AOPA Pilot Magazine - November 2020 - 74

ALTHOUGH THE
to take off and land anywhere," said
Tasuku Nakai, team captain and a
University of Tokyo doctoral student.

GRAND PRIZE

HARMONY AERONAUTICS

AW
ARDED IT S

Harmony Aeronautics, which evolved
from Texas A&M University's
Advanced Vertical Flight Laboratory,
demonstrated a scale model of its Aria
at GoFly. "The big one is 500 pounds.
We did forward flight tests-it flies
beautifully. We were flying it last week
and had an accident," co-founder and
COO Farid Saemi explained. Several
components needed repair, and the
task would take several weeks.
Aria's propeller configuration,
with coaxial rotors and counterrotating blades located below the open
cabin, helps to quiet the sound of the
props-reducing it from a loud buzz to a
low-frequency hum. "Going forward we're
going to bring the rotor overhead and
enclose the person," Saemi said.
"We really want to take this design to
the next level," said Noble Benedict, assistant professor of aerospace engineering. "It
has to be small. It has to be efficient. And
you want to take off without making noise.
We want this to be really quiet."
"This thing is quiet," Saemi noted.
"Everybody is going after eVTOL but it
sounds like a swarm of angry bees. You don't
want a swarm of bees taking off from your
backyard."
"The rotor gets more efficient as it gets
bigger," explained Carl Runco. "So we took
GoFly's 8-and-a-half foot requirement and
filled it with rotor." The optimal rotor diameter for an aircraft of this size would be 10
to 15 feet, he added.
An extra 10 to 20 percent in rotor diameter makes a big difference, Hunter Denton
said. "In a helicopter it's the outer 75 percent of the rotor that produces the majority
of the lift." Having two rotors of the same
size allow for a lower tip speed, which is critical to reducing the sound's frequency. "The
higher the frequency, the louder humans
perceive the noise," he said, while lower
frequencies are perceived as quieter. "That
matters more than the number."
"We're going to try to use this as a
springboard to future development," Runco
explained. "Over the next decade we see personal flying vehicles being accepted into a
light sport category of recreational vehicles."
74 | AOPA PILOT November 2020

HAS NOT BEEN
CLEAR THE
COMPETITION HAS
ACCELERATED THE
DEVELOPMENT OF
PERSONAL EVTOL
AIRCRAFT.
Since the fly-off, Saemi said the team
members-mostly grad students-have been
catching up on their individual research.
"However, we've also been applying for
Army and Air Force small business proposals." The coronavirus pandemic has
affected Harmony's efforts, as well. "We
are a university team in Texas, so one reason why we haven't worked on hardware is
because of stay-at-home orders and university shutdowns."

200-pound person, had not flown as
of late February.
CONCEPT AIRCRAFT AIRCYCLE

Anthony Windisch has been working on his Concept Aircraft LLC's
AirCycle design for 34 years. He
sourced many components for
his unique design from home
improvement stores. The hood
ornament-yes, it has a hood ornament-was bought online through
Amazon. The Aircycle is a small
VTOL aircraft designed to transport
a single pilot beyond 20 miles, land
at unprepared locations, and exhibit
balanced control in all flight regimes.
The Aircycle hasn't flown; finding
a flight computer to control the thrusters
has been a challenge. "They haven't been
fast enough," he said. Its industrial engine
has been hopped up using go-kart customization techniques so that it produces 34
horsepower instead of 22. When it does fly,
Windisch has no idea how high his aircraft
will go. He said first flight could occur this
year, and his wife's encouraging him to do
so. "She has a million-dollar life insurance
policy [on me] and she encourages me to
flight test immediately," he laughed.

TREK AEROSPACE FK2

"We sell ducted props. That's what our
business is. We think of this as a technology demonstrator," said Jose Fierro, vice
president of operations and business development for Trek Aerospace. "We're really
agnostic about what powers the ducted
fans."
Trek showed its Version 2.4 at GoFly,
which it started building only 30 days earlier. Going from Version 2.1 to 2.4, Trek
cut weight by 12 percent; went from 10
to 12 ducted fans, increasing redundancy
and allowing the blades to turn at slower
speeds; added batteries; and made the airframe more rigid.
"With this one we ostensibly could
lose three [fans], not all on one side, and
still maintain controllability," Fierro said.
The aircraft, which is designed to carry a

GOING FORWARD

The GoFly challenge drew 854 teams comprising more than 3,800 innovators from 103
countries. Designs run the gamut from flying
cars, flying motorcycles, and hoverboards
to human-carrying drones. Some teams are
self-funded, and others have venture capital assistance.
Although the grand prize has not yet
been awarded, it's clear that the competition has accelerated the development of
technology supporting personal eVTOL aircraft. Many teams said lessons learned from
testing earlier iterations led to significant
design changes during GoFly's final phase,
and several plan revisions beyond competition requirements.
AOPA
EMAIL mike.collins@aopa.org

TEAM AEROXO, from Russia and Lativa, mocked up an iteration of its ERA Aviabike
design (facing page, top). Trek Aerospace built its FK2 to serve as a showcase for the
firm's ducted fans (right). Tesla battery packs provide power for a number of the
concepts (far right).

AOPA Pilot Magazine - November 2020

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