In mid-2008, Sikorsky unveiled a revolutionary technology demonstrator. They called it the X2. Just two years later, the very same aircraft was performing unbelievable maneuvers and had unofficially dethroned the Westland Lynx to become the world’s fastest rotorcraft.
The secret behind the X2’s speed and agility was the presence of a set of composite, four bladed, coaxial rotors. Though this area demanded a high level of expertise, Sikorsky had been working on this specific area for decades on different rotorcraft, starting with the X-69 followed by the UH-60 Black Hawk and the RAH-66 Comanche.
What the coaxial rotors meant was that a separate tail rotor was not required. This freed up some real estate on the tail for the addition of the pusher propeller. The pusher propeller produced a considerable amount of thrust and played a major role in increasing the top speed of the rotorcraft. A single LHTEC T800 LHT 801 turbo shaft engine powered both the coaxial rotor blades as well as the six bladed pusher propeller.
Sikorsky unveiled two S-97 prototypes at its facility in West Palm Beach, Florida on October 2nd. “Sikorsky will begin ground testing shortly and is on track for first flight this year,” Sikorsky’s Advanced Military Program Director Steve Engerbretson said. “The entire flight program will take about a year to complete.”
There is good reason for Sikorsky to finish flight-testing of the S-97 as soon as possible. The Stratford based company and its partners have privately funded the entire S-97 program. Therefore, they intend on offering the S-97 to the US Army as a replacement for the OH-58 Kiowa Warrior, a helicopter that dates back to the Vietnam War era, as part of the Armed Aerial Scout program (AAS). The OH-58 Kiowa Warrior was primarily an observation or “scout” helicopter, also capable of fulfilling the light attack role. Due to its small size and ability to get in and out of sticky situations without so much as breaking a sweat, Special Forces operators preferred it. The S-97 Raider seems to be ideally suited for this role, as it not only lives up to, but also improves upon the characteristics of the OH-58 Kiowa Warrior.
With a top speed of almost 220 knots, heavy armament, high power to weight ratio and the ability to carry up to 6 personnel, the advantages of the S-97 are as clear as day. However, if the last couple of years have taught us anything, it is not to be over reliant on technology.
“If it’s not broken, don’t fix it”. It will be interesting to see if the S-97 Raider will be able to achieve what the V-22 and the F-35 as of yet, have not.
|Sikorsky S-97 Raider|
|Role||Scout and attack helicopter|
|National origin||United States|
|Primary users||Unites States Army|
|Length||35 ft (11 m)|
|Gross weight||11,000 lb (4,990 kg)|
|Max takeoff weight||1 × General Electric YT706 , 2,600 shp (1,900 kW)|
|Powerplant||1 (2 coaxial)× 34 ft (10 m)|
|Main rotor diameter||1 (2 coaxial)× 34 ft (10 m)|
|Propellers||6-bladed pusher propeller, Variable pitch, clutchable, 7 ft (2.1 m) diameter|
|Cruising speed||253 mph; 407 km/h (220 kn) (with external weapons)|
|Range||354 mi; 308 nmi (570 km)|
|Service ceiling||10,000 ft (3,048 m) 95?|
|Guns||50 cal gun w/500 rounds|
|Rockets||7 shot rockets pod|