Aviation Week & Space Technology - 3 November 2014

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AviationWeek.com/awst AVIATION WEEK & SPACE TECHNOLOGY/NOVEMBER 3/10, 2014 57


petence of the Civil Aviation Adminis-
tration of China (CAAC) in assessing
airworthiness to international stan-
dards. But Avic is not assuming that
the FAA will automatically recognize a
CAAC type certificate for the MA700.
It expects to have to separately satisfy
the FAA, though Wang says the U.S. au-
thority may want to review only some
aspects of the design and verification
process. Avic sees certification as one
of its biggest challenges. Another is
gaining acceptance of its brand. So
while ATR expects to build more than
90 aircraft next year, Avic is assuming
that MA700 production will reach a
rate of just 50 a year. “We are conser-
vative,” says Wang. Perhaps he is just
being realistic in acknowledging that
demonstrating reliability and efciency
will take many years.
Pratt & Whitney Canada’s willing-
ness to improve its engine was a key
reason for its selection over Rolls-
Royce, which offered the AE2100, he
says. Compared with the PW150A that
powers the Q400, the PW150C will fea-
ture a third stage on the power turbine,
an improved low-pressure compressor
and a reduction gearbox modified for
the Dowty propeller, the engine com-
pany says. This will improve operating
economics and power reserve. A cus-
tomized cockpit interface will cut pilot
workload. Certification is due in 2018.
The engine looks powerful enough
for a stretched version of the MA700,
proposed to seat about 90, Wang says.
Avic seems not in a great rush to de-
velop the 90-seater, however, despite
turboprop operators globally calling
for such an aircraft. A proposed 50-seat
version able to fly from hot and high air-
fields may come first, Wang says.
The MA60 and MA600, current
production versions of Avic’s Y-7 re-
gional airliner, use the smaller PW127,
the same engine found on the ATR 72.
Similarly, Avic extended an MA60 and
MA600 relationship by contracting
Rockwell Collins, supplier of their cock-
pit avionics, to provide the Pro Line Fu-
sion suite for the MA700. As a result,
the MA700 will share some commonal-
ity with the Mitsubishi Aircraft MRJ;
it also uses the Pro Line Fusion suite.
The Rockwell Collins ofering attract-
ed Avic in being sophisticated but not
presenting high risk, says Wang, noting
that other airframe companies have
also chosen it. According to Rockwell
Collins, the head-up display of the Pro
Line Fusion suite ofers a key advantage


for aircraft of this size: Its image is pro-
jected from the top edge of the screen.
The traditional technology, a projector
on the ceiling, may be hard to fit into
the cockpit of a four-abreast transport.
For operators, a head-up display may
ofer more opportunities to fly in poor
weather, as authorities will allow the

pilots of aircraft with such equipment
to descend lower before seeing the run-
ways they are approaching. The CAAC
is moving to require airlines to fit head-
up displays to their aircraft, where such
equipment is available.
Rockwell Collins expects to have its
system ready for the MA700 by 2017. c

Bill Sweetman Washington

Long Lance


Unique J-20 could fit anti-access role


C


hengdu’s J-20 stealth fighter
represents the pinnacle of Chi-
na’s aerospace engineering, but
its existence and development have
posed mysteries since the unexpected
appearance of the first prototype at the
end of 2010, followed in May 2012 by
the debut of a second, similar aircraft.
The past few months, however, have
seen the first flights of a pair of signifi-
cantly diferent J-20s, identified by the
serial Nos. 2011 and 2012.
The most substantial design change
in the new aircraft appears to be that
the fuselage aft of the main landing gear
is a bit more slender, with a deeper tun-
nel in the undersurface between the
engines. The tailbooms that extend aft
of the all-moving vertical tails are lon-
ger, and the lower fixed stabilizers are
moved aft. The trailing-edge tips of the
vertical tails and canards are cropped,
and the leading-edge root extensions
are straight rather than curved.
The top line of the outer wall of the
diverterless supersonic inlet has been
drooped, and the landing gear doors
changed: The main doors now close af-
ter the gear has extended and the nose
landing gear door has been reshaped.
The F-22-style one-piece frameless
canopy on the early aircraft has given
way to a separate windshield and can-

opy, the latter
with detonation
cord to shatter
the canopy for
ejection. What appears to be a hous-
ing for an infrared search and track
system has been added below the nose,
and a missile-warning sensor fairing
installed below the aft fuselage.
The new variant aircraft appeared
slightly more than three years after
the first flight of No. 2001, so some of
the changes may reflect lessons from
flight testing. Other changes represent
a move toward a production or pre-pro-
duction design. So far, there have been
few indications as to when the J-20 will
enter service: The Pentagon, in its lat-
est annual report to Congress, says it is
unlikely to be operational before 2018.
However, the appearance of the new
aircraft tends to confirm that the de-
sign has proved sound so far; all four
prototypes are now reported to be at
Yanliang air base in Xian, the Chinese
air force’s main test site. The question
now is what role the J-20—which is not
only the first Chinese stealth fighter
but the largest tactical aircraft built in
China—will perform in the future force.
Close examination of the J-20 shows
it has no direct analogue in the West or
in Russia. The dimensions can be es-
timated accurately from open-source
satellite images, but its characteristics
are sometimes mis-assessed through a
focus on overall size. Details of avion-

The J-20
configuration
is notable, with
large in-plane
canards located
well ahead of
the main wing.

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