The U.S. Army has officially chosen the Sikorsky-Boeing SB-1 Defiant to replace the long-serving CH-47 Chinook helicopter. The selection marks the end of a competitive process that began in 2022, when the service sought a new medium-lift rotorcraft to modernize its fleet. The SB-1 Defiant will be designated as the CH-47F Block II, continuing the Chinook lineage while introducing significant technological upgrades.
The SB-1 Defiant features a coaxial rotor system, which eliminates the need for a tail rotor. This design allows for greater speed and payload capacity compared to traditional tandem-rotor helicopters. The aircraft is powered by two General Electric T700-GE-702D engines, providing enhanced performance in high-altitude and hot-temperature environments. The U.S. Army plans to acquire up to 1,000 SB-1 Defiant helicopters over the next several decades.
The CH-47 Chinook has been a staple of Army aviation since the 1960s, serving in numerous conflicts and humanitarian missions. The new aircraft aims to address limitations in speed, range, and survivability that have become more critical in modern warfare. The SB-1 Defiant is expected to carry a crew of three and up to 33 troops or 15,000 pounds of internal cargo. External sling load capacity will reach 26,000 pounds.
Sikorsky and Boeing will begin delivering the first production SB-1 Defiant helicopters in 2028. The initial batch will undergo rigorous testing and evaluation before full-rate production begins. The companies have established a manufacturing facility in Colorado to support production. The U.S. Army expects the first operational squadron to receive the new helicopters by 2030.
The CH-47 Chinook replacement program is part of a broader effort to modernize the Army's aviation fleet. The service has identified the need for a more capable medium-lift helicopter to operate alongside the V-280 Valor tiltrotor and the Future Long-Range Assault Aircraft. The SB-1 Defiant will complement these platforms by providing a versatile medium-lift option for a wide range of missions.
