Flight International 09Mar2020

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UNMANNED SYSTEMS

Special report

36 | Flight International | 3-9 March 2020

Five key technologies to make attritable aircraft practical and cost effective

ADVANCED MANUFACTURING

Digital engineering will be key to balancing the

cost and capability of attritable aircraft, before

building prototypes and flight testing, says

Shane Arnott, director of Boeing Australia’s

Airpower Teaming System programme.

“For example, through application of digital

engineering, Boeing Australia has a digital twin

of the entire Boeing Airpower Teaming System

aircraft design that we’ve been able to ‘fly’

thousands of times under different scenarios to

test aircraft performance, the mission system

and many other components necessary for

capable attritable aircraft,” he says.

Tools such as additive manufacturing,

autonomy in the fabrication plant and digital

engineering, are needed to quicken the pace

of innovation, says Scott Wierzbanowski,

programme manager for the US Defense

Advanced Research Projects Agency’s Dynetics

X-61A Gremlins programme.

“Whereas it may typically take three to five

years to build a clean sheet autonomous air

vehicle, driving the build cycle down to 12 to 18

months not only regulates non-recurring costs,

but also pushes cutting edge technology out to

the field sooner,” he says.

TRUSTWORTHY AUTONOMY

New forms of flight control automation and

artificially intelligent software need to be

developed to manage the burden on over-

worked pilots and ground operators.

“Scaling up quantities of deployed vehicles

must be done in parallel with the reduction of

the number of human operators required to

control them,” says Tim Keeter, Dynetics’ X-61A

Gremlins programme manager. “From force

composition, to mission planning, to engage-

ment, the commander’s intent needs to be

clearly and simply communicated by the

operator and autonomously implemented by

artificially intelligent agents distributed through-

out the system.”

Autonomy is also needed to cope when

adversaries, such as Russia or China, use electronic

warfare to jam or disrupt communication between

operators and unmanned air vehicles (UAVs).

“Denied environments will stress these future

systems to intelligently adapt when individual

aircraft are lost, to identify new threats or chang-

es in an adversary’s tactics, and to quickly fuse

data from multiple, distributed sensors for con-

sumption by the swarm, as well as by the hu-

man operator,” says Keeter.

SIMPLER JET TURBINES

Because attritable aircraft would likely only have

lifecycles of 20 to 30 missions – more than sin-

gle-use cruise missiles, but less than manned jet

fighters – new turbines need to be developed

to fit this novel application.

“The cost of engines in the 700lb [3.1kN]-

thrust and smaller class is a significant factor in

the cost of an attritable vehicle. Lower vehicle

costs promote greater use of attritable vehicles,

which increases the demand for engine produc-

tion,” says Keeter. “Additionally, engines opti-

mised for reuse with quick refurbishment times,

as opposed to being expendable, offer a great-

er advantage for attritable vehicles that are also

recoverable. A revisualisation of engine design

to reduce parts count, materials, machining and

touch labour costs that are achievable through

additive manufacturing and new production

technologies is key.”

CHEAPER MISSION SYSTEMS

For an attritable aircraft to be low-cost enough

to be lost to combat attrition, its subsystems

and payloads also need to be inexpensive.

“There are certainly payloads that can fit the

attritable price range, but many are at the lower

end of the capability spectrum or are

single-mode and -capability systems,” says

Steve Fendley, president of Kratos Defense &

Security Solutions’ unmanned systems division.

“There will likely be continued focus on

producing mission payloads near the technical

edge of the envelope, but with an objective for

a significantly reduced cost, where even the

high- capability payloads can be considered

attritable.”

Another approach would be to network in-

formation gathered from inexpensive sensors

across a group of UAVs, giving operators data

without having to risk a single $5 million to $10

million multi-mode sensor, he says. “UAVs

would be deployed in numbers and would work

as teams to satisfy the mission requirement.”

AIRBORNE RECOVERY

More work needs to be done to perfect recov-

ering UAVs in mid-air, says Keeter.

“While most may struggle to think of air-

borne recoverability as a technology, it is in fact

a collection of enabling technologies like

precision navigation, recovery systems, robust

safety systems, aerial networks, mass property

management, structural design elements and

specialised avionics,” he says. “Attritable

aircraft that are recoverable allow vehicle costs

to amortise across multiple uses, enables use of

high-performance and high-cost payloads, and

lowers average mission cost.” ■

ANALYSIS GARRETT REIM LOS ANGELES

Air teaming requires new forms of control

automation to reduce the burden on

pilots and ground operators

Boeing

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