wind tunnels
“We did forensics on the
parts to see exactly where
they failed and where we
expect them to fail first.”
4 // Artist’s impression of
Boom’s Overture supersonic
airliner flying at 30,000ft
5 // The XB-1’s horizontal
tail is composite with
titanium – the tail
experiences 10,000 lb of
aerodynamic force and
temperatures of more than
300˚F at supersonic speeds
AEROSPACETESTINGINTERNATIONAL.COM // SEPTEMBER 2019 25
4
5
University. “We’ve done a lot of in-house testing and
we’ve done some in partnership with NIAR,” says Scholl.
“It’s a great lab.”
Boom partner Dassault Systèmes, which produces
software for enterprise research and development, has
established an innovation laboratory at NIAR. The
22,000 square foot facility has additive manufacturing
and conventional manufacturing processes, robotic
systems and a three-dimensional immersive reality cave;
which is a room with a wrap-around screen.
“In the Dassault 3D experience platform, they have
some built-in FEA that we use, which is great for sure,”
says Scholl. Dassault’s software is called the 3D
experience platform. “They’ve got some great tools for
automating the composites lay out. I started to use those
for the XB-1 and we’re using them extensively now.”
real testament to the team they’ve been able to put
together what they pulled off,” Scholl proudly boasts.
CUSTOM OVENS
While the wind tunnel aided the development of the 350
plus aerodynamic iterations, Boom engineers conducted
composite ply strength and resin system tests among the
more than 1,000 material assessments. Both the XB-1 and
Overture aircraft will be mostly composite, with some
metallics including titanium components in the places
where excessive heating is expected on
the fuselage. The material tests were
conducted in a variety of environments –
from the very cold that the aircraft would
experience at subsonic cruise at 30,000ft
to the extreme heat which is experienced
in supersonic cruise, with temperatures
up to 350˚F, despite being at 60,000ft.
“We started doing a bunch of coupon
tests and building up to joint testing, then
to substructure testing,” says Scholl.
“We built an entire horizontal tail for
tests. We built the entire wingspan for
tests. We built a custom oven that would
take those up to 350˚F.”
Scholl’s team took the XB-1 horizontal
tail, a 19.5kg part and subjected it to more
than 10,000 lb (44.4kN) of loading at
350˚F. “You couldn’t do this just in
metallics,” he says.
“We measured strength to find out how much load it
can take before it fails. Then, when we did achieve
failure, we did forensics on the parts so we could see
exactly where they failed and where we would expect
them to fail first.”
Engineers conducted destructive testing and would
cut up the structures to see exactly what had happened
internally. Scholl says, “When it finally did fail, the part
that yielded was the titanium fitting that held it on. We
haven’t even found the limits of the composites.”
TESTING DATA IN 3D
Boom has carried out some of its work at the National
Institute for Aviation Research (NIAR) at Wichita State
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