1. 16 PowerSource
PowerSource is pleased to feature an
interview with Mazen Badr, vice president
and general manager for PD Systems’ Power
Solutions Division. PD Systems specializes
in the development and engineering of
U.S. military power equipment. Through
Boeing and FCX Systems, PD Systems was
recently awarded a subcontract to build
and supply 110 ground power units (GPUs)
over the next five years. The 75-kW units
are powered by John Deere PowerTech Plus
4.5L engines and will be used by the U.S. Air
Force overseas to supply ground power to
military aircraft. Mazen talks about military
GPUs and why the jet-fuel compatible
John Deere engines are clearly the best
choice for the application.
PowerSource: What do people find most
interesting or surprising about PD Systems?
Mazen: PD Systems is a Service Disabled
Veteran Owned Small Business that has
the technical staff and program managers
to compete with any large business. Being
small allows us to be innovative and flexible
in our approach to satisfying the client’s
requirements. Our strength is taking
commercial-grade equipment and working
with the manufacturer to engineer it to meet
military specifications. Large companies
come to us because we are the window to
using your (jet-fuel compatible John Deere
engines) equipment in military applications.
PowerSource: Tell us about your recent
contract.
Mazen: It’s a high-profile, fast-moving
project because of who is involved in
making decisions (Boeing and the U.S. Air
Force). From the time we were awarded
the subcontract, we had an exceptionally
tight schedule to design, develop, and
have multiple customer reviews. Normally
a project like this would take two years or
more to validate, qualify, prototype, and
test, but we accomplished this in less than
eight months.
PowerSource: Give us some insight into the
development of these military GPUs.
Mazen: GPUs supply power to military
aircraft when it’s on the ground and are
used for lights, air conditioning, and aviation
system testing. These GPUs meet stringent
operational requirements, and there are
hundreds of specifications. As an example,
the GPU must operate at a temperature as
high as 140 degrees Fahrenheit and as low as
minus 40 degrees; be sound attenuated; and
be built with electromagnetic interference
(EMI) safeguards to protect the GPU. The
EMI also protects the aircraft it is servicing
from emissions the GPU may emit. The
GPU is also required to be rugged for harsh
environments encountered in military
applications including high wind, sand and
The perfect ground power
for military aircraft
Meeting stringent requirements and deadlines, PD Systems begins production of
a large fleet of John Deere-powered ground power units (GPUs) for the military
dust storms as well as loads of ice and snow
accumulating on the body of the GPU.
PowerSource: Temperature requirements
have become more stringent, correct?
Mazen: Yes, in the past, the military required
that components and controls be able to
withstand operation in temperatures ranging
from minus 25 to 125 degrees Fahrenheit
(minus 32 to 52 degrees Celsius). Now the
GPUs — and every component — must
withstand minus minus 40 to 140 degrees
Fahrenheit (minus 40 to 60 degrees Celsius).
Because heat rejection is so important, we
have to design and build a bigger cooling
system while maintaining the tight envelope
structure of the unit.
Through Boeing and FCX Systems, PD Systems was recently awarded a subcontract to build and supply 110 ground power
units to power military aircraft. The units supply power to lights, air conditioning, and aviation system testing when the
aircraft is on the ground.

2. 17PowerSource
PowerSource: What engine characteristics
were you looking for?
Mazen: The biggest task at the start of this
was to find an engine that provides enough
power to handle the client’s stringent
requirements. We analyzed, researched, and
compared all of the engines and found that
John Deere is the only engine in that size
and capacity that could run on JP8 fuel. For
military applications, that’s a requirement
without exception and a very important
characteristic. Secondly, other important
issues were availability and support: How
soon I could get the engine and how
supportive the manufacturer is to me.
Also, engine size and weight are important
characteristics for deciding which engine to
choose. John Deere engines weigh less than
other engines in this category. We also like
the engine’s ability to work at 140 degrees
Fahrenheit (60 degrees Celsius) without
derating the engine’s capacity. So the
John Deere engine met all the characteristics
we desired and led to our choosing
John Deere.
PowerSource: How would you describe the
support that you receive from John Deere?
Mazen: The support we received was
outstanding. The delivery schedule of the
engines was essential to meet the stringent
timeline imposed by the client. The engines
were delivered on or ahead of schedule!
Both John Deere and Bell Power responded
quickly. Both were also very supportive in
the technical and engineering qualifications
of the engine in making sure that we had the
right airflow and housing design, including
vents, to ensure operation at 140 degrees
Fahrenheit. We shared our design, and Bell
Power Systems was able to take our design
and perform airflow simulation to make sure
we were rejecting enough heat. That was
absolutely outstanding.
PowerSource: Bell Power Systems is supplying
a complete power unit, correct?
Mazen: Yes, they are supplying what we call
a mule — the engine, generator, and cooling
system. We ship them the cooling system and
alternator and have them build the base.
PowerSource: Is the overseas John Deere
dealer network important to your company?
Mazen: Absolutely. I located the John Deere
dealers to make sure there was support and
service available where these units are going.
I was happy and satisfied where the dealers
are located and the support our military
would receive.
PowerSource: How are the John Deere-
powered gen-sets performing?
Mazen: Very well. We haven’t had any
issue with the engine at all. The John Deere
engine is fuel-efficient and is able to work at
140-degrees Fahrenheit (60 degrees Celsius)
without modifications. We are very happy with
our decision. John Deere and Bell Power both
made the difference in making this program a
success. I would use John Deere again; it would
be my first choice for the future.
EmissionsCert. Tier3
EngineModel PowerTechPlus4045HFG85
Displacement 4.5L
RatedPower 134kW(179hp)@1800rpm
Cylinders 4
Aspiration Air-to-airaftercooled
Distributor
BellPowerSystems,LLC
Essex,Connecticut
(860)767-7502
www.bellpower.com
The 75-kW ground power units feature John Deere PowerTech Plus 4.5L engines.