US Army pledges to launch new class of high-speed rotorocraft

SOURCE:Flight International

US Army aviation branch leaders have pledged for the first time to break from upgrading the service's conventional helicopter fleet and field an all-new rotorcraft with a minimum top speed of 200kts by 2030.

Maj Gen Anthony Crutchfield, aviation branch chief, committed the service to the new rotorcraft in a speech to the Army Aviation Association of America on 17 April. He also set a list of requirements for the vertical lift machines that will replace the Boeing AH-64 Apache andCH-47 Chinook and Sikorsky UH-60 Black Hawk in 19 years.

The army's "next-generation aircraft" must be at least 30kt faster than the top speed a conventional helicopter can achieve due to the limitation of retreating blade stall, which caps forward velocity at roughly 170kt, Crutchfield says.

It must also be optionally-manned, fly 848km (526mi) missions, remain on station for 2h, hover at 6,000ft with temperatures above 35ºC (95ºF) and carry a 9-person crew plus weapons and sensors, he says.

"I don't think we can do all those things just by incrementally improving our current aircraft," Crutchfield says. "It's going to have to be something new."

Since cancelling the RAH-66 Comanche in 2004, army aviation leaders poured billions of dollars into upgrading existing helicopters with new propulsion and avionics systems.

That investment has produced a healthy inventory of aircraft that are in high demand in the wars in Iraq and Afghanistan, but army aviation branch officials believe the service will need faster and more survivable aircraft after 2030 to remain effective.

"I don't want my grandchildren flying the [AH-64 Apache] Longbow Block 80," Crutchfield says. "[The Apache] a great aircraft but we need technology to take us further into that future."

Crutchfield's vision aligns the army with recent investments by Sikorsky in the coaxial-rotor X2 high-speed demonstrator and by Piasecki with the compound-rotor X-49A Speed Hawk.Boeing, meanwhile, has started early development of a high-speed vertical lift concept called the Disc Rotor. Bell Helicopter has revealed a concept for a "hybrid tandem rotor", and also has fielded the high-speed V-22 tiltrotor with Boeing as a partner.

In Janaury, the army issued a request for proposals for concepts to develop a replacement for the UH-60 and AH-64 with a single aircraft called the Joint Multi-Role (JMR)-Medium. The JMR also is envisioned to be scaled up to replace the heavylift Chinook or scaled down to replace the Bell Helicopter OH-58 Kiowa Warrior.

But army officials have not finalized plans for launching the JMR-Medium programme, or even whether the Black Hawk/Apache replacement should come first.