March 3, 2021
Potential Military Roles for Supersonic Transports
A new generation of supersonic (faster than the speed of
Figure 1. Aerion AS2
sound in level flight, also called Mach 1) passenger aircraft
Artist’s Rendering
is now under development. Using “low-boom” technology
developed through NASA research to minimize sound
signatures on the ground, advanced engines, and alternative
fuel concepts, these new supersonic transports (SSTs)
advertise the ability to fly over populated areas with
minimal disruption, cruise more economically, and avoid
some of the potential negative environmental effects of
carbon-based fuels in high-altitude flight.
These new aircraft have attracted interest and some
investment from the U.S. military, and have on occasion
been proposed for military missions by their developers.
Source: Aerion.
The potential roles differ with the size and capabilities of
each aircraft.
Boom Supersonic
History
Denver-based Boom is developing the Overture, a 65- to
88-passenger airliner designed for Mach 2.2 with a range of
Aircraft first went supersonic in 1947. Since then, two
5,100 miles. The company expects to fly a one-third-scale
supersonic transport aircraft (SSTs) served in commercial
demonstrator this year. Projected to enter service in 2029,
airlines. The Soviet Tupolev Tu-144 flew from 1968 to
the Overture is targeted to cost $200 million for the basic
1999, although it was only in commercial service (with
aircraft.
Aeroflot) for three years. The Anglo-French Concorde flew
from 1969 to 2003, most of that time in service with British
Figure 2. Boom Overture
Airways and Air France.
Artist’s Rendering
Due to the technology of their time, those SSTs were
hampered by high operational costs (particularly for fuel)
and operational restrictions resulting from many countries’
prohibitions against sonic booms over land. (A sonic boom
results when the shock wave created by a supersonic
aircraft touches the ground, and is heard as a sharp, loud
report resembling an explosion.) These restrictions
relegated earlier SSTs to trans-oceanic service, excluding
them from a number of potentially profitable routes.
Source: Boom Supersonic.
Current Principal Developers
Boom was founded and is run by Blake Scholl, a former
Three companies are leading the development of new SSTs,
software engineer. It has raised backing primarily from
with a few others newer to the field. The three leaders are at
Silicon Valley venture funds and is partnering with Rolls-
different stages in the process, and targeting somewhat
Royce to develop engine concepts.
different markets. In alphabetical order, they are as follows:
Exosonic
Aerion
Exosonic, of Los Angeles, is designing a 70-passenger,
Aerion, of Melbourne, FL, has completed wind tunnel tests
Mach 1.8 low-boom airliner with a 5,700-mile range. CEO
of its AS2, intended as an 8- to 10-passenger business jet
Norris Tie comes from the aerospace engineering world.
with a 5,400-mile range at a top speed of Mach 1.4. The
The company has yet to announce a timeline for its aircraft,
three-engine jet is anticipated to enter service in 2027 at a
although a subscale demonstrator is reportedly slated for
target price of $120 million. The company was founded by
2025.
entrepreneur Robert Bass and is run by Tom Vice, formerly
head of Northrop Grumman Aeronautics. Boeing holds a
stake in the company, and General Electric is designing the
AS2’s engines.
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Potential Military Roles for Supersonic Transports
Figure 3. Exosonic Airliner
impact of interrupted or degraded communications
Artist’s Rendering
networks.
Special Operations
Deploying small teams to trouble spots quickly for missions
like hostage rescue or embassy defense has been cited as a
role where increased speed can be decisive. (It is less clear
how such a deployment could be kept covert if the teams
are using an aircraft not in common service around the
world.)
Source: Exosonic.
Nuclear Security
Using high-speed aircraft to transport warheads for nuclear
Organizations at earlier stages of development include
weapons to forward units could allow those warheads to be
Virgin Galactic, a private space company, which has
stored in the United States with high security, then sent
teamed with Rolls-Royce to study a 9- to 19-passenger,
forward only when they might be needed—or when
Mach 3 jet;
national commanders wanted to send a signal of possible
consequences to an aggressor and/or reassure allies.
Boston-based Spike Aerospace, which is proposing a
12- to 18-passenger low-boom aircraft aimed at Mach
Intelligence, Surveillance, and Reconnaissance
1.6;
Adaptation of a supersonic platform that flies at very high
Hermeus, of Atlanta, which proposes a Mach 5, or
altitude could give U.S. forces highly responsive, easily
hypersonic, aircraft. Its capacity and schedule are not
redirected intelligence platforms of a sort absent from the
yet announced.
inventory since the retirement of the SR-71.
Possible Military Uses
Humanitarian Relief
The U.S. military already has supersonic fighters and
In a number of scenarios, dispatch of relief supplies,
bombers. Some other military missions could potentially
medical teams, and/or other specialists to areas suffering
benefit from higher-speed travel for people and/or small
from natural disasters, virus outbreaks, or other events
loads of cargo, including but not limited to the following:
could make a positive difference in outcomes.
Executive Transport
Rapid Reinforcement
In September, 2020, the Air Force Research Lab awarded
Moving additional troops to areas under siege or suffering
contracts to Boom (reportedly $2 million) and Exosonic ($1
from surprise attack could enhance commanders’ options
million) to explore the use of their aircraft for executive
and allow the United States to multiply force on short
transport. This followed an earlier $1.5 million contract
notice at times and places of its choosing.
with Hermeus for the same purpose.
Medical Evacuation
The Air Force executive transport fleet currently includes a
Moving wounded personnel to high-level care facilities in
wide range of aircraft used for moving senior commanders,
roughly half the time of current airlifters could significantly
congressional delegations, and government officials,
increase the chances of survival.
including the President. Those aircraft are derivatives of
existing commercial airliners and business jets.
Crew Replacement
Dispatching relief crews for ships or submarines stricken by
Adding speed to personnel transport offers several potential
illness could minimize downtime and restore U.S. sea
benefits. Getting senior diplomats to meetings in times of
presence in vital areas.
crisis could help defuse tensions. Moving senior officials to
remote meetings or site visits in ways that minimize time
A basic configuration could allow a number of these
away from their principal duty station could allow them to
missions to be carried out by the same aircraft. Having to
work more efficiently.
reconfigure the aircraft for specialized missions could
reduce the time advantage a supersonic aircraft would have
Continuity of Operations/Continuity of
over those currently in the fleet.
Government
Rapid relocation of national leaders in time of crisis could
Jeremiah Gertler, Specialist in Military Aviation
enable their presence at command posts and reduce the
IF11778
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Potential Military Roles for Supersonic Transports
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