ATA 70 | 71 | 72 - STANDARD PRACTICES, POWER PLANT, ENGINE

• These engines can produce a thrust from 21600 lb (9800 kg) to 33000 lb (14970 kg) epending on the aircraft version set by the engine data programming plug. 80% of thrust produced by fan, 20% by engine core, by pass ratio 6.2 to 1.

• We can modify Engine thrust and other parameters through ECU “Data Plug” and we cannot start engine without it.

• Extend the hod-open rods to hold the doors open at either the 40 degree or 55 degree position. Fan cowls provide protection to engine components and engine accessory box

• The forward mount carries the engine thrust, vertical and side loads. (fan frame), AFT ENG mount is on LPT (Low Pressure Turbine) frame.

• A pressure valve, which is part of the manifold, opens when the A/C airspeed reaches 200 KTS. Then ram air pressurizes the holding tanks and the accumulated fluids are discharged overboard through the drain mast.

• 100% of N1 = 5000 Rpm. 100% of N2 = 14460 Rpm.

• The engine rotors are supported by 5 bearings housed in 2 sump cavities provided by the fan and turbine frames.

• The Low Pressure or N1 rotor, supported by 3 bearings (1B, 2R, 5R).

• The High Pressure or N2 rotor, supported by 3 bearings (3B, 3R, 4R).

• The spinner rear cone accommodates the trim balance (36) screws and is mounted onto the fan disk, securing the fan blade spacers. Bolts head must face aft!

• There are 36 titanium alloy, mid-span shrouded fan blades which form the fan.

• To optimize the efficiency and the stall margin, the inlet guide vanes and the first 3 stages are variable.

• The HPT nozzle assembly uses Compressor Discharge Pressure (CDP) air for cooling purpose.

• An air cavity between the shroud/nozzle support and the combustion case directs mixed 4th and 9th stage compressor bleed (HPC) air onto the support to maintain close clearance with HPT rotor blades throughout flight operations.

• LPT nozzle segments are internally cooled by 4th stage HPC bleed air.

• The primary parameters (N1, N2, EGT, Fuel Flow) are sent directly by the ECU to the ECAM.

• During engine start the ECU is supplied with 28 VDC by the A/C network then by its own generator, mounted on the accessory gearbox, when N2 reaches 12%. (CH A and CH B are permanently operational)

• ECU automatic de-powering on the ground:

- after 5min of A/C power up.

- after 5min of engine shut down.

• Channels A and B are permanently operational. But only the channel in control, called the Active Channel, delivers output commands.(ECU select active ch at pwr up or when active ch it is faulty)

• RH side ENG to Pylon = Electrical connectors (DRY SIDE) LH side ENG to Pylon = Hydraulic and Fuel lines.

• FADEC (Full Authority Digital Engine Control) is composed by:

- ECU (Electronic Control Unit)

- HMU (Hydro-mechanical Unit)

- Peripheral components

• Primary engine parameters (N1, N2, EGT, FF) are directly sent to ECAM by ECU, Secondary engine parameters are sent to EIU (Engine Interface Unit) first and then ECAM.

• When we turn off an engine through engine master switch, Fuel HP and LP valves close, while releasing “ENG FIRE” P/B closes LP Valve only.

• Each C-DUCT has 3 hinges and 4 latches.