Sikorsky-Boeing Defiant X

History of the Sikorsky-Boeing Defiant X

In January 2021, the Sikorsky-Boeing joint venture team submitted its contender to the US Army's "Future Long Range Attack Aircraft" request (FLRAA), known- "Rebel X". The Defiant X compound helicopter builds on the proven framework of the existing SB-1 "Defiant" technology demonstrator, which is detailed elsewhere on this website.

In testing, the demonstrator exceeded 232 knots (266.98 mph) in dive and 211 knots (242.8 mph) in level flighta remarkable feat for a rotorcraft. The FLRAA race is currently (2021) fueled by bids from Bell (via the tiltrotor V-280 "Valor") and Sikorsky, and is looking for a capable successor to replace the legendary and ubiquitous Sikorsky UH-60 "Black Hawk" multi-mission helicopter.

Both the U.S. Army and the USMC service are actively involved.

Defiant X is marketed with superior performance for its "composite" rotor assembly, which features 2 quad-blade main rotors above the fuselage and a multi-blade "pushrod" strut aircraft draft at the rear of the fuselage . All in all, this helicopter is capable of speeds more common than fixed-wing aircraft while maintaining the hovering capabilities and low-altitude maneuverability/agility of a conventional helicopter. The new aircraft is said to have twice the range of existing UH-60 types, while still being able to perform all of the Black Hawk's current battlefield roles and more.

These include general transport, maritime patrol, troop deployment/evacuation, search and rescue (SAR), reconnaissance, fire support and medical evacuation.

The two main rotors are defined as coaxial, a typical design element of many Soviet and modern Russian helicopters, originating from Mil in Moscow. On the Defiant X, the blades are composite and stiff to provide the required hover and maneuverability.

The main rotor rotates in the opposite direction, eliminating the need for a traditional tail rotor unit to compensate for torque effects, allowing the tail to freely mount a "push" propeller solution, giving the helicopter unparalleled maneuverability and improved straight-line speed over other rotors in this category type. In the Defiant X arrangement, the propulsion propellers are also used to rapidly decelerate the helicopter when leaving the high-speed envelope.

The hull is said to have a lightweight but strong composite structure for field use and general survivability. The helicopter has been engineered to reduce vibration and corrosion when operating in more forgiving environments such as water.

Large rectangular sliding doors are mounted on both sides of the hull, forward amidships.

Specification

Base

Year of Service

2030

Origins

United States

Status

Under development

Program is running.

Crew

2

Production

0

Manufacturer

Sikorsky-Boeing Joint Venture - USA

Carrier

US (probably)

Roles

Transportation

General transport function for moving supplies/cargo or people (including casualties and VIPs) out of range.

Intelligence Surveillance Reconnaissance (ISR), reconnaissance

Monitor ground targets/target areas to assess surrounding threat levels, enemy strength, or enemy movement.

X-Plane (development, prototype, tech demo)

Aircraft designed for prototyping, technology demonstration, or research/data collection.

Notable Features

Radar Capability

Houses may house (via specialized variants) radars for searching, tracking, and attacking enemy elements.

Countermeasures

Onboard electronic or physical countermeasures taken by the aircraft or pilot/crew to enhance survivability.

Armor

Armor assigned to protect the pilot/crew compartment and/or critical operating systems enhances survivability.

Multi-engine

Include two or more engines to improve survivability and/or performance.

Coaxial main rotor

The twin main rotors are assembled coaxially, negating the traditional torque neutralizing tail rotor unit.

Rifle positions

Defensive weapon location for attack/suppression.

Closed crew room

There are partially or fully enclosed crew work areas.

Scalable

Has retractable/retractable landing gear to maintain aerodynamic efficiency.

Dimensions and Weight

Length

36. 1 ft

(11.00m)

Cured weight

8,940 lbs

(4,055 kg)

MTOW

11,023 lbs

(5,000 kg)

Wgt Difference

+?2,083

(+945kg)

Performance

Installed:

Two 7,500 hp Honeywell HTS7500 turboshaft engines, each driving two four-blade main rotors coaxially arranged on the fuselage and a six-blade tail rotor in a "thrust" configuration.

Maximum speed

295 km/h

(475 km/h | 256 knots)

Maximum

9,843 feet

(3,000 m | 2 mi)

Area

280 km

(450 km | 833 nautical miles)

Range (MPH) Subsonic: <614mph | Transonic: 614-921 | Supersonic: 921-3836 | Hypersonic: 3836-7673 | Hypersonic: 7673-19180 | Reentry: > 19030

Armament

Recommended support for 7. 62 mm/12. 7 mm machine guns and miniguns for general fire support/suppression. Up to 8 Hellfire (or similar) Anti-Tank Missiles (ATGMs) can be mounted on optional external stub wings on either side of the fuselage.