APU_Old by xiangpeng


									CH-47D Auxiliary Power
   Terminal Learning Objective (TLO)
 Action: Describe components, operational
 characteristics, functions, restrictions and limitations
 of the CH-47D Auxiliary Power Unit (APU)
 Condition:   In a classroom, given a student handout
 Standard:   Correctly answer in writing, without
 reference, three of four questions, pertaining to
 Components, Operational Characteristics ,
 Limitations, Functions, and Malfunctions of the CH-
 47D APU, In Accordance With (IAW) TM 1-1520-240-
 10 and the student handout
Terminal Learning Objective (TLO) (Cont)

   Safety Requirements: None
   Risk Assessment: Low
   Environmental Consideration: None
   Evaluation: Each student will be evaluated on
    this block of instruction during the written
    examination. This will be a criterion type
    examination requiring a GO on each scored
    unit. You will have 90 minutes for the exam
 Learning Step/Activity (LSA) #1
1. Describe operational characteristics, of the
   Auxiliary Power Unit (APU) Components
         General Characteristics
   Model T-62T-2B
   Manufactured by
   Consumes 90 PPH
   Rated Power 95 SHP
   Weight 74.8 W/O
   Single stage centrifugal
   Mounted at Sta. 600 Above
    the ramp
APU Mounting Points

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

   Provide: Vertical and lateral support
           APU System Components
APU Start Accumulator
                        APU Start Module

 Overhead                                                            Generator
                                                           Auxiliary Power Unit
                                                        APU Fuel Shutoff Valve

 Master                                         APU Electronic Sequence
               APU Fault
 Caution                                        Unit
 Panel                            APU Fuel Boost Pump
            Solenoid Valve
APU Assembly
  Learning Step/Activity (LSA) #2

1. Describe Principles of Operational for the APU
  Sections of the APU
Power Turbine Assembly
                            Reduction Drive Assembly

Air Inlet, and Compressor
          Compressor Section

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

   Provides: Intake of ambient air to the compress
   Protects: APU against FOD ingestion
    Power Turbine Section

   Type: Impeller turbine rotor
   Secured: Aft end of the turbine assembly
    Reduction Gear Assembly

   Purpose: Reduces power turbine shaft rotational speed
       Three mounting pad
APU Start Accumulator

    Mounted: Sta.555 R/H Ramp Area
    Purpose: Stores Hydraulic Fluid
        APU Start
        Emergency Use:
           Utility Sub-System

    Indicator: 3,000 PSI
                    APU Start Module
   Located:
       Sta.584 R/H side ramp

   Directs:
       Signal Pressure
       APU Accumulator

   Controls:
       Operating Mode:
          APU Motor/Pump

   Indicator:
       3,000 PSI
                 APU Motor/Pump

   Mounted:
     Forward Portion APU

   Function:
      Motor
         Drives APU
      Pump
         Supplies 3350 PSI
         Engine Starters
         Utility Sub-Systems
Airframe Mounted Fuel Boost Pump

     Type: Rotary vane pump
     Supplies: 7−40 PSI to the APU driven fuel pump
        Energized:
           APU start switch RUN position
          Pressure Fluid Filter

   Type: Paper filter element
   Mounted: Top of the reduction drive assembly
APU Fuel Control
    Fuel Manifold

   Constructed: Metal fuel line
     Six bosses equally spaced
    Start Fuel Nozzle Assembly

   Mounted: Combustor housing at approx. 7 O’clock
   Purpose: Sprays fuel directly in front of the spark plug
             APU Electrical System

   Battery Switch
      Two position

   APU Switch
      Three position

   APU GEN switch
      Two position
Magnetic Pickup
              Ignition Exciter Box

   Mounted: Upper R/H
    side of the turbine
   Purpose: Convert DC
    input to high energy AC
    Event/Time Meter

   Purpose:
       Tracks starts on the rotor assembly
       Tracks APU operational time
APU Oil System
Oil Sump
     Oil Filter
Oil Pressure Switch
         Manual Shutoff Valve

   Located: Sta.540 L/H side of ramp area
   Purpose: Shut down the APU during an emergency
     Electronic Sequence Unit (ESU)

   Located: Sta.585 L/H side
   Purpose:
      Sequences the start procedure of the APU

      Continuously monitors the APU operation

   Contains: Four BITE latches for fault indications
BITE Information
New Modification (ESU)
Learning Step/Activity (LSA) #3
1. Describe Start Procedures, Operational
Restrictions and Emergency Procedures of
the APU
Start Procedures
                Start Procedures
   Three Positions Switch
       Off
       Run
       Start
   Place switch to RUN
    for 3-5 seconds
   Move switch to START
    for 2 seconds and
    release to RUN
Master Caution/Advisory Panel
APU Operational Restriction
                     Tail in the wind!!!
APU Exhaust

 The APU shall not be
 started with a tail wind
 in excess of 25 knots
Pg: 9-1-22
                 APU Procedures
    APU switch – OFF.
                   Check On Learning
   What two components are driven by the APU?
       Motor/Pump and Generator
   How long should you wait before attempting a restart
    on the APU?
       1 Minute
   If the APU ON caution light fails to comes ON, what
    should you do?
       Record the BITE information on 2408-13
   What is the maximum tailwind for starting the APU?
       25 knots
Have a nice day
 Safe Flying!

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