98 AUSTRALIAN AVIATION
which with today’s technology will
weigh around two tonnes, will be
located in the forward and aft lower
hold of the aircraft.
“The power on the 3kW level is
then going to the Siemens power
distribution and the power electronics,
which is an inverter, which is going to
fi t in the nacelle,” adds Siemens’ Anton.
“This inverter is going – on the 3kW
level – to drive the Siemens SP2000
motor, which will be connected at
voltage to the fans. And this latter part is
in the nacelle.”
If electric propulsion is scalable, we
are on the verge of entering a third
generation of aviation
“Transportation has been the last
frontier for electrifi cation,” Rolls-
Royce’s Stein says. “We’ve seen
electrifi cation in road transport, in
the maritime sector, and rail. Frankly,
because the technology has not quite
been there with us, electrifi cation of
aviation has been slow to catch up.
But now with improving technology,
the start of this new era has begun.
It offers the next step change in fuel
effi ciency, noise and environmental
impact, and it now allows us to rethink
the whole layout of fl ying machines for
the fi rst time.
“The phrase used by many – ‘this
is the third generation of aviation’ – I
think is a phrase that is quite rightly
applied: the piston engine era, the jet
era, and now the electrifi cation era,”
Stein says. “We’re involved in one or two
hybrid-electric fl ight programs globally,
but this one, we believe, is going to be
the one that actually starts chartering
the frontiers of civil aviation.”
Of course, says Siemens’ Frank
Anton, “in aviation you can only
learn by fl ying. Siemens, with
Airbus, started with electric
propulsion for aircraft in 2010, and
in 2011 together, Airbus, Siemens,
and a small company called Diamond
Aircraft fl ew the very fi rst hybrid-
electric plane in the world. It was at
that time a two-seater. Now we want
to scale up, and when we started one
and a half years ago, at the beginning
of 2016, a big collaboration, Siemens
and Airbus developing different
sizes of hybrid-electric systems
for propulsion of aircraft with the
target of doing ground testing. In
this collaboration we are developing
100kW, 2MW, but we are also
developing 10MW. If you think about
a ten megawatt generator, it will use
super conductivity, and this is what we
are developing there.”
“Thanks to the extensive amount
of research we have conducted in
advanced lightweight engineering
and high-tech materials,” says Wulf
Roscher, Siemens’ project manager for
the E-Fan X, “we expect to be able to
drastically reduce the size and weight
of our drives. Although our previous
record-breaking motor achieved a
continuous performance output of
5.2kW per kilogram of motor mass, we
want to signifi cantly improve on this
in our 2MW motor.”
The E-Fan X is driven by “a triangle of
energy management”
“This confi guration of aircraft is not a
pure battery aircraft, for those not in
the aviation industry,” Rolls-Royce’s
Stein explains. “We have a gas turbine,
a Rolls-Royce gas turbine powering
a generator, and the generator
distributes the energy through a
number of fans, which will eventually
lift the aircraft in a different way than
you would today.”
“We are not betting on batteries,
we are betting on the hybrid,” says
Anton of Siemens. “Hybrid-electric
means that you have a generator
producing the power on board that
is needed for the cruise fl ight. The
batteries just add the additional power
that is needed during takeoff and
climb – that means that with today’s
Serial Hybrid architecture
Generator
Power
Electronics
Power
Distribution
Centre
Motor Power
Electronics
2MW
COCKPIT HMI* Energy Store
* Human Machine Interface
** Hybrid Electric Propulsion System
Turbofan
engine
Turbofan
engine
Turbofan
engine
FAN
FAN
FAN
FAN AE 3007 Fan & Nacelle
2MW
Generator
FAN adaptation: +
E-supervisor
HEPS**
2MW
Motor
AE 2100 Gas
Turbine
E-Fan X
The E-Fan X demonstrator
is intended to explore the
challenges of high-power
propulsion systems.AIRBUS
The humble BAe 146 is set to
provide a pioneering role in
development of the future of the
airliner.ROB FINLAYSON