Bringing Sustainable Air Transport Closer - Clean Sky

7
NO X Reduction Potential (2020 Technologies, %)
Baseline: 2000 Emissions
-20
-40
-60
-70
Bringing Sustainable Air Transport Closer
Fixed Wing
Aircraft (2)
(1) Rotorcraft: Turbofan based. Diesel NO X reduction more limited
(2) Additional gains being investigated (new Clean Sky project areas)
EPNdB
-5
-10
-15
(2)
Rotorcraft (1)
Noise Reduction Potential (2020 Technologies, EPNdB)
Baseline: 2000 Emissions
-50% Perceived Noise
e Fixed Wing
Aircraft
Rotorcraft
Significant increase in benefits through
flightpath optimisation
In large commercial and regional jet
aircraft, a key design option concerns
the incorporation of the Counter
Rotating Open Rotor (CROR) engine
architecture and technology. This
design option involves an important
trade-off: signifi cantly more fuel burn
and CO 2 reductions are expected,
coupled with less progress on noise,
when compared to future turbofan
architectures. The fi gures in these
graphs assume the use of CROR on
short/medium haul aircraft. Fixed wing
aircraft fi gures represent the median
performance improvement across the
spectrum of business jets, regional
aircraft and short/medium range
commercial aircraft. Long-range
commercial aircraft are, as yet, not
included as no (integrated) concept
aircraft predictions are available.
In rotorcraft, an innovation being
investigated concerns the adoption
of Diesel engine propulsion (on
so-called light single-engine helicopters).
The Diesel engine could
deliver impressive fuel burn and CO 2
benefi ts, albeit with a penalty in NO X
performance when compared to a
future turboshaft engine. The graphs
depict the range of variance this
would imply for both CO 2 and NO X .
Note: noise reduction is measured in Effective Perceived Noise (EPNdB), and fi gures represent the average reduction per operation (take-off,
approach or fl y-past). A reduction of 10 EPNdB is widely accepted as corresponding to a halving of perceived noise in terms of the human
auditive capacity and perception. The ACARE target of ‘halving perceived noise’ thus corresponds with a fi gure in the graph of -10 EPNdB.