The following article was published
in the Observer
Posted on July 25, 2004
'Dreamliner' has yet to
convince skeptics it is safe
Is the world ready for jets that pop freshly baked out of an oven?
The pros and cons of Boeing's plastic Dreamliner project
If Boeing's plans for the 7E7 Dreamliner come true, air travel will
become cleaner for the environment, quieter for those living near
airports and more pleasant for passengers.
The US aircraft maker says all of these things will flow from the
unprecedented use of advanced weight-saving composites and plastics
in the 7E7 series of 200-300 passenger jets it will be producing
from late 2008.
Advanced composites are being hailed by Boeing as the "new steel"
of the 21st century.
They comprise thin yet incredibly strong sheets of carbon fibers
and other non-metallic materials glued together with epoxy resins
and baked in giant ovens or autoclaves.
The US-based plane maker says it aims to cut final assembly-time
of the jets, using large, seamless, rivet free molded parts, from
more than four weeks for metal airliners down to three days.
Although composite parts were first used by Airbus 20 years ago,
they have never been used as extensively as in the new Boeings,
with most of the fuselage, wings and tail made of the miracle materials.
But the design of the 7E7 series -- and the 62 early orders placed
by All Nippon Airways, Air New Zealand, First Choice (UK) and Blue
Panorama of Italy -- are "provisional" meaning as yet incomplete.
Many questions remain unanswered should one of them crash and burn.
Australia's National Airports Emergency Planning Committee has spent
several years working on new procedures for composite aircraft accidents
for Airservices Australia, which runs the country's major accident
response units as well as its air traffic control system.
The issue for Airservices Australia was the habit of military high-composite
aircrafts such as the B-2 stealth bomber or the Black Hawk helicopter
to turn into toxic smoke instead of a heap of metal when they crash
Also, if broken but not burning, advanced composite materials may
shatter into potentially lethal contaminants and clouds of light
but exceptionally sharp long glassy needles.
Because some of Australia's major airports are shared by both its
own air force as well as those of visiting allies, the emergency
planning committee began reviewing procedures for such accidents
well before Boeing announced the Dreamliner project early last year.
Although according to Airservices Australia, there was never any
suggestion that the new Boeings -- or even the giant Airbus A380,
which is 23 percent composite in structure -- would be banned, spokesman
Richard Dudley said: "We were just determined to understand what
different issues might arise in an accident, and do the planning
well in advance."
The concerns of the closed sessions of the planning committee in
the event of a crash were many, including whether a high proportion
of survivors and their rescue workers would die from the longer
term effects of inhaling toxic by-products and if there were any
proven procedures for effectively decontaminating people exposed
to the materials.
It seems there might not be definitive answers until after the jets
are in service, even if the worst fears of some experts prove unfounded.
Leith Higgins, director of the Fire and Emergency Services Authority
in Western Australia, has been Airservices Australia's leading adviser
on composite materials and has studied them in great detail over
the past three years.
"These materials produce horrible little fibers when they break,"
he says, noting that the needles can pass right through limbs covered
with protective clothing.
"Where they form very small particles they can be taken into the
lungs and evade the macrophages that help keep them clean from harmful
"But I am not convinced on the available research that composite
particles will prove as lethal as asbestos as some have claimed.
"The trouble with composites, and the reason for devising elaborate
emergency responses, is that no-one can say categorically that they
will not turn out to be that dangerous.
"There are still many unanswered questions."
Airservices Australia says its emergency units will drench the site
of any high composite aircraft accident with a special foam whether
or not a fire has broken out.
"The key to our approach will be to keep any particles on the ground
thus containing their spread. This will also apply to survivors
and rescue workers," he said.
"Personal protection gear resistant to the sharp particles will
be issued and closed breathing apparatus will use a molecular filter
so fine that it will trap the very fine particles that could pose
a serious risk."
The director of the Central Disaster Unit in Sydney, David Cooper,
said the policy in the event of such an accident would be to decontaminate
any survivors or emergency workers at the site before they were
admitted to emergency wards where they might otherwise endanger
staff and other patients.
On the plus side, composite engineers say the energy absorbent characteristics
of the materials will reduce trauma and improve survival rates in
a lower velocity accident such as a bad landing, taxiway collision
or even a forced landing in benign circumstances.
"Metal fuselages break open and rip at comparatively low speeds,"
one said. "Composites recoil or bounce as they absorb much of the
energy from a slow blow, and they don't catch fire as readily either."
These claims are also borne out by the amazing examples of survival
in Grand Prix Formula 1 accidents, where the vehicles today make
even more use of composites than a 7E7.
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