Monday, 7 March 2016
Read; How real is the hypersonic aircraft revolution?
change: self-driving cars, drones, artificial
intelligence.
Yet the tube-shaped subsonic airliners we keep
flying on wouldn't look out of place in the 1960s.
Take, for example, the Boeing 737.
A 50-year-old design that remains one of the
workhorses of the airline industry.
And going strong: Its latest iteration, the Boeing
737 MAX is expected to enter service next year.
To be fair, although from the outside it may look
structurally similar to its earlier versions, decades
of cumulative improvements have made the airliner
of today a vastly more sophisticated, efficient and
reliable machine.
Aircraft-making is an extremely capital-intensive
activity and, given the financial and technical risks
that launching an entirely new model entails, it's
understandable that the industry prefers to keep
milking proven concepts.
But how long before the current generation of
airliners reaches its limits?
From electric propulsion to hypersonics, from NASA
to private entrepreneurs, the quest for new, truly
groundbreaking, aircraft concepts is on.
And it has the potential to forever change our idea
of air travel.
High-voltage innovation
Airbus, for example, has unveiled its future aircraft
concept.
This isn't exactly a new aircraft program, but a
depiction of what would be possible if all of the
futuristic technologies envisaged by Airbus could be
combined to create the ideal airliner.
Across the Atlantic, Boeing is also working,
together with NASA, on a number of futurist
aircraft concepts within the framework of the New
Aviation Horizons initiative .
The SUGAR program (that stands for Subsonic
Ultra Green Aircraft Research) has come up with
some truly innovative aerodynamic and propulsion
solutions.
These include an aircraft with eye-catching truss-
braced wings and an hybrid gas-electric propulsion
system fed by liquefied natural gas.
The search for new modes of propulsion is
particularly important, as aviation remains one of
the few major industries where replacing fossil fuels
remains an unresolved challenge.
Biofuels may offer a stopgap solution, as they can
be adapted to fit current engine technology and
supply infrastructure.
But it's electrically powered flight that's captured
the attention of a handful of visionaries.
It's a technology still in its infancy, but one that
benefits from the enthusiasm and resourcefulness of
entrepreneurs, not unlike the mavericks of the early
days of aviation.
By competing with each other to break the next
record, they contribute to the advancement of the
aeronautical science.
In 2015, as the long-winged Solar Impulse tried to
circumnavigate the globe on solar power, teams
were vying to be the first to cross the English
Channel on an electric-powered aircraft.
French scientist and former yachtsman Raphael
Dinelli is also preparing a solo crossing of the
Atlantic later this year on a hybrid biofuel-electric
light aircraft called Eraole.
His plane derives part of its energy from solar
power. If successful, a derivative of Eraole might
soon be serially produced for the private aviation
market.
Beyond the boom
Electric and hybrid aircraft will make flying
greener, but what about speed?
Significantly increasing the speed of current
jetliners means, inevitably, breaking the sound
barrier, which presents a whole set of challenges,
not all of them technological.
Supersonic flight isn't exactly new: The Concorde
linked both sides of the Atlantic for more than
three decades until economic and political issues led
to its retirement in 2003.
The sleek Franco-British airliner remained an
aeronautical curiosity, an experiment without
continuity or replacement.
NASA has been particularly active in developing a
new generation of more efficient, quieter supersonic
airliners to revive commercial supersonic air travel
as a viable proposition.
It's worked on such concepts with Boeing through
the New Aviation Horizons initiative, and recently
teamed up with Lockheed to research Quiet
Supersonic Technology (QueSST).
The key is to find a way to smother the sonic boom
that's produced whenever an aircraft breaks the
sound barrier.
Concorde, for example, was only allowed to make
full use of its supersonic capabilities when flying
over the ocean, thus significantly limiting the
number of markets it could serve.
A lower sonic boom may allow a future supersonic
airliner to fly routes over land, vastly increasing
potential markets.
Speed will still come at a cost, though. This why
any supersonic comeback is likely to start with
those that are most able to pay for it.
The Aerion Corporation , a Nevada-based private
aircraft manufacturer, and Airbus have already
started work on a supersonic private jet, the Aerion
AS2.
Expected to enter service early in the next decade,
it'll be able to carry up to 12 passengers at speeds
of Mach 1.6.
Hypersonic hype
Once you've broken through the sound barrier, why
not double down?
Although still closer to sci-fi than the tangible
realities of today's aviation industry, several
research organizations, from Europe to Japan, are
making inroads into hypersonic flight.
We're talking about aircraft capable of Mach 5 to
8, five to eight times faster than sound.
Realistically these revolutionary concept aircraft --
with names like Lapcat and the Hikari -- are
several decades away, but they're starting to appear
like a very feasible possibility.
One of the most ambitious concepts in the field of
hypersonics is the SpaceLiner, being developed at
the German Aerospace Center (DLR).
The SpaceLiner applies space technology to
commercial aviation in order to achieve speeds of
up to Mach 25, enough to travel from London to
Australia in under 90 minutes.
In achieving this amazing speed, the SpaceLiner
takes its passengers to the edge of space.
In fact, it's a two-stage concept, reminiscent of the,
now retired, space-shuttle.
A booster takes a civilian-carrying stage to a height
of roughly 80 kilometers, where the passenger
vehicle detaches itself to carry up to 50 passengers
to the other side of the globe.
In line with stringent safety requirements, the
passenger cabin can also double as a rescue
capsule.
Both the booster and the capsule are fully reusable,
an essential requirement to keep costs under control.
That's a principle well understood also by SpaceX
and the emerging private space industry, that has
also focused on developing reusable space vehicles.
Dr. Olga Trivailo, a researcher at the German Space
Center, DLR, says the SpaceLiner is also an
environmentally friendly concept, using a rocket
propellant mix of liquid hydrogen and liquid
oxygen that produces only water vapour upon
combustion.
Thus, hydrogen has potential as a non-fossil fuel
alternative, although first, a way would need to be
found to manage the associated higher costs
compared with kerosene, predominantly due to new
infrastructure requirements.
Dr. Martin Sippel, head of the Space Launcher
Systems Analysis department at DLR's Institute of
Space Systems in Bremen, says it would be
reasonable to expect wider use and implementation
of hydrogen propellants in the next 35 to 50 years.
The bionic cabin
While it's difficult to anticipate which one of these
different approaches to the aircraft of the future
will prevail, one thing seems sure: The air travel
experience will be transformed.
Ergonomic and lighting improvements such as those
found today on the newest airliners are just a
foretaste of what lies ahead.
Even if Airbus' vision of a "bionic smart cabin"
made of natural, smart materials that adapt to the
needs of each passenger is only partly realized, the
scope for improvement is massive.
Paradoxically, though, and because of aerodynamic
requirements, the supersonic and hypersonic aircraft
of the future may well be windowless.
The need to make up for the lack of windows, plus
the seating solutions that it opens up, is likely to
spur a new wave of innovation that'll further
redefine the in-flight experience.
The aircraft of the future will certainly take us to
our destination in a faster, greener and more
comfortable way.
What's not guaranteed is that we'll still get our
window seat.
Miquel Ros is an aviation blogger and consultant.
An economist by background, he's worked for
Flightglobal and Bloomberg. He currently covers
the airline industry through Allplane.tv and
collaborates with luxury travel website Trovel and
other online media.
Subscribe to:
Post Comments
(
Atom
)
No comments :
Post a Comment