Sikorsky–Boeing SB>1 Defiant Unveiled, Flight Test in Early 2019

IndraStra Global

Sikorsky–Boeing SB>1 Defiant Unveiled, Flight Test in Early 2019

By IndraStra Global News Team

Image Attribute: Sikorsky–Boeing SB>1 (SB-1) Defiant at Sikorsky’s West Palm Beach factory / Source: Sikorsky-Boeing

Image Attribute: Sikorsky–Boeing SB>1 (SB-1) Defiant at Sikorsky Development Flight Center (West Palm Beach, FL / Source: Sikorsky-Boeing

On December 26, 2018, The first prototype of Sikorsky–Boeing SB>1 (SB-1) Defiant was unveiled to the public via a company press statement. The company also provided a pair of images showing the helicopter (registration number N100FV) from the front and rear, sitting on the tarmac of Sikorsky’s West Palm Beach factory. 

The 30,000 lb (13.6 t) high-speed rigid counter-rotating coaxial compound rotary aircraft is jointly developed by Sikorsky, a Lockheed Martin company and Boeing for United States Army's Joint Multi-Role Technology Demonstrator (JMR-TD) program. The prototype aircraft is powered by two Honeywell T55s engines. But, the SB>1 serial production will have Future Affordable Turbine Engines (FATEs) which is being tested by General Electric at its military engine center in Lynn, Massachusetts, and has demonstrated a 35% reduction in specific fuel consumption (SFC); an 80% improvement in power-to-weight; a 20% improvement in design life; and a 45% reduction in production and maintenance costs relative to currently fielded engines.

The SB>1 was previously scheduled to begin flight testing in 2018 (initially, the flight tests were scheduled for 2017), but after officials detected a technical setback due to undisclosed issues that arose during "propulsion system testbed (PSTB)" runs over the last few weeks, the first flight test got postponed. Now, it is pushed back to early 2019 as it requires 15 hours on the purpose-built PSTB to verify drive, control and engine systems before being certified to fly. After the first flight test,  the SB>1 will slowly get into a gradual, phased flight test program which will be completed within 6 months from the date of the first flight.

Image Attribute: Sikorsky–Boeing SB>1 (SB-1) Defiant at Sikorsky’s West Palm Beach factory / Source: Sikorsky-Boeing

Image Attribute: Sikorsky–Boeing SB>1 (SB-1) Defiant at Sikorsky Development Flight Center (West Palm Beach, FL / Source: Sikorsky-Boeing

The SB>1 Defiant as one of the JMR-TDs, is one of the latest iterations for the U.S Army's Future Vertical Lift (FVL) program under which a family of new utility helicopters expected to enter service in the early 2030s.

The Evolution of SB>1 Defiant's Design


The SB>1 builds on the flight testing of the X2 Technology Demonstrator and the S-97 Raider light tactical helicopter demonstrator. Both development programs were self-funded by Sikorsky and its suppliers. The airframe combines a primary composite structure with metallic components in an engineered structure that minimizes weight.

Image Attribute: The schematic of SB>1 Defiant / Source: Lockheed Martin
'
Image Attribute: The schematic of SB>1 Defiant / Source: Lockheed Martin

According to Sikorsky SB>1 Defiant Chief Engineer Steve Weiner, "The basic features of X2 technology continue to be the same — fly-by-wire, active vibration control, integrated propeller, high lift-to-drag rotor, increased operational envelope, low pilot workload. All those features have been incorporated into Defiant, just like previous X2 designs. To date, the Defiant has all the performance with a lower weight empty fraction than previous X2 designs".

Where most helicopters would have a tail rotor, the SB>1 has a pusher propeller to provide forward thrust. That propeller allows SB>1 to reach turboprop speeds, like a tiltrotor, but, unlike a tiltrotor, SB>1 never stops being a helicopter.



Image Attribute: The Transmission System Test Bed at Sikorsky's West Palm Beach Factory. First Test Run was conducted in 2016 / Source: Sikorsky Graphic. 

The Reference - S-97 Raider


Video Attribute: Sikorsky and Boeing used the S-97' Raiders technology and design process as a basis to develop the SB>1 Defiant. The aircraft itself is a derivative of Sikorsky's X2 technology platform/ Source: Lockheed Martin's Official YouTube Channel