CF34-Engine survey

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CF34-8E

Flight Operations Seminar

February 2004

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Flight Operations Support

• Established within the GE Customer and Product Support Operation to:

– Interface with customer and airplane manufacturer flight operations

– Represent their viewpoint within GE

– Provide flight operations feedback to GE

• Staffed with pilots with airline, military, flight test, training, and engineering

experience

• Specific tasks:

– Conduct engine systems/operations briefings and seminars

– Perform operations surveys

– Research engine operations questions from customers and aircraft manufacturers

– Issue and maintain engine operations documents:

• Specific operating instructions • Operations engineering bulletins

– Maintain selected airplane flight/operations manuals

– Provide pilot support to GE Flight Test Operation

– Participate in accident/incident investigations involving GE powered airplanes

Contact Information:

Walt Moeller

Technical Pilot

GE Aircraft Engines

111 Merchant Street

Cincinnati, OH 45246

Phone: (513) 552-6602

[email protected]

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Outline

• Program Overview

• Technical Features

• Operational Characteristics

• Testing

• Normal Operating Considerations

• Reduced Thrust

• Erosive FOD and Volcanic Ash

• Inclement Weather Operation

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Commercial Engines

GE and CFM engines are built at the following locations:

• Lynn, Mass: Small Commercial Turboprop and Turbo Shaft

• Durham, NC: Small and Large Commercial Turbo Fans (CF34, CF6, GE90)

• Evendale, OH: Large Commercial Turbo Fans (CFM56)

• France (Snecma): Large Commercial Turbo Fans (CFM56, CF6) CF34-1/-3/-8/-10 CT7 shaft CT7 prop T64 T700/CT7 T58 CFM56-2 CFM56-3 CFM56-5B CF6-6 CF6-50 CF6-80A CF6-80C2 CF6-80E1 GE90

Small

Large

CFM56-5A CFM56-5C CFM56-7B

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CF34 Engine Family

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CF34 Family Evolution

CF34-1A/-3A • Reduced Noise • Improved Materials • Modularity • Boroscope Ports • Containment • High/Hot Performance CF34-3A1 • Long Life Materials • New Ignition System • Serpentine Cooled

First Stage Turbine • New Low Emission

Combustor • Improved

Maintainability

CF34-3B/-3B1 • Hot Day Performance • Higher Flow

Compressor • Improved Cruise SFC • Higher Climb/Cruise

Thrust

• Improved Flat Rating TF34

USN

S-3A USAFA-10

CF34-10 • Thrust Capability to 20,000 Lbs • Growth Capability to 22,000 lbs +

Military

Service

Corporate

Service

Corporate Service

Regional Jet and

CF34-8C/D/E/C5 • 50% Thrust Increase 14,500 lbs class • Improved SFC • Flat Rated to 86°F • FADEC equipped • Reduced Parts Count

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CF34-8E

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CF34-8E Specifications

Engine parameter -8E2 -8E5 -8E5A1

Aircraft EMBRAER 170/175 EMBRAER 170/175 EMBRAER 170/175

Flat rating temp (o_C) _ISA+15 _ISA+15 _ISA+15

Normal takeoff thrust (lbs-SLS)* 12,XXX 13,170 13,800

APR thrust (lbs-SLS)* 13,000 14,200 14,200

Length (in.) 128 128 128

Weight (lbs) 2,470 2,470 2,470

Maximum diameter (in.) 52.0 52.0 52.0

Fan diameter (in.) 46.2 46.2 46.2

Fan bypass ratio 5:1 5:1 5:1

Overall pressure ratio 28:1 28:1 28:1

Compressor stages 10 10 10

HPT stages 2 2 2

LPT stages 4 4 4

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CF34-8E Propulsion System Cross Section

4 Stage Low Pressure Turbine 2 Stage High Pressure Turbine

Chevron Exhaust Nozzle 10 Stage Compressor

Accessory Gearbox Wide Chord Fan Blades

Engine control

• Full Authority Digital Engine Control (FADEC)

Spinner design (“coniptical”) optimized for inclement weather

•The low pressure system

- Single stage fan coupled to 4 stage low pressure turbine

•The high pressure system

- Variable inlet guide vane assembly - 10 stage HP compressor rotor - 5 variable stator vane assembly - Annular combustor with 18 fuel nozzles - 2 stage HP turbine

•The accessory drive system

- Power to drive accessories is extracted from HPC front shaft and mechanically transmitted through drive shaft to accessory gearbox

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CF34-8E Nacelle and Thrust Reverser

Inlet cowl

Aermacchi

Fan cowl

Aermacchi

Thrust reverser

Hurel Hispano

Aft core cowl

Hurel Hispano

EBU systems

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CF34-8E Powerplant Airflow

Primary Airflow

Secondary Airflow

Parasitic Airflow

The airflow paths are divided into primary, secondary, and parasitic. Primary is used by the core engine. Secondary is used as fan bypass and parasitic for customer and component requirements.

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CF34-8E Thrust Reverser

Innovative design of nacelle shape and transcowl deployment:

•Transcowl naturally blocks bypass duct when deployed

•No need for blocker doors

•Improved reverse thrust efficiency •Common left hand and right hand nacelle

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CF34-8E Nacelle – Left Side Access

Operability

Bleed Valve

Exhaust

Inlet & Piccolo

Tube

Inspection

Panel

FADEC & T2

Access Panel

Pressure Relief

Door

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CF34-8E Nacelle – Right Side Access

Inlet Anti Ice

Exhaust & Piccolo

Tube Inspection

Inlet &

Piccolo

Tube

Inspection

Panel

Oil Servicing

Door

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CF34-8E Engine Bearing Structure

N1 ROTOR

Single Stage Fan Rotor

Four Stage Low Pressure Turbine

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CF34-8E Engine Bearing Structure

N2 ROTOR

Ten Stage High Pressure Compressor Two Stage High Pressure Turbine #3 BALL BEARING

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• The fan case is lined with acoustic panels for noise reduction

• The fan case also serves as a blade containment system

FAN CONTAINMENT CASE

OUTLET GUIDE VANE

TIE ROD COMPRESSOR FRONT FRAME #1 BEARING #2 BEARING FAN SPEED SENSOR

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CF34-8E High Pressure Compressor Rotor

STAGE 1 – 2

BLISK STAGE 4 – 10 SPOOL

FORWARD SHAFT

STAGE 3 BLISK

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CF34-8E High Pressure Compressor Stator

• The variable inlet guide vanes and four variable stator vane stages serve to match airflow of the forward and aft compressor stages

• The variable IGVs and VSVs are controlled by the FADEC

• At low N2 speeds they are closed and move toward the open position with increasing N2 speed

• Malfunctioning or off schedule VSVs can cause stalls or slow acceleration

• Fourth stage compressor air is extracted for sump pressurization

• Sixth stage is extracted for air conditioning, nacelle anti-ice, wing anti-ice

• Tenth stage is used for air conditioning, nacelle anti-ice and wing anti-ice

VARIABLE GEOMETRY VANES FIXED STATOR VANES

INLET GUIDE VANES

STAGE 4

BLEED MANIFOLD _{BLEED MANIFOLD}STAGE 6 VARIABLE GEOMETRY

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CF34-8E Combustor

INNER LINER NOZZLE SUPPORT SWIRLER STAGE 1 HIGH PRESSURE TURBINE NOZZLE OUTER LINER

• Fuel is supplied to the combustor by 18 fuel nozzles equally spaced around its circumference • ignitors are located within the combustor at the 4

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CF34-8E High Pressure Turbine

STAGE ONE DISK STAGE ONE BLADES STAGE TWO DISK OUTER TORQUE COUPLING STAGE TWO BLADES STAGE ONE SHROUD STAGE TWO SHROUD STAGE TWO NOZZLE

• The HPT nozzle diverts combustor exit gas to the HPT rotor

• A serious effect of flight through volcanic ash is that the ash melts in the combustor then solidifies and creates a ceramic coating on the HPT nozzle vanes, Plugging cooling holes and changing the aerodynamics of the HPT nozzle area

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CF34-8E Low Pressure Turbine

STAGE 3 – 6 ROTORS LOW PRESSURE TURBINE SHAFT LOW PRESSURE TURBINE STATOR CASE STAGE 3 – 6 NOZZLES

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CF34-8E Accessory Gearbox

• The AGB is a cast two-piece housing. Drive pads allow for the mounting of the accessories on the forward and aft faces of the gear box. Intermeshed gears are located in the housing. Power is taken form the core rotor of the engine and transmitted to the engine accessories by the gear box

• The AGB provides support and drive for all mechanical accessories needed to supply the engine with fuel, lubrication and electrical power. The top of the AGB serves as the oil reservoir.

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CF34-8E Accessory Gearbox – Aft View

Starter Air Valve

Integrated Drive Generator (IDG)

Fuel pump

Starter

PMA

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CF34-8E Accessory Gearbox – Forward View

Hydraulic Pump

Lube and Scavange Pump

Oil Filter

Chip Detector

Oil Pressure Switch

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CF34-8E Engine Airflow

BLEED AIR FOR AIRCRAFT PRESSURIZING VALVE 4TH_STAGE SHUTOFF VALVE A SUMP

PRESSURIZING _PRESSURIZINGB SUMP

C SUMP PRESSURIZING

4 6 10

HIGH PRESSURE

SHUTOFF VALVE PRESSURE REGULATING SHUTOFF VALVE

•

ECS Bleed Pressures and Temperatures

•(Maximum values at ATTCS (APR) thrust)

•6th Stage Bleed •Pstatic = 153.6 psia •Temperature = 758 F •10th Stage Bleed •Pstatic = 374.3 psia •Temperature = 1064F

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CF34-8E FADEC

• Full Authority Digital Engine Control

– No mechanical connection cockpit to engine

– Analogous to “fly by wire” aircraft control system

• Consists of

– Dedicated alternator and power supplies

– Sensors for control, monitoring and feedback

– Cables and connectors

• More than just fuel control functions

– Start

– Ignition

– Variable geometry (VSV’s)

– Reverse thrust

– Fault detection

FADEC is Full Authority Digital Engine Control. It is the name given to the most recent generation of electronic engine controls currently installed on a variety of high-bypass turbofan engines. FADEC systems are more responsive, more precise, and provide more capability than the older mechanical controls. They also integrate with the aircraft on-board electronic operating and maintenance systems to a much higher degree. The FADEC enhanced engine is not only more powerful and efficient than its mechanically controlled

counterpart, it is simpler to operate, and easier to maintain.

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FADEC Control System

• Improved operational characteristics

– Reduced ITT thermal overshoot

– Full flight regime thrust management

– Uniform engine response times

– Automated starting

– Built-in thrust ratings

– Idle speed control for aircraft bleed requirements

• Improved aircraft - engine integration

– Auto-thrust system features and compatibility

– Less hysteresis

– Digital aircraft interface

– Better informed cockpit

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Ignition System

• Features

– Two independent systems per engine

• Automatically alternated every start

– Either channel can control both ignition boxes

– Ignition off when N2 >50%

– Auto relight if “flame-out” sensed

– Pilot can select continuous ignition

– Both ignitors on for all air starts

– If FADEC detects a missed light-off during a ground start attempt the

other ignitor will be energized

– Ignitors located at the 4 and 8 o’clock position on combustion case

A

Ign A

Plugs

400Hz

115V

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VSV Control

• Match airflow of Fwd/Aft compressor stages

• Electrical vs mechanical schedule

• Steady state schedules maximize efficiency

• Transient schedule improves stall margin

• Controlled by FADEC through FMU servo valves

A

B

FMU

FADEC

B

Feedback VSV actuators

VSV

Closed

N2K

Transient Schedules Steady state _Open

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CF34-8E Fuel System

• Fuel supplied by the aircraft fuel tank(s) flows to the centrifugal boost stage of the fuel pump. Upon exiting, the flow divides into two paths. One flow passes through the secondary high-pressure gear stage of the pump and then goes back to the aircraft as motive flow.

• The second flow exits the pump, passes through the fuel/oil heat exchanger and then flows to the FMU where it enters the fuel filter.

• Once filtered, the flow leaves the FMU and returns to the fuel pump where it enters the primary high-pressure gear stage.

• The flow leaves the pump and returns to the FMU. The FMU, using commands from the FADEC, meters flow to the fuel injectors through the manifold. The 18 fuel injectors deliver atomized fuel into the combustion chamber, where it mixes with compressor discharge air and is burned.

• The fuel pump provides the controlling fuel flow to operate the OBV based on commands from the FADEC

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CF34-8E Lube System Schematic

• The lubrication system provides the following functions: oil storage and delivery,

pressurization and vent, heat and

contamination removal, lubrication/protective barrier against wear and corrosion of internal components.

• Oil from the system reservoir, is pressurized by the supply element of the Lube &

Scavenge pump, sent to the filter, to the heat exchanger for cooling, and then to the engine bearings.

• The scavenge oil is removed from the sumps and the AGB by the scavenge elements of the L&S pump, flows past the chip detector, to the deaerator, and then returns to the reservoir.

• Vent air is removed from the sumps and scavenge oil, by the air/oil separator on the AGB, or the deaerator in the oil reservoir, and vented overboard through the drain mast.

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CF34-8E

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Ratings

Transients

Operating Limits

Exceedances

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Ratings Versus Thrust Limits

• Ratings

– Takeoff and MCT

– Agency certified

• Thrust limits

– MCL, MCR, for example

– Not agency certified

– Specified by aircraft/engine manufacturers

– Reflected in aircraft power management

– Basis of aircraft climb, cruise performance

– Prolong engine life (versus MCT)

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Flat Rate Concept

• All GE/CFMI engines

• Power managed for

– Constant thrust independent of ambient temperature up to

“flat rate” temperature

– Decreased thrust above flat rate temperature to maintain a

constant ITT

– Flat rate temperature defined as ISA +∆T (for example ISA

+ 15

o

_C)

• N1 schedule reflected in

– Thrust Rating Computer (TRC), Flight Management

System (FMS)

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Engine Parameters at Takeoff Thrust

I. To meet aircraft performance requirements, the engine is designed to provide a given thrust level to some “Flat Rate” Temperature (FRT). At temperature above FRT, thrust decreases and aircraft

performance is adjusted accordingly.

II. N₁for takeoff power management schedule increases with OAT (up to FRT) to maintain constant thrust. After FRT, power management N₁(and thrust) decreases.

III. ITT increases with OAT to FRT, then remains constant.

Any deviation from N₁power management will result in corresponding deviations in ITT. This applies to positive deviations of N₁(overboost) as well as to reduced thrust operation.

Thrust TAT FRT Decreasing thrust Constant thrust I. N₁ TAT FRT Decreasing thrust Constant thrust II. ITT TAT FRT Constant ITT Increasing ITT III. ITT Red Line

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Altitude Variation

Thrust

FRT

OAT

SL

Increasing altitude

N1

FRT

OAT

SL

Increasing altitude

ITT

FRT

OAT

SL

Increasing altitude

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Typical FADEC Transient Characteristics

The power management function on FADEC engines consists of controlling N₁(rather than N₂) to produce thrust requested by the thrust lever position. The FADEC uses the ambient conditions (total air temperature, total pressure and ambient pressure) and engine bleed requirements to calculate N₁based on a thrust lever position. Additionally, FADEC modulates the variable stator vanes to maximize engine efficiency during transient and steady state operations. As a result of this increased efficiency, the ITT bloom and droop are reduced.

thrust lever

angle

N

₂

ITT

N

₁

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Operating Limits

• ITT, N

₁

, N

₂

red lines

• Based on the capabilities of hot section and rotating parts

• Limits must be compatible with transient characteristics

• FADEC engines, with lesser transients, allow higher power

management with lower potential for limit exceedances

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ITT Margin

ITT TAT FRT ITT Redline Margin OATL Deterioration

ITT margin is the difference between the ITT redline and the ITT observed on a full thrust takeoff at or above flat rate temperature (FRT). The ITT margin decreases as engine components deteriorate.

At temperatures at or above FRT, ITT on a zero-margin engine will reach the ITT redline at takeoff thrust.

An engine with a negative ITT margin will reach ITT redline at some temperature less than FRT. This is called the OAT limit (OATL).

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Contributors to ITT Exceedances

• Engine deterioration

• Engine hardware damage

• Bleed air leak

• Inappropriate selection of bleed air based

on the thrust configuration

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Effect of Temperature Inversion at Takeoff

FADEC will control the engine according to the above charts. Below FRT thrust would be maintained but N1 and ITT would be higher versus no inversion. Above FRT, some loss of thrust would occur (not deemed significant by the aircraft manufacturers) in terms of aircraft performance. Thrust TAT FRT Decreasing thrust Constant thrust I. N1 TAT FRT Decreasing thrust Constant thrust II. EGT TAT FRT Constant EGT Increasing EGT III. Thrust TAT FRT Decreasing thrust Constant thrust I. Thrust TAT FRT Decreasing thrust Constant thrust I. N1 TAT FRT Decreasing thrust Constant thrust II. N1 TAT FRT Decreasing thrust Constant thrust II. EGT TAT FRT Constant EGT Increasing EGT III. EGT TAT FRT Constant EGT Increasing EGT III.

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Testing

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Overview

• A variety of development and certification tests are

conducted on GE/CFMI engines. Ground testing is

primarily accomplished by GEAE’s

Peebles Test

Operation

in Peebles, Ohio and by comparable

SNECMA facilities in France. Flight testing is

accomplished by GEAE’s

Flight Test Operation

in

Mojave, California.

This presentation summarizes some of these tests

and test facilities used.

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Crosswind Testing

• Objectives

– Demonstrate

engine

operability in

crosswinds and

tailwinds

• Location

– Peebles Test

Operation

A bank of electrically driven fans can rotate 360º around the engine to create headwind, crosswind and tailwind conditions. We look at start

characteristics with tailwinds in excess of 50 knots as well as the engine’s resistance to instability during acceleration and high static thrust operation in high crosswind conditions. Shown above is GE90 engine.

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Cold Weather Testing

• Objectives

– Demonstrate engine

operability in a heavy ice

environment for certification

and engineering evaluation

– Demonstrate a “cold” start

• Location

– Peebles Test Operation

These tests evaluate impact on hardware and operability of ice build up on non-anti-iced engine components such as fan blades, spinner and booster/HPC stators.

Ice is allowed to build up at various power settings, then shed by centrifugal force and temperature rise during engine acceleration. In another test (not shown here), an ice slab is fired into the engine to simulate the shedding of ice that was allowed to build up on the engine because of late or no actuation of inlet anti-ice. Shown above is GE90 engine.

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Icing Tests in Climatic Hangar

(CFM56-3 Upgrade)

Normally, icing tests are run at our Peebles, Ohio outdoor test facility. In this case, test stand scheduling and ambient temperature conditions precluded outdoor testing. CFM fabricated a portable version of the Peebles test set-up and shipped it to the USAF climatic hangar in Florida, where the tests were performed with the engine installed on a leased B737-300 in a temperature controlled environment. Outside temperatures were approximately 30 deg C while temperature in the hangar were in the –15 deg C range.

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Bird Ingestion Testing

• Objectives

– Evaluate impact

on engine

hardware and

operability of bird

ingestion

• Location

– Peebles Test

Operation

Large birds (up to 8 lbs.) and medium birds (up to 2 ½ lbs.) are fired into the engine while it is operating at takeoff thrust.

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Erosive FOD Testing

• Objectives

– Evaluate ingestion

and erosion

potential in a FOD

environment

• Location

– Peebles Test

Operation

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Water Ingestion Testing

• Objectives

– Demonstrate engine operability in a heavy rain environment

– Demonstrate starting with water ingestion

• Location

– Peebles Test Operation

This test simulates a worst case downpour. The engine must demonstrate satisfactory operability. Shown above is CFM56-5C engine.

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Hail Ingestion Testing

• Objective

– Demonstrate engine

operability in a heavy hail

environment . . . for

certification

• Location

– Peebles Test Operation

One half inch ice cubes are fired through air powered “guns.” The engine must demonstrate satisfactory operability.

In another test (not shown here), 1½ inch hailstones are fired into the engine at high thrust to evaluate hardware impact.

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Fan Blade-Out Testing

• Objectives

– Demonstrate effect on engine of fan blade released at takeoff thrust

• Success Criteria – No fire

– No uncontainment

– No exceedance of mount loads – Safe shutdown

• Location

– Peebles Test Operation

Shown above is CF34 engine.

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A300 Test Bed Aircraft (CF6-80C2 Installed)

This aircraft, an A300B2 leased from Airbus Industrie, was used as a flying test bed for the CF6-80C2 PMC and FADEC engines.

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A300 Test Bed Aircraft (CF6-50C2 Installed)

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B707 Test Bed Aircraft (CFM56-5B Installed)

This aircraft was used as a flying test bed for CFM56-3/-5A/-5B/-5C engines.

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B707 Test Bed Aircraft (CFM56-3 Installed)

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B747 Test Bed Aircraft (GE90 Installed)

This aircraft, a B747-100, has been used as a flying test bed for all GE and CFM56 engines since 1992, including the GE90, CFM56-7 and CF34 engines. GE believes there is no substitute for in-flight testing. This test bed allows GE to subject our new engines to very rigorous in-flight operability testing before delivery of a new engine to the aircraft manufacturer. This helps account for the outstanding operability reputation of GE and CFM56 engines relative to those of other manufacturers. This test bed was most recently used to flight test the world’s highest thrust engine, the GE90-115B (115,000 pounds of thrust). The GP7000-series (Engine Alliance) engine for the A380 will be tested on the same aircraft as will the CF34-10 regional jet engine.

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Development and Certification Tests

• Operability and Hardware Impact

• Crosswind

• Ice

– Induction icing

– Ice slab ingestion

– Natural icing (in-flight)

• Medium bird*

– Eight 1-1.5 pound birds (four 2.5 pound birds)

– Takeoff power

– Maintain thrust lever setting for 5 minutes (demonstrate

operability for 20 minutes)

– Retain 75% thrust

• Large bird*

– Four pound bird (8.0 pound bird)

– Takeoff power

– No fire

– No uncontainment

– Mount loads not exceeded

– Normal shutdown

• Water and hail ingestion

• Fan blade out

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Typical Operability Test Maneuvers Performed

• Start

– Ground

– Air

– Manual

– Auto

• Steady state operation

– High thrust

– Low thrust

• Acceleration

– Normal

– Burst

• Deceleration

– Normal

– Chop

• Bodies

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Conditions Under Which Maneuvers are

Performed

• Normal

• Crosswind

• Tailwind

• Icing

• Rain

• Hail

• Bird ingestion

• Off schedule VSV’s

• Off schedule fuel

• Suction feed

• High angle of attack

• Slow speed

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Operability Measurements

• Time (e.g. to start, accel, decel)

• ITT

• Thrust response

• Stall free

• Flameout free

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G

-G

Icing

G

-G

G

-G

G

Rain

G

F*

G,F*

-G,F*

G,F*

Hail

-G

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Normal Operating

Considerations

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Note

• If there are inconsistencies between this

presentation and the Aircraft Operations

Documents the Aircraft Operations

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CF34-8E Preflight

Inlet Area

• Ensure ramp area near inlet is free of FOD, loose snow and ice prior to engine start

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CF34-8E Preflight

Inlet

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CF34-8E Preflight

Inlet/Fan

• Check for tools, equipment, snow, ice or FOD on fan blades, spinner or in the lower inlet near the fan • Remove snow or ice with warm air instead of

de-icing fluid

• Check for damaged fan blades

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(85)

85

NOTES

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CF34-8E Preflight

T2 Sensor

(86)

86

NOTES

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CF34-8E Preflight

Cowls and Thrust Reverser in Open Position

• Cowls and thrust reverser are hinged to pylon

(87)

87

NOTES

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CF34-8E Preflight

Fan Cowl

• Difficult to see if latches are latched at standing height when close to nacelle

• Verify that all three latches are latched. Fan cowl may look secure even though two latches may be unlatched.

2 of 3 Fan cowl latches - unlatched

3 Fan cowl latches - unlatched

(88)

88

NOTES

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Loss of Fan Cowl (CF6)

We believe this incident was the result of takeoff with one or more cowl latches open.

(89)

89

NOTES

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Loss of Fan Cowl (CF6)

(90)

90

NOTES

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CF34-8E Preflight

View of Nacelle – Aft Looking Forward

Thrust Reverser latches (2) - unlatched

(91)

91

NOTES

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CF34-8E Preflight

Core Cowl – View from 6 o’clock

• Open pressure relief door may indicate a pneumatic duct separation

Core cowl latches - latched

(92)

92

NOTES

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CF34-8E Preflight

Drain Mast

• Maintenance should be requested if large puddles appear under the drain mast

(93)

93

NOTES

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Physical Hazard Areas

Minimum Idle Thrust

• At min idle thrust, the 65 mph exhaust wake danger area extends aft of the engine approximately 86 feet.

Inlet Hazard Area Includes Worst Case

20 Knot Headwind Based on 40 ft/sec Critical Velocity

with 3 ft. Contingency Factor

WARNING: AIRCRAFT MUST BE POINTED INTO WIND FOR

ACCESS TO ENGINE COMPONENTS AT GROUND IDLE

Engine Exhaust Hazard Area Velocity = 65 MPH or greater = 29.0 m/sec (95.3 ft/sec) Exhaust Hazard Area

Includes Worst Case 20 Knot Headwind with Ground Effects

26 M (86 ft) 1.1 M (3.5 ft) 1.7 M (5.7 ft) Entry Corridor .9 M (2.7 ft) Wide 2.5 M (8.3 ft)

(94)

94

NOTES

-8EFLIGHTOPS.PPT

Physical Hazard Areas

Takeoff Thrust

0 4 8 12 16 20 24 0 4 8 12 16 20 24 28 32 36 40 44 48 52 56 60 Distance from Core Nozzle Exit, Feet

Meters 0 2 4 6 8 10 12 D is tan ce f rom A ir p la ne C L , Fe ee t 0 5 4 3 2 1 Me te rs 14 16 18 6 7 A B C D E F Velocity (ft/sec) MAX = 1583 A 50 B 100 C 200 D 400 E 800 F 1500 Exhaust Velocity Contours Include Worst Case 20 Knot Headwind with Ground Effects

A B C D E F 0 2 4 6 8 10 12 14 16 0 4 8 12 16 20 24 28 32 36 40 44 48 52 56 60 Distance from Core Nozzle Exit, Feet

Meters 0 2 4 6 8 10 12 Height Above G roun d P lane , Feet 0 5 4 3 2 1 Me te rs 14 16 18

(95)

95

NOTES

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(96)

96

NOTES

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(97)

97

NOTES

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(98)

98

NOTES

-8EFLIGHTOPS.PPT

Embraer 170 Thrust Levers

• Flats (detents) at TO/GA and MAX

• Thrust reverser deployed by lifting

the idle stop lever on the thrust lever

and moving thrust lever into the

reverse position

(99)

(100)

100

NOTES

-8EFLIGHTOPS.PPT

CF34-8E Starter Operating Limits

5 minute cool-down 90 seconds 3 through 5* 10 second cool-down 90 seconds 1 & 2 Followed By Maximum Time Start Number

Starting - Ground Operation

5 minute cool-down 120 seconds 3 through 5* 10 second cool-down 120 seconds 1 & 2 Followed By Maximum Time Start Number

Starting – In-flight Operation

5 minute cool-down 30 seconds 3 through 5

*

5 minute cool-down 90 seconds 1 & 2 Followed By Maximum Time Motoring Number

Motoring – Ground or In-flight Operation

Starter Notes

• *

After 5 sequential start attempts/motorings, cycle may be repeated following a 15 minute cool-down

• For ground starts only, the maximum accumulative starter run time per start attempt is 90 seconds (motoring plus start time)

• For in-flight starts, the maximum accumulative starter run time per start attempt is 120 seconds (motoring plus start time)

(101)

101

NOTES

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CF34-8E Ground Starting

Start Sequence

1. Thrust Lever – IDLE position

2. Ignition switch – AUTO

2. Start switch – move to START then release to RUN

• FADEC controls starter air valve, ignition and fuel flow

-

Starter air valve opens when start switch moved to START

-

Ignition sequenced on at 7% N2

-

Alternate ignitor selected if no light-off in 15 seconds after fuel on

-

Ignition A (essential bus) – No dispatch message if Ignition A inop.

-

Ignition B – Short term dispatch if Ignition B inop.

-

Either FADEC channel can control each ignition exciter

-

Alternate ignition selected for every other start

-

Automatic Fuel Control

-

Fuel on at 20% N2

-

Light-off typically within 5 seconds after fuel on

-

Starter air valve closes and ignition off at approximately 50% N2

Ground Start Notes

• FADEC will prevent engine start if thrust lever is not in the idle position

• On the ground FADEC will automatically turn off ignition and fuel if a hot start or a hung start is detected

• Engine will continue to motor until the pilot manually closes starter air valve by moving STOP/START switch to STOP

• If no light off within 30 seconds of fuel on the pilot must abort start manually (STOP/START switch to STOP)

• Dry motor the engine for at least 30 seconds after aborting a start to purge the combustor of residual fuel prior to the next start attempt

(102)

102

NOTES

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CF34-8E Starting Characteristics

Normal Ground Start

(All Numerical Values Are “Typical” Not Limits)

• Light-off

- Typically within 2-4 seconds • ITT start limit - 815°C

• Oil pressure

- Must be indicated by ground idle

Light-off 460-550°C ITT at idle

FF

Time

Fuel shutoff open 450-550 pph at idle Peak ITT = 550-650°C Peak FF = 110-180 pph prior to light-off

500-650 pph after light-off light-off occurs

(103)

103

NOTES

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CF34-8E Ground Start Considerations

• START/STOP switch

– Switch must be moved from STOP to START in 30 seconds or less or FADEC will prevent engine start

– Recycle switch through STOP position for next start attempt

• Starter air pressure

–

41 – 48 psi air supply pressure required – Slower starts with lower pressure

• Ignition selection is automatic

– FADEC alternates A and B ignitors on every other start

• Cold Soaked Engine

– Oil temperature must be at least -40 °C prior to engine start

– Oil pressure peaks to full scale may occur due to high oil viscosity

– Oil pressure should decrease as the oil temperature increases

• Fan rotation

– N1 indication is absolute

– Tailwind may cause opposite fan rotation – Core airflow will gradually override tailwind

effect and eventually turn fan in correct direction

– Minimize tailwind prior to start by repositioning aircraft if practical

– With strong tailwinds consider manually dry-motoring engine (ignition switch OFF) to achieve positive, increasing N1 prior to continuing start (ignition switch AUTO).

• Starts with high residual ITT

– Expect delayed light-off if starting with residual ITT > 120°C

– FADEC will automatically dry motor until ITT is less than 120°C, then turn on ignition and fuel

(104)

104

NOTES

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CF34-8E In-Flight Starting

Air Start Envelope

• FADEC will not allow engine start if thrust lever is not in the idle position

• FADEC does NOT provide hot start, hung start or stall protection in the air

-5000 0 5000 10000 15000 20000 25000 0 50 100 150 200 250 300 350 Airspeed (kias) Alti tude ( ft )

Windmill Starter Assist

Starter Assist Required

Starter Assist or Windmill if N2 is greater than 7.2% Windmill Only if N2 is greater than 7.2%

(105)

105

NOTES

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CF34-8E In-Flight Starting

Starter Assisted Air Start

1. Thrust Lever – IDLE position

2. Ignition switch – AUTO

3. ITT must be less than 90°C for all air starts

• May have to dry motor engine if ITT > 90 °C (Ignition OFF)

4. Start switch – move to START then release to RUN

• FADEC controls starter air valve, ignition and fuel flow

-

Starter air valve opens when start switch moved to START

-

Ignition sequenced on at 7% N2

-

Both ignitors are on for all air starts

-

Automatic Fuel Control

-

Fuel on at 20% N2

-

Starter air valve closes and ignition off (auto) at approximately 50% N2

Assisted Air Start Notes

• FADEC will NOT provide hot start, hung start or stall protection in the air

• If N2 has not reached 20% after 15 seconds ignition and fuel will be turned on automatically • If no light-off within 30 seconds of initiating start

the pilot must abort start manually (STOP/START switch to STOP)

(106)

106

NOTES

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CF34-8E In-Flight Starting

Windmill Air Start

1. Thrust Lever – IDLE position

2. Ignition switch – AUTO

3. ITT must be less than 90°C for all air starts

4. Start switch – move to START then release to RUN

• FADEC controls, ignition and fuel flow

-

Ignition sequenced on at 7% N2

-

Both ignitors are on for all air starts

-

Automatic Fuel Control

-

Fuel on at 7.2% N2

-

Ignition off (switch in AUTO position) at 50% N2

Windmilling Air Start Notes

• FADEC will NOT provide hot start, hung start or stall protection in the air

• FADEC will not open starter air valve if outside the assisted air start envelope

• If N2 has not reached 7.2% after 15 seconds ignition and fuel will be turned on automatically • Increasing airspeed will increase windmilling

engine RPM

• Start attempt should be discontinued if no light-off within 30 seconds of fuel flow

(107)

107

NOTES

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CF34-8E Abnormal Starts

• Hot Start

– The indication of a hot start is an unusually fast ITT increase

after ignition.

– A start stall condition is indicated by an abnormally slow core

speed acceleration and an abnormal increase in ITT as

compared to core speed.

– The FADEC provides automatic hot start protection (fuel and

ignition off) on the ground. The FADEC will not provide

automatic hot start protection in the air.

• Hung Start

– A hung start is identified by abnormally slow acceleration after

ignition and rpm that stabilizes below idle.

– During ground starts, the FADEC will automatically turn off fuel

and ignition if a hung start is detected. The FADEC will not

provide automatic hung start protection in the air.

(108)

108

NOTES

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Taxi

• Minimize breakaway thrust

– Less than 40% N1 if possible

• Reduces FOD potential • Reduces blast hazard

• Operate (warm up) engines two minutes minimum prior to takeoff

• Reverse thrust during taxi only in emergency

• Oil pressure

– Varies with N2

– Minimum 25 psi

– May be full scale for cold soaked engine

• Should come off full-scale after required minimum 2 minute warm up time prior to takeoff

• Oil temperature

– Rise must be noted prior to takeoff

– Maximum 155°C continuous, 163°C for 15 minutes

• Oil quantity

(109)

109

NOTES

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CF34-8E Oil Pressure

• Oil pressure varies with N2

• Oil pressure less than 25 PSID is permissible for maximum of 10 seconds during “Negative G” operation

• Oil pressure below 25 PSID (other than negative-G condition) requires engine shutdown

(110)

110

NOTES

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CF34-8E Oil Quantity

• Varies inversely with engine speed

• Remains constant during steady-state operation

• Oil gulping: after engine start, oil level decreases due

to distribution within system (sumps, gearboxes and

supply scavenge lines)

• Increasing oil quantity or lack of gulping could indicate

leak in fuel/oil heat exchanger

(111)

111

NOTES

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Taxi

(Continued)

• Ground operation in icing conditions

– Anti-ice on

• Anti-ices inlet lip

– During extended operation (more than 30 minutes):

• Accelerate engines to 54% N1 and hold for 30 seconds (or to an N1 and

dwell time as high as practical, considering airport surface conditions and

congestion)

– Allows immediate shedding of fan blade and spinner ice

– De-ices stationary vanes with combination of shed ice impact,

pressure increase and temperature rise

• Perform this procedure

– Every 30 minutes

– Just prior to or in conjunction with the takeoff procedure, with

particular attention to engine parameters prior to final advance to

takeoff thrust

– Any time fan ice accumulation is suspected by perceived or

indicated fan vibration

(112)

112

NOTES

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Takeoff

• Reduced thrust takeoff if conditions permit

• Bleeds

– On/off depending on company policy/performance requirements

– Avoid bleed configuration changes at low altitudes after takeoff

• From an engine standpoint, rolling takeoff is preferred

– Less FOD potential on contaminated runways

– Inlet vortex likely if takeoff N1 set below 30 KIAS

– Less potential for engine instability or stall during crosswind/tailwind conditions

– Observe limitations per aircraft manufacturer’s operations documents

• N

₁

thrust management

– FADEC computes command N

₁

for max or reduced thrust based on FMS

inputs

– Thrust lever “stand up” at approximately 40% N1 prior to full thrust (minimizes

uneven acceleration)

– Pilot sets thrust lever to thrust set (TOGA) position for full thrust or reduced

thrust

– FADEC maintains N

₁

at command value

• FADEC will automatically reduce fan speed to compensate for ITT increase of ECS/anti-ice bleeds based on Takeoff Data Set inputs to the FMS prior to takeoff.

• Manual selection of ECS ON below 500 feet above airport altitude at high thrust levels may result in ITT rise above limits unless thrust is momentarily reduced prior to selecting ECS ON.

• Manual or automatic selection of cowl or wing anti-ice ON below 1700 feet above airport altitude at high thrust levels may result in ITT rise above limits unless thrust is momentarily reduced prior to selecting cowl or wing anti-ice ON or prior to entering icing conditions with anti-ice in auto mode.

(113)

113

NOTES

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ATTCS

(Automatic Takeoff Thrust Control System)

• Provides additional thrust on takeoff or go-around

• Enabled automatically during engine start

• Can be turned off for takeoff by pilot input on Takeoff Data Set

page on FMS

– For takeoff with ATTCS turned off, thrust increase to RSV thrust is

NOT available automatically or manually (even with thrust lever

push to MAX)

– Re-enabled automatically after takeoff phase completed

– Always available for go-around

• Windshear (caution or warning) detected

– Automatic increase to RSV thrust if ATTCS enabled for takeoff

– If ATTCS selected off for takeoff, RSV thrust is still available by

manually pushing thrust lever to the MAX position

– Automatic increase to RSV thrust is always available for

approach/go-around

• Thrust lever will stay in TOGA position if thrust increased to RSV level by automatic ATTCS activation

• Pilot must manually reduce thrust to maintain ITT within limits

(114)

114

NOTES

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CF34-8E5 ITT Operating Limits

CON 12800 (960) CON 12800 (960)

CON

GA RSV 14200 (1006/990) GA 13000 (965/949)

ON

GA

T/O-2 11700 (932/916) T/O-2 11700 (932/916)

OFF

T/O-2 RSV 13000 (965/949) T/O-2 11700 (932/916)

ON

T/O-2

T/O-1 13000 (965/949) T/O-1 13000 (965/949)

OFF

T/O-1 RSV 14200 (1006/990) T/O-1 13000 (965/949)*

ON

T/O-1

OEI

AEO

ATTCS

Thrust Mode

Thrust (lbf) and ITT Limits

* ITT Time limits

• 965°C for first 2 min. of the 5 min.

• 949°C for remainder of 5 min.

(115)

115

NOTES

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Maximum Continuous Thrust

• Intended for use during single engine conditions or

emergency situations

(116)

116

NOTES

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Climb

• No fixed detent or flat

(117)

117

NOTES

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Cruise

• Avoid unnecessary use of ignition

– Conserves ignitor plug life

• Trend monitoring

(118)

118

NOTES

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Descent

• Smooth thrust reduction

• Idle most economical

• FADEC maintains idle speed to meet bleed

demands

(119)

119

NOTES

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CF34-8E Idle Modes

• Flight Idle

– Activated when in-flight and not in the approach idle mode (see below)

– Provides minimum engine bleed pressure sufficient for ECS and anti-ice

systems

– Fan speed varies as a function of ECS bleed, and anti-ice bleed requirements

• Approach Idle

– Activated when the aircraft altitude is less than 15,000 feet, and the flaps are

down or the landing gear is down and locked

– Used in flight to enable rapid acceleration to go-around thrust

• Final Approach Idle

– Activated when: wing anti-ice is selected on, radar altitude is less than 1200

feet above landing altitude

– engine idle speed will drop slightly from flight idle to approach idle to allow

more descent profile flexibility during the final approach phase of flight

– wing anti-ice system performance is maintained by the pilot through thrust

lever modulation (cyan line on N1 indication showing minimum N1 to meet

wing anti-ice requirements)

• Idle modes only activated when thrust

lever is in the idle detent

(120)

120

NOTES

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Icing

• Cowl anti-ice system protects inlet cowl lip only

• Turn on anti-ice prior to entering icing

conditions

• If ice is inadvertently allowed to accumulate:

– Retard one engine at a time to idle before

turning A/I on

– Turn A/I on, monitor engine while increasing

thrust

(121)

121

NOTES

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Icing

(Continued)

• While in icing conditions in flight and

– N1 is less than 70% or

– If fan/spinner ice build-up is suspected (high

indicated or perceived vibration):

- Retard thrust lever towards idle, then advance to

minimum of 70% N1 for 10-30 seconds or until

vibration ceases

- Return thrust lever to position required for flight

conditions

(122)

122

NOTES

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Landing/Reversing

• Fan reversers only

• FADEC controls N1 in full reverse

– Pilot can move thrust lever(s) to MAX REVERSE detent

immediately, but thrust will be limited to idle until

reverser(s) deployed

• Modulate reverse if full thrust not needed

– Less thermal stress and mechanical loads

– Reduced FOD

• Reduce reverse thrust at 80 KIAS

• Forward idle by 60 KIAS

(123)

123

NOTES

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Reverse Thrust Effectiveness vs Airspeed

9,000 8,000 7,000 6,000 5,000 4,000 3,000 2,000 1,000 0 30 20 40 50 60 70 80 90 0 50 100 150 Knots TAS

Net

reverse

thrust

(lb/engine)

Percent N1

Training information only

Reverse thrust

737-300/CFM56-3

SL/STD day

Flaps 40

(124)

124

NOTES

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Shutdown

• Cool-down prior to shutdown to thermally stabilize

engine hot section

– Two minute cool-down after coming out of reverse

(includes normal taxi thrust lever movements)

– One minute cool-down if required - minimize N1

during reverse

– Five minute cool-down after high power ground

operation such as maximum power assurance check

– Cool-down not required for emergency shutdown

(125)

125

NOTES

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Reduced Thrust

CF34-8E

(126)

126

NOTES

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Overview

• Definitions and restrictions

• Benefits

• Severity analysis

• Performance aspects

• Process map and cause/effect chart

• Summary

(127)

127

NOTES

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Reduced Thrust Versus Derate

• Reduced thrust (Flex thrust) takeoff

– Takeoff at less than maximum takeoff thrust using the assumed

temperature method or a fixed thrust reduction

– V-speeds used protect minimum control speeds for full thrust

– Reduced thrust setting is not a limitation for the takeoff, i.e., full thrust may

be selected at any time during the takeoff

• Derated takeoff

– Takeoff at a thrust level less than maximum takeoff for which separate

limitations and performance data exist in the AFM. Corresponds to an

“alternate” thrust rating

– V-speeds used protect minimum control speeds for the derated thrust . . .

not original maximum takeoff thrust

– The derated thrust setting becomes an operating limitation for the takeoff

• On some installations derated thrust and reduced thrust can be used

together, e.g., a derated thrust can be selected and thrust further

reduced using the assumed temperature method

(128)

128

NOTES

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AC 25-13 Restrictions

• Reduced thrust setting must be at least 75% of the full thrust

rating or alternate thrust rating

• A periodic takeoff demonstration must be conducted using full

takeoff thrust. An approved maintenance procedure or engine

condition monitoring program may be used to extend the time

interval between takeoff demonstrations

• Reduced thrust takeoffs may not be performed

– On contaminated runways

• “More than 25 percent of the required field length, within the width being

used, is covered by standing water or slush more than .125 inch deep or

has an accumulation of snow or ice.”

– If anti-skid system is inoperative

– These restrictions do not apply to “derated” takeoffs

– Any other restrictions on reduced thrust or derated thrust are

imposed by the aircraft manufacturer or operator; not by AC 25-13

(129)

129

NOTES

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Typical Additional Restrictions on Reduced

Thrust Takeoffs

• Possible windshear

• Other MMEL items inoperative

• Anti-ice used for takeoff

• Takeoff with tailwind

• Performance demo “required”

Note: These are typical restrictions that are applied by individual operators. Each additional restriction should be investigated to determine whether or not it is valid.

When assessing a reduced thrust program, the operator should examine the rationale for each of the additional restrictions that might exist and eliminate restrictions where consistent with flight safety.