CompositesWorld.com 11
RTM Update
(see Fig. 1, p. 10). As the fat TFP preforms are shaped
into a wrinkle-free oval with an L-shaped cross-
section, selective stitching allows the fbers to conform
while maintaining straight alignment to carry loads,
while structural stitching assists in handling the high
loads around the frame's circumference.
Elsewhere, Aernnova Aerospace (Madrid, Spain) is
using RTM to produce the leading edge and its load-
bearing rib for the A350 XWB's horizontal tail plane
(HTP, or horizontal stabilizer). Reportedly the only Tier
1 supplier to include RTM in its bid for the design, vali-
dation, manufacture and assembly of the A350 HTP,
Aernnova used ESI Group's (Paris, France) PAM-FORM
software to simulate preforming, including fber angles
that afect permeability, and PAM-RTM software to
simulate resin injection and flling of the preform.
Together, the programs helped Aernnova eliminate
preform wrinkles, add new vent points to eliminate dry
spots and modify the RTM mold to ensure part quality
and process reproducibility.
Airbus Helicopter's Donauworth, Germany, facility
is also molding RTM structures for the A350 XWB, i.e.,
the inner structural grid for each aircraft's four pairs
of passenger doors (see "Learn More"). A WICKERT
(Landau in Pfalz, Germany) W WKP 2500 S press with
a 2500-kN closing pressure and automatic shuttle
transport is used to cure preconsolidated preforms
made from 3C-Carbon Composite Co. (Landsberg am
Lech, Germany) carbon fber fabrics injected with
Hexcel's (Stamford, CT, US) HexFlow RTM6 epoxy.
WICKERT reports a six-hour cure cycle per door.
Other parts using RTM (see "Learn More") include
the main ftting (see Fig. 2) for spoilers used on the
Airbus A330/A340 and now, refned for the A350 XWB
by FACC (Ried im Innkreis, Austria); fan blades and
the fan case for CFM International's (Cincinnati, OH,
US) LEAP jet engine; the main landing gear braces
for the Boeing 787 (now reverted to metal) made by
Aircelle's Le Havre, France, facility for Messier-Dowty
(Velizy, France) using Albany Engineered Composites
(AEC, Rochester, NH, US) 3D textile preforms; and a
variety of structures on the F-35 Lightning II fghter
built by Lockheed Martin (Ft. Worth, TX, US), GKN
Aerospace (Redditch, UK) and others.
FIG. 2 RTM'd spoiler main fittings
FACC replaced this costly forged aluminum main ftting (left) in the A330/
A340 and, now, A350 spoilers with RTM'd CFRP, cutting CTE issues and
30% of the ftting's weight (right). Source | FACC AG
Read this article online |
short.compositesworld.com/RTM-Update
Read more online about BBG's automated line for
composite window frames in "Airbus A350 to use CFRP
window frames" |
short.compositesworld.com/A350frames
Read "Tailored Fiber Placement: Besting metal in volume
production" online |
short.compositesworld.com/7QEhsvZ0
Read more online about Airbus Helicopter Donauworth's
RTM doors for the A350 in "Donauwörth as composites
pioneer" | short.compositesworld.com/DonauRTM
Read more about other RTM aircraft structures online |
short.compositesworld.com/FACCTour
short.compositesworld.com/Albany3D
short.compositesworld.com/kMtZ7sBm
short.compositesworld.com/RMCVRTM