The US spends $100 billion to develop helicopters to replace the Black Hawk fleet.

Defense contractors Lockheed Martin and Boeing announced they are developing a high-speed helicopter called the SB-1 Defiant to compete with Bell Helicopter to replace the US military's Black Hawk helicopter fleet.

The Lockheed-Boeing prototype helicopter, scheduled to make its first flight in 2017, features a futuristic coaxial rotor design, with one rotor sitting atop the other. It is one of two helicopters ordered by the US Army to replace the venerable Black Hawk.

The SB-1 Defiant faces a stiff challenge from Bell Helicopter, which is building the V-280 Valor hybrid helicopter. The V-280 is a tiltrotor aircraft that can take off and land like a helicopter, but can rotate its rotors to fly as fast as a fixed-wing aircraft. It is also expected to make its first flight in September 2017.

Model of the US Army's future SB-1 Defiant helicopter

In 2013, the US Army authorized the demonstration of the SB-1 Defiant and V-280 Valor aircraft after deciding to replace its entire helicopter fleet over the next decade.

The challenges of fighting in the hot, sandy, and mountainous terrain of Iraq and Afghanistan exposed the limitations of the Black Hawk and AH-64 Apache helicopters, creating an urgent need to develop attack helicopters that could fly higher, faster, and farther, while carrying more weapons.

The competition between the SB-1 Defiant and the V-280 Valor is part of the U.S. Army's Future Vertical Lift program, an effort to replace the Army's entire helicopter fleet, including the Black Hawk, Apache, Chinook, and Kiowa helicopters.

The program to replace the entire US Army helicopter fleet is expected to cost more than $100 billion.

Despite the development of next-generation combat helicopters, the army has announced that it will not purchase new helicopters after 2030, citing severe cuts in the force's procurement and modernization budget.

According to Anninhthudo