Four ways the DEFIANT X military helicopter defies convention

The fastest, most maneuverable, most survivable military helicopter in history is on the horizon

April 15, 2021 in Innovation, Technology

By Rachelle Lockhart and Ed Muir, Boeing writers

Thirty aircraft, carrying 360 soldiers, lift into the air and disappear into the night. They fly low and fast, grouped in six formations.

The mission is to secure a sensitive infrastructure complex deep in enemy territory. To get to the landing zone, they will have to fly twice the length of New Jersey, through a web of enemy air defense.

Once at the landing zone, soldiers will travel on foot.

The helicopters weave through tree lines, a valley, then over a riverbed — too low to show up on radar and too fast for adversaries to even get a shot off.

The last mile of flight is the most dangerous. The landing zone is surrounded by hostile forces. Pilots must maneuver the aircraft on the spot to land quickly and smoothly — and then get out the second soldiers disembark.

DEFIANT: The highly maneuverable DEFIANT X delivers unmatched survivability in high-threat air defense environments and flies twice as far and twice as fast as the Black Hawk helicopter it is designed to replace.


Speed, reach and maneuverability are critical to mission success and to ensure everyone comes home.

Someday, this imagined scenario could be DEFIANT X in action.

DEFIANT X is an advanced utility helicopter and air assault weapon system that can fly low and fast, land quickly, deliver soldiers to the objective area (known as the “X”) and get out — all while evading the enemy in complex terrain. It will revolutionize the Army’s air assault capability and be the fastest, most maneuverable and most survivable military helicopter in history. 

Recently, Sikorsky and Boeing released details about the new aircraft, which is the team’s entry for the U.S. Army’s Future Long Range Assault Aircraft competition, a top modernization priority for the service. 

The Army is expected to issue a request for proposals later this year, with contract award anticipated in 2022.

MISSION CRITICAL: Five DEFIANT X aircraft fly in formation at high speed, through contested territory, to deliver mission-critical equipment to the landing zone.


Nate Morgan is one of the Boeing engineers working on the DEFIANT X program. His team is involved with system integration, analysis and safety.

“Our role is to ensure all the parts and systems of the aircraft work together, safely and efficiently,” he said.

Morgan has worked on vertical lift programs since 2013, but he is especially excited about DEFIANT X because it is a clean-sheet aircraft that incorporates state-of-the-art technology and innovation. According to Morgan, four aspects of DEFIANT X make it exceptional.

Coaxial Rotor System

Two sets of composite rotors are stacked atop each other. The rotors’ rigidity, along with the pusher prop on the rear of the helicopter, enables DEFIANT X’s game-changing speed, exceptional maneuverability, and enhanced acceleration and deceleration. DEFIANT X will fly at speeds exceeding 230 knots, twice as fast as the Black Hawk helicopter it is designed to replace.

“It’s an air assault weapon system with all the advantages of a traditional helicopter and the speed, range and payload of an airplane,” said Morgan.

ADVANCED: DEFIANT X boasts an advanced coaxial rotor system, pusher prop with clutch, composite fuselage, retractable landing gear, fly-by-wire controls and a cabin for 12 troops — while fitting in the same footprint as the Black Hawk helicopter.


Fly-By-Wire Flight Controls

Advanced flight control software and pilot interfaces coupled with redundant control surfaces reduce the workload for aircrew and provide the framework for autonomous operation.

Composite Fuselage

Advanced materials and manufacturing techniques reduce weight, vibration effects and corrosion in harsh environments.

Model-Based Engineering

The tools and processes used to develop DEFIANT X are fully model based. Model-based engineering (MBE) uses a digital system model integrated during all stages of the development in order to form a robust digital thread of program data, which increases first-time quality and safety. This approach also enables early discovery of issues during development; facilitates rapid technology insertion later in the program; and forms the basis of digital twins, which can be used to support the aircraft once fielded.

“This is industry-leading use of MBE, not just in the military helicopter realm,” Morgan said. “We are evolving and innovating processes along the way, and it is an amazing opportunity for the team.

“It’s a special time in the industry to be able to develop a helicopter from paper to proof,” he added. “This only happens once in a generation.”

Learn more about DEFIANT X

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