Materials for Advanced Commercial Aircraft Structures

1

Materials for Advanced

Commercial Aircraft Structures

Anoush Poursartip, Ph.D., P.Eng.

Professor, Department of Materials Engineering

The University of British Columbia

Air Asia QZ8501 Dec 28, 2014

• 162 passengers

and crew

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• MH

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MH370, March 8th 2014,

227 passengers 12 crew

missing presumed dead

MH17 crashed July

17th, 2014, presumed

shot down, 283

passengers 15 crew

died

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Asiana Airlines 777

crash – San Francisco

July 6th, 2013

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6

7

9 May 2012

Iran Air 2011

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January 2011

Airbus 380

engine

explosion

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November 2010

Boeing 787

electrical fire

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Similar 777

electrical

panel fire

November 2010

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Case Study Objective, Concepts

and Content • To introduce you to engineering

– The difference between science and engineering

– The history of our profession

• To introduce you to materials engineering – All objects are made of something, and what material you

use has functional, aesthetic, cost, safety, and environmental implications

• To introduce you to an important industry: aerospace

• To introduce you to the decisions an engineer makes

12 Salisbury Cathedral, ~1250 AD

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Leonardo da Vinci, 1452-1519

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How you will be assessed

• This case-study is part of the overall

APSC150 course, directed and organized by

Professor Bhushan Gopaluni

• This case study is assessed by a single

closed book multiple choice quiz at the end of

case study.

• The quiz will be Feb 3rd, 2015 6:30-8:30 pm

CIRS 1250

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Outline • Introduction

– Airline economics

– Aircraft economics • Fuel costs – weight

• Capital costs – manufacturing

• Maintenance and repair costs

• Thus materials science – Airplane answer: composites?

» Boeing 787, Airbus 350 XWB

• History of materials

• Properties of materials

• Composites

• Weight – make it light without failing – Failure in composites

• Manufacturing – balancing material cost and production cost – Manufacturing of composites

– Manufacturing of 787

– What will Airbus do?

• Summary and conclusions

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Anatomy of a budget flight

• EasyJet flight from Luton to Nice (700 miles), average ticket price is £48.70. Lowest fare £20, highest fare £140. Full fare airline over £200

• On average flight £6,136 in fares and £545 profit. Small, but 156,000 flights and 20 million passengers. – profit margin of 8.9% after taxes

• Rule 1: fly only one type of plane. – Any airplane can fly any route

– Standardized maintenance and spare parts

• Rule 2: Drive down costs every year – economies of scale

– Better terms from insurers, suppliers; use internet

• Rule 3: Turn around aircraft as quickly as possible. – Aircraft on ground does not make money

– No seat numbers means quicker loading

– No peanuts… messy to clean up

• Rule 4: Only sell seats – nothing else… no frequent flyer programs… etc…

Guardian 20 August 2003

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Breakdown of costs – single flight • A single plane may be making eight short flights a

day

• £817: Airport charges

• £728: Administration

• £643: Crew salaries and training

• £542: Ground handling charges

• £420: Navigation

• £251: Tax

• £215: Advertising

• £101: Credit card charges

• £676: Cost of the aircraft

• £614: Fuel

• £584: Maintenance and servicing

Ticket sales: £6,136

Outgoings: £5,591

Profit: £545

Guardian 20 August 2003

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Recent Fuel Price Increases

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U.S. Gulf Coast Kerosene-Type Jet Fuel Spot Price FOB

US Dollars per Gallon

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Airplane costs

(no engines!)

Airline economics lead to

airplane economics

• Fuel:

– Make it lighter

• Cost of aircraft

– Make it cheaper to buy

• Maintenance and

servicing:

– Make it cheaper to keep

Cost in US$ millions

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21

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Developing a new airplane

• Significant undertaking

• $10-15 billion dollars upfront investment – Research and development, facilities, …

• 4-6 years leadtime

• Must sell significant number to recoup investment – Typically 300 or so airplanes

• Big stories currently: – Boeing 787 vs Airbus A350 XWB

– Airbus A380 vs Boeing 747-8i

• A major decision is what materials to use – To make airplane lighter

– To make airplane cheaper

– To make airplane more maintenable • Less checking, less repair

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Overview of materials

History

Considerations in design

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Material Categories

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History of Materials

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Materials are selected according to

need

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A need leads to a solution

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The solution

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Another Example: The need

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The solution(s)

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Processing, Manufacturing, and Assembly

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Design: Technical System as functional

layout

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Design: Technical System as a breakdown into

assemblies and components

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Design Flow Chart

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Design Flow Chart: Design Tools and

Materials Selection

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Design

Function

Process

Material Shape

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40

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Market Pull

PERFORMANCE

DRIVEN

COST

DRIVEN

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Environmental Concerns

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Environmental Concerns

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Processing Choices

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Metal Forging

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Machining

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Fastening Welding

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Cost

C CC

n

C

nm

c L

C= cost per item

Cm = material cost

Cc=Capital cost

CL= Labour cost/hour

n=batch size

n=batch rate .

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Material Properties

• General

– Cost or Relative

Cost, $/kg or $/m3

• Mechanical

– Stiffness or Modulus

of Elasticity

– Strength

– Toughness

– …

• Thermal

– Thermal conductivity

– Thermal diffusivity

– Specific heat

capacity

– Melting point

– Coefficient of thermal

expansion

– Thermal shock

resistance

• Electrical, Optical,

…

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Material Properties

• In general, there are two routes to defining properties – Fundamental properties: based on sound physics, with a

simple basis. There is good understanding, which generally leads to property values that are insensitive to test method details, and are easy to interpret: e.g. Melting Point

– Complex, derived properties: based more on need, with the physics and understanding incomplete or too complex. Therefore different test methods lead to different results and it is more difficult to interpret and compare: e.g. Bike Helmet Liner Material Performance

• So that we all get the same values for properties, we use the concept of a ‘standard’ – An agreed upon method to determine the properties or

behaviour of a material

– CSA, ASTM, DIN, ISO, ….

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Mechanical Properties:

Simple Tensile Elastic Behaviour Solids resist loads or forces by deforming

As you pull or push or twist any solid, the atoms

move relative to each other. The sum of the

resulting inter-atomic forces resists the applied

load or force.

Historically, people were interested in making

springs… A key person was Robert Hooke (1635-

1702), who was a physicist, architect, and

engineer. He used to discuss the behaviour of

springs with the great clockmaker, Thomas

Tompion (1639-1713).

Why clocks? Because of the search for an

accurate way to determine longitude (latitude is

measured by the height of the sun or stars). John

Harrison (1693-1776) finally won the Board of

Longitude competition.

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Hooke’s Law

• Hooke discovered that when we plot load (or force) vs deflection (or displacement), there is a linear relationship between the two, which is a property or characteristic of that material.

• In 1679 he wrote “Ut tensio, sic uis” which is “as the extension, so the force”.

• Hooke did not distinguish between force and stress, or between displacement and strain. We have to wait for Thomas Young (1773-1829) to realize the difference.

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Stress-Strain Curves

consider stressA

F

strain

L

For a material, if we plot stress versus strain, we get the same

curve, at least for the first portion, regardless of specimen size.

F

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Hooke’s Law: Modulus of

Elasticity

Modulus of elasticity, E Young’s Modulus

Stiffness

Failure: plasticity, fracture, …

“Strength” elastic =

recoverable=

reversible a.k.a

E

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Stress and Strain • How much stress, how much strain??

• Units of stress are Force/area, which is N/m2, otherwise known as a

Pascal, or Pa, after Blaise Pascal (1623-62).

• Stresses are typically in the order of 1-10-100 MPa (106 Pa). So what

is 10 MPa?

• 10 MPa = 10 x 106 N/m2 = 10 N/mm2.

10 mm

F= 10 x 10 x 10 = 1000 N = 1000/9.8 ~ 100 Kg

• How much strain corresponds to this? For steel, Young’s modulus or

stiffness E = 200 GPa = 200 x 109 Pa or N/m2.

Since E thus

63 5

9

10 10 110 5 10 .005%

200 10 20E

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Stress, Strain, & Toughness

• For a steel bar, of 1 metre length, a strain of 0.005%, due to a load or force of 100 kg, will lead to a deflection (or displacement, or elongation) of 0.00005 m = .05 mm = 50 microns ( about one human hair diameter!).

• The maximum value of the stress a material can take is the “strength”. For mild steel it is 200 MPa, which for our square bar 10 x 10 mm, means a failure load of 200 x 10 x 10 = 20000 N ~ 2000 kg = 2 tonnes.

• Another important property is “toughness” or the energy absorbed by the material. The work done is the area under the stress-strain curve (work done on the structure is Force x displacement).

12

d Units are P W

A L V

Work done

per unit

volume

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Materials Selection • Consider all materials available to us

– How do we compare and select?

• By considering our design needs, our functional needs

• Consider the design of a light stiff bar ( a ‘tie’)

L

F

F

Cross-section A

We want it light, so ‘objective function’

is the mass

m AL

‘The ‘constraint’ is that it be stiff, that is

not deflect too much, thus c

FL L L

E AE

where

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Design of a light stiff tie We are selecting a material to provide us with the lightest tie that is stiff

enough, so what geometric parameters are we free to vary (the ‘free

variable’)?

• The length L is fixed by the design, but we don’t care about the area

A LF

AE

2LF Fm L L

E E

Thus inserting the free variable A into the objective function m, we have

Geometry Function

Material

E

To minimize m,

maximize

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Comparison of steel and rubber for a light

stiff tie

• Steel

– 200 GPa/8 Mg/m3 =~ 25

• Rubber or Elastomer

– 0.04 GPa/1 Mg/m3 =~4 x 10-2

• Ratio = 25/ 4 x 10-2 =~ 600X

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Light Strong Tie • Consider now the design of a light strong tie

L

F

F

Cross-section A

Again, we want it light, so ‘objective

function’ is again the mass

m AL

‘The ‘constraint’ is now that it be strong

enough cF F

fF A where

Again, the free variable is A, so now

f f

Fm L L F

Geometry Function

Material

f

To minimize m,

maximize

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Comparison of steel and rubber for a light

strong tie

• Steel

– 200 MPa/8 Mg/m3 =~ 25

• Rubber or Elastomer

– 20 MPa/1 Mg/m3 =20

• Ratio = 25/ 20 =~ 1.2X

• So whereas steel makes for a much lighter stiff tie, it

does not make for a much lighter strong tie

– The difference is in the amount of deformation

• Sometimes you want more deformation, sometimes less

– A steel cable on Lions Gate bridge vs a bungee cord

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Variability • Consider a design for strength

– We choose a material of strength f, and area A,

so Ff=f x A

– We want, as stated earlier, Ff>=F

Ff F F

How big? Concept of safety factor f

f

FF

S

Why safety factor??

Variability in material

Variability in applied load

F F Ff

Extreme value statistics:

hard to guarantee failure

will never occur

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Certification

• We have already discussed the concept of a standard

– Standards are often required by the customer or by government, but otherwise they are ‘passive’

• You know of the concept of a “Professional Engineer”

– An ethical responsibility to ensure that the design meets minimum requirements

• Both the above are there to protect the public and the end-user, however, this is typically not sufficient for complicated or critical systems

• Thus for complex systems, or critical systems, there is ‘Certification’

– Approval, normally by government, of your design and decisions

• Air: FAA, JAA, Transport Canada

• Marine: US Coast Guard, DNV, Lloyds

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Composites

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Composites • Composite materials have been used

throughout history

– ancient building materials

– straw/mud huts still used today

• The human body relies on a natural composite

– bone

– hard brittle hydroxyapatite and soft protein collagen

• Wood is also a natural composite

– strong and flexible cellulose fibres are surrounded by lignin matrix

• The use of modern composites allows us to

– produce materials with unusual combinations of properties

– that cannot be met by conventional materials

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Composites • Composite materials have

been especially useful in aerospace, underwater and transport applications

• This is because composite structural materials have – low densities

– high stiffness

– can be abrasion and impact resistant

– and are not easily corroded

• What is a composite? – In general it is a structural

material made of two or more different materials

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Classification

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Composites • Many composite materials

are composed of just two phases – one termed the matrix

– the other the dispersed or reinforcing phase

• The properties of the composite are a function of – the properties of the

constituents

– their relative amounts

– and geometry of the reinforcing phase

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The Structure of Composites • Consist of two distinct phases

– matrix and a reinforcing phase

• Matrices can be

– metals (Al, Ti)

– ceramics (Al2O3, ZrO2)

– polymers (epoxy, polyester, phenolic)

• Reinforcing phases can have different shapes

– fibres, whiskers, particulates

• Technologically, fibre composites most important

– glass, carbon, Spectra (PE), Kevlar (aramid)

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Fibre composites

• Usually combinations of ceramic, polymer or glass

fibres in a polymer matrix

• Typically 40-60 % fibre by volume

• Utilize the very good properties of the fibres

• Fibre composites have a good combination of

stiffness, density and fracture toughness

• However they are often expensive

• They may be difficult to process

• Often difficult to detect damage (cracks)

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Properties of Fibres

• High strength of materials can be achieved

due to low probability of flaws in individual

fibres

• Polymers may be oriented into fibres (Spectra

or Kevlar) to utilize the strong C – C bonds of

polymer backbone

• For carbon fibres, graphite plate structure can

be oriented to take advantage of strong

bonding

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the fibre The fibre material

carbon fibre

glass fibre

aramid fibre

...

The fibre architecture

yarn

woven

braided

stitched

...

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Properties of Matrix

• The matrix binds the fibres together and protects them from

external damage

• It transmits external loads to the fibres

– the matrix itself usually carries only a small fraction of the load

• It separates the fibres and stops cracks from propagating directly

from fibre to fibre

• It supports the fibres laterally under compression loading

• It is usually has a low density to produce a composite with a low

density

• It is advantageous if the matrix has some ductility

– reinforcing phase often very stiff

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Deformation of Aligned Long Fibre

Composites • Long fibre composite materials are highly

anisotropic

• Let’s look at two extreme cases

Fibre

Matrix

Isostrain Isostress

c = m = f c = m = f

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Isostrain Analysis • Isostrain represents the best

possible properties: our composite structure has been optimised for loading direction (Upper Bound)

• Assume that under load:

c = m = f

• Total load = load

carried by fibres + load

carried by the matrix

Fc = Ff + Fm

cAc= fAf + mAm

• Therefore

c= fAf/Ac + mAm/Ac

• Since the length of the fibres = length of matrix = length of composite

c= fVf+ mVm

• Remembering that

Ec = c

Ef = f

Em = m

• We can rearrange to find the modulus of elasticity

Ec = EfVf + EmVm

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• This is the lower bound, the worst case for long fibre aligned composites

• Assume that under load:

• Strain in the composite

is given by

c = m = f

c = mVm + fVf

f

f

m

mc

VE

σV

E

σ =

E

σ

f

f

m

m

c E

V

E

V =

E

1

• Dividing by

• Therefore

mffm

fmc

VEVE

EE = E

• or

Isostress Analysis

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• Data:

– Carbon fibre

– Epoxy matrix

– Vf = 0.5

– Ef = 400 GPa,

– Em= 4 GPa GPa 202E

0.5 4 0.5 400 E

c

c

• For Isostress (loaded perpendicular to the fibres)

mffm

fmc

VEVE

EE = E

GPa 7.9= E

0.5 x 400 0.5 x 4

4 x 400 = E

c

c

• For Isostrain (loaded parallel to the fibres)

Ef

Em

0 1.0 0.50 0.25 0.75

Isostrain

Isostress

Volume fraction of fibre

Com

posite M

odulu

s

mmffc VE VE E

Example

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Strength of Composites

Effect of Orientation

• Consider loading with

the fibres perpendicular

to tensile axis (90°)

• Strength is given by the

“weakest link”

– In this case the weakest

link is the strength of the

matrix

(c)max= (m)UTS

• All other orientations fall

between the extremes

82 0° 60° 30° 90°

Effect of Orientation These are ‘macromodel’ composite laminae made of steel rods

embedded in a polyurethane rubber

They all have the same dimensions when unstressed

All are being subjected to a tensile stress

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Randomly Oriented Composites

Short Fibre

Oriented

Composite

Anisotropic

(orthotropic)

Randomly

Oriented

Composite

Isotropic in

the plane of

the fibres

GLASS CHOPPED STRAND MAT

Produced by chopping glass fiber

strands in lengths of about 50mm

and depositing these at random in

a horizontal plane

They are adhered together in a mat

with polyester binder.

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Laminar Composites

• Many composite structures and components are made by layering single sheets (called “plies”) of fibres at different orientations

• This means we can align the fibres in the direction of load

• This allows us to design for maximum strength and minimum weight!

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Laminar Composites

Unidirectional

Laminate

Cross-plied Quasi-

isotropic Laminate

The laminate

consists of 90°

and +/-45° plies

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Processing of Composites

Spray Lay-up Hand Lay-up

SCRIMP Resin Transfer Moulding

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Filament Winding

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Pultrusion

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Production of Prepreg

90

Vacuum Bagging

To

vacuum

pump

To

vacuum

gauge

Breather/

absorption fabric

Peel

Ply

Release coated

mould

Sealant

Tape

Vacuum

bag film

Release film

Perforated Laminate

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Advantages & disadvantages

• Structurally efficient

• Complex shapes with ease

• Durable and low-

maintenance

• Net shape process

• Reduced part count

– simplified assembly

– resultant savings

• Complex design

– most engineers not comfortable designing with composites

– Understanding not as advanced

• Difficult to detect damage and repair

• Higher material cost

– But dropping fairly fast

• Manufacturing of complex structures is difficult

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or

fibre + uncured resin

‘prepreg’ tape

thermoset matrix composite laminated structures

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large/complex structures are ideal

from raw material to finished

structure in one step

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10 m

5.3 m

affordability of polymer matrix

composites is primarily

achieved by making large or

complex structures

Cost/weight:

•prepreg $80/lb

•structure $400-800/lb

difference: •processing, including tooling •assembly

affordability

95

Cutting Machine

http://www.nlr.nl/documents/flyers/RTM_1994_2004_website.pdf

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Non Destructive Inspection

Ultrasound C-scan


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Resin Transfer Moulding


98

• Weight is critical on rockets, especially top section

– Many brackets, good candidates for RTM

• Baseline aluminum: 314 g

• Used aluminum tooling – no internal heating – oven heat

• Composite achieved Vf=55%

• Composite173 grammes

• 45% reduction in weight

Brackets for Ariane V

Launcher

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Composite Torque Link

• Aluminum baseline: – Machined from

forging

• Upper torque link: 175 grams

• Lower torque link: 182 grams

• Composite solution: – RTM

• Aluminum mould, heated, with elastomeric inserts

• Upper torque link: 121 grams, 31% reduction

• Lower torque link: 129 grams, 29% reduction

100

Affordable composite

landing gear

• Lower drag brace of the main

landing gear of F-16 fighter

• Maximum weight 6.2 kg (80%

of steel baseline)

• 86 J damage capability

• 70 C,85% RH capability

• High chemical resistance

• Titanium plates 2 mm thick as

protection plates for 86 J

impact by 0.5” ball

• RTM using steel moulds

101

102

Complex Structures

103

NH90 Composite

Trailing Arm

104

• 20% weight

reduction

versus steel

baseline

• Cost

reduction as

well

105

Size and Product Scaling

L.B. Ilcewicz Composites Part A 30 1999 385-393

106

How to build a metal airplane

• Aircraft manufacturing using aluminum and other metals not much changed since World War II.

– Prior to that: wood and canvas

• Aluminum aircraft consist of frames, stringers, and ribs riveted together to form a skeleton, on which an aluminum skin is riveted.

• Holes are drilled either by machine or by hand (using special jigs for positioning) and then special fasteners called rivets are used

107

• Once the structure is

finished, then the interior is

filled with wiring, fuel lines,

hydraulic lines, avionics,

etc.,.

108

Example: A380

• Wing largest ever for a commercial aircraft: – 17.7 metres from front to back where

it meets the fuselage

– 36.3 metres from fuselage to wingtip

– maximum length (single wing) is 46 metres

• Each wing has: – surface area of 845 square metres

– 25,500 different components from 52 major first-tier suppliers

http://www.cadinfo.net/editorial/A380-1.htm

109

• Each set of wings:

• 20 aluminum alloy skins

• 124 ribs (76 metallic, 48 composite materials)

• 6 aluminum alloy spars

• 314 stringers (124 for top, 190 for bottom)

• 16 leading edge, 6 trailing edge devices and 22 flying control surfaces

• 360,000 metres of wiring, piping and ducting to control the hydraulics and in turn the flaps, slats, spoilers and ailerons

• 750,000 fasteners (nuts, bolts and rivets).

• When finished, skin thickness varies between 6mm and 28mm

• Largest single panel for milling is 35 metres long.

110

• wing curvature is critical

– Normally by machining

large billet

– on A380 by 'creep forming‘

• heat and pressure to form

material to new shape

• Eight of the ten top wing

panels are creep formed

• Placed on moulds in

autoclave (42 m long, 6

metre diameter)

– Temperature and

pressure for 24 hours

111

Failure of Aircraft

The goal is to make an airplane as

light as possible without failure in

service

112

De Havilland

Comet

• de Havilland Comet entered commercial service 2 May 1952 with BOAC – first commercial jet

airliner.

– new era in civil aviation

– Significantly ahead of all other manufacturers

– 36 passengers, cruising speed of 720 km/h (450 mph), range 4000 km (2500 miles)

113

Unexplained disappearances • After just 18 months in

service, two aircraft literally disappeared within three months of each other.

• Major investigation

• Full scale testing performed: – Fuselage tested by

using water to produce pressure loading

– Hydraulic rams used to generate wing loading

– Airplane “Yoke Uncle”

– Accelerated testing: • three hour flight

simulated in ten minutes.

114

First Fatigue Failure

• At 3057 flight cycles (1221 actual and 1836 simulated) a fatigue crack produced a failure

– at rivet hole near forward port escape hatch.

– Fatigue poorly understood at that time

• Royal Navy recovered 70% of one crashed Comet from sea bed by September 1954.The reconstruction confirmed that fatigue growth in pressurized cabin was the problem.

• Redesign took until 1958, when the now Comet 4 offered the first scheduled Trans-Atlantic service

• Only 113 were made before production ceased in 1968.

• De Havilland never really recovered – Whole industry learned and changed

• First Boeing 707 prototype flew July 15, 1954

• Pan Am flew first trans-Atlantic707 service on Oct. 26, 1958

115

Aloha Airlines

& the start of

“Aging Aircraft”

• April 28, 1988, 19 year old Boeing 737 operated by Aloha Airlines lost front crown section of fuselage in full flight at 24,000 feet

• Pilot was able to land plane

• One flight attendant killed

• Severe corrosion fatigue was the problem

– Many fatigue cracks found in fuselage skin lap joints.

116

Flight 587

• American Airlines Flight 587 crashed on November 12th 2001 near Kennedy Intl. Airport, NY

• The airliner crashed into a neighborhood in Belle Harbor, New York.

• The engines and some tail components were found some distance from the main wreckage site

• 260 people killed on the aircraft

• 5 fatalities on the ground

118

What Happened?

119

Sequence of Events

• AA587 Encountered two

wake vortices from JAL 47

• Experienced a large lateral

acceleration after wake

encounter (0.1g)

• After wake encounter the

plane experienced three

strong lateral accelerations

corresponding to rudder

movements (0.3 – 0.4 g)

• Rudder data becomes

unreliable, however the

engines can still be heard

1.

2.

2.

120

NTSB Photographs

122

Air Transat 961 • 06 March 2005, Air

Transat flight 961, an Airbus A310, was going from Caribbean to Quebec at 35000 feet.

• 270 passengers and crew

• 3.45pm pilot noticed rudder (~8m high) had fallen off

123

Civil Jet Aircraft Design, www.knovel.com

124

125

126

127

128

130

131

133

134

Designing against failure for

composite structures

135

Ilcewicz FAA May 25th, 2006

136

137

138

139

140

141

142

•Bjorn Backman – Structured Research

157

Making the Boeing 787

158

159

160

161

787 Partners

162

163

Video

164

Production and Certification

165

166

167

168

169

Barrel Section Join (2007)

170

Barrel Skin Wrinkling

171

Destructive Testing

172

Limit Load Test

173

Section 11 and 12 Premature Failure

174

Design Fix

175

Ultimate Wing Test

Timeline of problems

(from Daily Telegraph) • April 26, 2004 – All Nippon Airways (ANA) becomes the launch customer for the Dreamliner, with the first of

50 planes to be delivered in 2008. By the end of 2004, total orders had reached 237. First flight scheduled

for autumn 2007.

• July 8, 2007 – first 787 unveiled at Boeing’s Everett assembly factory, with 677 orders already received.

Initial plan is for aircraft to enter commercial service in May 2008.

• Pre-launch problems

• September 5, 2007 – three-month delay to first flight announced, due to shortage of fasteners and

incomplete software.

• October 10, 2007 – second three-month delay to first flight, and six-month delay to first deliveries, due to

problems with foreign and domestic supply chain, ongoing fastener shortage and software issues.

• January 16, 2008 – third three-month delay to first flight.

• April 9, 2008 – fourth delay announced. Maiden flight rescheduled for fourth quarter of 2008, initial

deliveries put back 15 months to third quarter of 2009.

• November 4, 2008 – fifth delay, due to incorrect fastener installation and strike by Boeing staff. First flight

rescheduled for second quarter of 2009. Several airlines state intention to seek compensation for delays.

• June 15, 2009 – at the Paris Air Show, Boeing claims the 787’s maiden flight will take place within two

weeks. Eight days later it is postponed “due to a need to reinforce an area within the side-of-body section of

the aircraft”. First flight rescheduled for end of 2009.

• December 12, 2009 – Dreamliner completes high-speed taxi tests and three days later makes its maiden

flight (more than two years behind schedule). Originally to last four hours, it landed an hour early due to bad

weather. Nine-month test programme announced.

176 http://www.telegraph.co.uk/travel/travelnews/10207415/Boeing-787-

Dreamliner-a-timeline-of-problems.html


(from Daily Telegraph) • June 2010 – problems found on horizontal stabilisers of test aircraft. All planes inspected and repaired.

• August 2, 2010 – Trent 1000 engine suffers blowout at Rolls-Royce facility during ground testing. Failure

causes further delays – first delivery to ANA put back to early 2011.

• November 9, 2010 – 787 makes emergency landing after electrical fire during test flight above Texas. Flight

testing suspended the following day. Tests resume on December 23.

• January 2011 – first delivery rescheduled for third quarter of 2011, due to software and electrical updates

following in-flight fire.

• August 26, 2011 – US Federal Aviation Administration (FAA) and European Air Safety Agency certify the

787, clearing the way for deliveries.

• September 25, 2011 – first Dreamliner delivered to ANA, more than three years behind schedule.

• October 26, 2011 - first commercial flight, from Narita to Hong Kong. Tickets sold in an online auction, with

the highest bidder paying $34,000 for a seat.

• Post-launch problems

• February 6, 2012 - Boeing says it has discovered a manufacturing error that requires repairs in the fuselage

section of some Dreamliners.

• July 23, 2012 – ANA says it is having five Dreamliners repaired for a defect in their Rolls-Royce engines.

• July 28, 2012 - A 787 suffers engine failure during testing in South Carolina. US authorities announce

investigation.




(from Daily Telegraph) • September 5, 2012 - ANA aborts the take-off of a Dreamliner after what appears to be white smoke is seen

billowing from the plane's left engine, believed to be due to a glitch with the hydraulic system.

• October 4, 2012 - General Electric recommends new inspections of its GEnx engines, used on some

Boeing 747 and 787 aircraft, following the failure of an engine on a 747 operated by Air Bridge Cargo in

Shanghai on September 11.

• December 5, 2012 - The FAA orders inspections of all Dreamliners in service following reports of fuel leaks.

• January 7, 2013 - a fire breaks out on an empty Japan Airlines (JAL) Dreamliner in Boston.

• January 8, 2013 – a JAL 787 suffers fuel leak, forcing a flight from Boston to be cancelled. A crack in a

cockpit windshield grounds an ANA Dreamliner.

• January 9, 2013 – United Airlines reports problem with wiring near the main batteries on one of its six 787s.

Safety investigation launched by US National Transportation Safety Board.

• January 11, 2013 – second JAL aircraft found to have a fuel leak.

• January 13, 2013 – JAL reports fuel leak on another of its Dreamliners. Japan’s transport ministry launches

its own investigation.

• January 16, 2013 – ANA flight from Ube to Tokyo Haneda diverted after burning smell detected. Inspection

revealed a battery fire. Similar incident on a JAL 787s at Boston Logan sees all 50 Boeing 787s in service

grounded. Deliveries halted until battery problems resolved.




(from Daily Telegraph) • April 5, 2013 – final tests on new batteries completed. Flights resume on April 26.

• June 2, 2013 – JAL finds problem with air pressure sensor that detects overheating in one of its

Dreamliners.

• June 23, 2013 – United Airlines flight makes emergency landing at Houston due to problems with its brake

system.

• July 12, 2013 – fire breaks out on an empty Ethiopian Airlines 787 at Heathrow, forcing the airport to

temporarily close. Investigation finds fire was caused by lithium-manganese dioxide batteries powering an

emergency locator transmitter.

• July 18, 2013 – JAL Dreamliner flight from Boston aborted “due to a maintenance message (fuel pump)

indicator”.

• July 22, 2013 – Qatar Airways confirms grounding on a 787 due to problems with an electrical panel.

• July 24, 2013 – oven overheats on Air India flight, prompting investigation.

• July 26, 2013 – ANA finds damage to battery wiring on two Dreamliner emergency beacons, the same

device suspected of causing fire at Heathrow.

• July 27, 2013 - United Airlines also discovers problem with emergency beacon.



180

First Flight

www.787flighttest.com

Boeing 787

electrical fire

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Similar 777

electrical

panel fire

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http://www.guardian.co.uk/business/video/2011/oct/26/787-dreamliner-first-commercial-flight

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185

ELT Fire - Friday 12 July 2013

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http://nyc787.blogspot.ca/

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Summary and Conclusions

• Materials are chosen for an application based on their properties – You want to maximize performance without exceeding

certain constraints

• In aircraft, the ideal is to mimize fuel costs, aircraft costs, and maintenance/repair costs – Although aluminum has been the material of choice for

aircraft to date, the current bet by Boeing and Airbus (and other smaller aircraft manufacturers such as Bombardier, Mitsubishi, and Learjet) is that composites have finally matured to the point that they will best aluminum on all three counts

Documents

Materials for Advanced Commercial Aircraft Structures