1. carbon
Aeronautics: ever increasing
composites solutions
Aeronautics: ever increasing
composites solutions
Carbon fabrics help e-Go aircraft
to save 53% on weight
FeatureAeronautics
No80 April 2013 / jec composites magazine 33
E
arly in 2007, the United Kingdom’s
Civil Aviation Authority announced
a new class of aircraft, known as the
Single Seat De-Regulated (SSDR) class.
This greatly reduces the paperwork needed
to design, build and fly an aircraft, as long
as certain criteria are met.
SSDR category rules
The former Popular Flying Association
(PFA, now the Light Aircraft Associa-
tion, LAA) announced a competition for
designs in this category, including a “cheap
and easy-to-build” class and a “state-of-
the-art” class. The e-Go aircraft design
won the state-of-the-art competition and
the immediate demand for it initiated the
development process for a commercially
UK aircraft manufacturer e-Go
is about to launch a Single
Seat De-Regulated (SSDR)
aircraft. To build an aircraft
with the required weight and
mechanical performance, the
use of Spread Tow carbon fab-
rics was essential. On certain
parts, the weight saving was
as much as 53%.
Giotto Castelli, Chief Designer
& Technical Director, e-Go
Christian Borg, Communication
& Brand Director, Oxeon
Stephen Philipson, Business Development
Manager Carbon, Oxeon
By
Fig. 1: Clean aerodynamics and a compact airframe
will allow cruise in excess of 100 kts on 30 hp. This
is an early airframe assembly trial (nose undercar-
riage is a temporary one)
Oxeon AB
Företagsgatan 24
SE-504 64, Borås
Sweden
+46 33 340 18 00
contact@textreme.com
www.textreme.com

2. 53% less weight
TeXtreme® is used on selected parts of
the e-Go aircraft, and the current weight
saving amounts to 53% when compared to
conventional carbon fibre reinforcements.
Painting a TeXtreme® moulded part gives
further mass savings in that the texture of
the raw CFRP is left with fewer pinholes to
fill. Further significant weight savings are
planned on the production aircraft by re-
placing other CFRP parts with TeXtreme®.
In the case of e-Go airplanes, the main
advantage in using TeXtreme® comes from
the availability of very low areal weights
in the form of CFRP – hence its specific
properties of strength and stiffness. Mi-
crolight aircraft, particularly in the SSDR
category, tend to have low wing loading
and distributed loads that require little
structural material, especially in regions
such as wing skins, which constitute the
biggest percentage of the structural mass.
Aside from stability issues, which can be
tackled in different ways, the constraint
there is often the availability of materials
that are thin enough, and therefore light
enough, to allow an optimized design. n
More information:
www.textreme.com
available SSDR aircraft.
The founders of e-Go, Giotto Castelli and
Tony Bishop, both live in Cambridge, UK
and have a long experience working in
the aerospace sector during their careers
Giotto as designer and Tony on the busi-
ness side. Their first step after the win was
to develop the design further and test the
market.
On the design side 3D design tools were
used to ensure that the airplane would fit
together properly and weigh under 115
kg to meet the SSDR category rules. The
design was also made to meet the LSA,
ELA and microlight standards. But more
significantly, it stretches the performance
boundaries of a class having the con-
straints of SSDR, resulting in cruise speeds
almost double that of other similar aircraft.
New category of composite rein-
forcements
During the structural design, it was
evident that conventional carbon fibre
reinforcements did not allow for a more
optimized solution. For many compo-
nents, using TeXtreme® overcame this
problem.
Spread tow reinforcements (including
both spread tow fabrics and spread tow
UD tapes) are a relatively new category of
carbon
34 jec composites magazine / No80 April 2013
Fig. 3: The back of the fuselage is shown here with the mock-up engine in place. The firewall is part of the
fuselage lay-up which used a mix of 2x2 Twill and TeXtreme®. Details are very important to me and each one
needs a reason to be.
Fig. 2: Where the loads require less CFRP per area Textreme may be used. These parts are where the weight
saving is most significant. The engine cowling is shown here. It covers a large portion of the fuselage and wing
fairing area and allows plenty of access for maintenance and inspection.
composite reinforcements.
TeXtreme® Spread Tow fabrics are pro-
duced by interlacing Spread Tow tapes
of desired fibres to obtain a virtually
crimp-free fabric with straight orientation
of fibres. The result is a unique reinforce-
ment with the mechanical performance of
a cross-plied UD and the handling ease of
a fabric.