system that’s built in to manage the specific heat losses
that come from hybrid-electric propulsion. We’ve also
got electromagnetic screening – it’s a facility that allows
us to easily test up to 3,000V and even beyond,”
Following a similar pathway, Collins Aerospace, which is
now part of the USA’s United Technologies Corporation
has invested US$50million into building a high-power,
high voltage laboratory to design and test more electric
aircraft (MEA) systems called The Grid. Currently being
built in Rockford, Illinois, USA, The Grid is expected to
be fully operational in two years’ time and will be
25,000ft2 in size.
“The Grid is our response to the development of
aircraft like the MEA Boeing 787,” says Todd Eckstaine,
Collins Aerospace’s director of business development for
electric power systems. “We see the industry heading
towards more-electric, hybrid-electric propulsion and allelectric
“The Grid is going to be a highly flexible platform
where we’ll be able to test multiple different electric
power ratings and voltage levels.”
Collins’s current largest laboratory has 3,000
horsepower of drive stand capability and can handle
systems of up to 540V. The Grid is being designed to have
around 8,000 horsepower drive stand capability and run
up to the order of 3,000V.
“It’s a two-times step up from the integration labs
we’ve had to date. We’re putting in the square footage
and the cooling capabilities to future-proof the lab,” says
Todd Spierling, chief engineer for advanced technology,
United Technologies Advanced Projects (UTAP). “We’re
trying to build a lab to serve the industry for the next 20,
30 years, not just the next two or three.”
“We’re not just going to test electrical propulsion
systems, we will be testing all of the systems that need to
“The lab is being configured to run as one and as
separate units that can interconnect. We’ll be able to
have half a dozen
going on if that’s the most
appropriate use at a given
time and connect them
together when necessary.”
One of the first
projects to take place at The Grid will be work on the
UTAP hybrid-electric flight demonstrator, Project 804,
which will be based on a Bombardier Dash 8-100. The
goal of this project is to re-engine and fly a regional
turboprop aircraft powered by a 2MW-class hybridelectric
propulsion system. The Grid will be used to
design and test a 1MW motor, a motor controller and
battery system which will be used to assist the
demonstrator’s fuel-burning engine as part of its
hybrid-electric propulsion system.
Back in Germany, one of the first testing projects at
Airbus’s E-Aircraft Systems Test House this year will be
for the E-Fan X hybrid-electric flight demonstrator. This
project is integrating a 2MW hybrid-electric propulsion
system onto a BAE 146 aircraft. The program, which also
involves Rolls-Royce and Siemens, was launched in 2017
and aims to demonstrate technology for hybrid-electric
single aisle airliners. Its first flight is targeted for 2021.
Llewellyn says, “Its architecture is made up of several
major components including the 2MW electric motor
which will be installed under the wing, replacing the gas
turbine that powers the fan.
Q&A: DAVID ALEXANDER, DIRECTOR OF AEROSPACE
STANDARDS, SAE INTERNATIONAL
Standards organization SAE International is responsible for the
operation of the SAE Aerospace Standards program, which covers
more electric aircraft (MEA).
Q: WHY STANDARDIZE?
A: Standards help mitigate the potential for important safety
considerations from being overlooked. They also help enable
compatibilities of form, fit, and function from multiple vendors. They
also prescribe a minimum expectation. Standards record a repeatable
process or method.
Q: WILL STANDARDS STOP INNOVATION FROM HAPPENING?
A: There exists a fear that standards constrain innovation. Therefore
standards must be written in a way that does not limit innovation.
Fortunately, most standards are voluntary and the benefits outweigh
Q: WHAT STANDARDS FOR MEA ARE BEING DEVELOPED?
A: There are several trends going on in aerospace-electrification,
unmanned, autonomous flight, additive manufacturing, new propulsion
systems, greater demands for lithium batteries, high voltage, eVTOL,
simplified flight control (enabled by fly by wire), new markets, cyber
security, research in reducing noise (both subsonic and supersonic).
Q: WHEN WILL THE STANDARDS FOR MEA BE COMPLETE?
A: It depends on many factors, industry needs, aircraft type, and
mission profiles. Standards for MEA already exist today, but there are
still many more in progress. MEA range in scale and mission. For
example, large transport aircraft that are considered “more electric” are
flying today. Small fully electric airplanes are also flying. Large hybrid
electric transport airplanes are forecasted to operate around 2050, so
MEA standards will continue to evolve.
58 JUNE \\ AEROSPACETESTINGINTERNATIONAL.COM
1 // Collins Aerospace’s
The Grid laboratory will
be dedicated to testing
2 // The Grid can be
configured to run several
independent tests or one
3 // Systems for United
Technologies’ Project 804
X-Plane will be tested at