three Positions Three Positions SwitchSwitch OffOff RunRun StartStart

Place switch to Place switch to RUNRUN for for 3-5 3-5 secondsseconds

Move switch to Move switch to STARTSTART for for 22 seconds and release seconds and release to to RUNRUN

Master Caution/Advisory Master Caution/Advisory PanelPanel

APU Operational APU Operational RestrictionRestriction

Tail in the wind!!!Tail in the wind!!!APU Exhaust

The APU shall not be started with a tail wind in excess of 25 knots

APU FireAPU Fire

APU switch – OFF.APU switch – OFF. ABORT START.ABORT START.

Pg: 9-1-22Pg: 9-1-22

Emergency Procedures

Check On LearningCheck On Learning What two components are driven by the What two components are driven by the

APU?APU? Motor/Pump and GeneratorMotor/Pump and Generator

How long should you wait before attempting How long should you wait before attempting a restart on the APU?a restart on the APU? 1 Minute1 Minute

If the APU ON caution light fails to comes If the APU ON caution light fails to comes ON, what should you do?ON, what should you do? Record the BITE information on 2408-13Record the BITE information on 2408-13

What is the maximum tailwind for starting What is the maximum tailwind for starting the APU?the APU? 25 knots 25 knots

SummarySummary

Have a nice dayHave a nice dayand and

Safe Flying!Safe Flying!