Faster than a $20 Hooker and Twice as Much Fun?

The X2 is an experimental helicopter being developed by Sikorsky, an American company, at a test-flight centre in Florida. It recently flew at more than 430kph (267mph), according to a report in Spectrum, published by the Institute of Electrical and Electronics Engineers. _Economist

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Sikorsky's X2 experimental prototype is being developed in order to bring speed to the commercial helicopter industry. The X2 has already flown faster than the official speed record for helicopters, but not officially.

To make an official attempt on the record, Sikorsky will need to have the flight monitored by the Fédération Aéronautique Internationale, which compiles airspeed records. But that is unlikely to happen until the X2 is going even faster. Later this year, Sikorsky hopes it will be zipping along at more than 460kph. The company, however, is interested in more than just breaking speed records. It plans to use the technology developed for the X2 in commercial helicopters.

...it uses two counter-rotating rotors that spin around the same axis, one positioned above the other. So in forward flight each rotor can produce an equal amount of lift on each side, thus providing balance. The idea has been around for some time, but it proved difficult to make it work properly.

What has changed are technological advances in aircraft engineering and control systems. Now, vibrations can be reduced using “active control”, which involves placing sensors around the helicopter to detect the onset of vibration and then using force generators on various parts of the frame to vibrate in such a way that they cancel out the original tremors. Advanced computer modelling has also made it possible to design more efficient rotors. A pusher propeller has been fitted at the rear of the X2 to provide extra oomph. According to the engineers, this propeller can also be used to slow the helicopter snappily. And computerised “fly-by-wire” controls allow the X2 to be flown relatively easily.

Sikorsky reckons that future helicopters built using the X2 technology would be extremely versatile machines. They would dash to and from a medical emergency a lot faster. They would also be very agile in flight, which would increase their capabilities in combat. Sikorsky has already produced a simulator so that potential customers can experience what these fast helicopters will be like to fly. Plenty of whirlybird pilots will be keen to get their hands on the real thing. _Economist

The Sikorsky X2 is competing against the Eurocopter for bragging rights:

The X3 has so far only flown once, in a 35-minute flight that tested its hovering behaviour and Billig says it performed as designed. It won't be going for any high speed attempts until late 2011, but they are initially aiming to bust 400 km/h.

Sikorsky is already well on the way to achieving its speed aim of over 500 km/h. In a test flight in September, the X2 unofficially broke the previous record of 400 km/h, which was set by the Westland Lynx in 1986. The X2 achieved 463 km/h, but due to its propellers, it is unclear if the craft will be recognised in the same category by the FAI, the world's air sports federation based in Lausanne, Switzerland, that oversees aviation records. _BrianWang

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Vertical takeoff and landing (VTOL) aircraft provide crucial functionality for both military and civilian applications. The race for more speed and maneuverability is likely to continue for some time.

And then there is the race to build a flying car for military use.

DangerRoom

DARPA aims to power its flying humvee with a diesel engine, giving it extra range.

According to a company statement, Pratt & Whitney Rocketdyne are going to model the Transformer engine on their EnduroCORE, a diesel engine that generates a “high power-to-weight ratio comparable to gas turbines.” It’ll need to. Darpa’s specifications for the flying Humvee require the Transformer to stay in the air carrying up to 1000 pounds for up to 250 miles without refueling. Diesel’s energy efficiency apparently satisfied Darpa’s suggestion that the Transformer be at least somewhat green. _DangerRoom

Combining land travel with VTOL capability in the same vehicle makes sense for military and expedition-type enterprises. Land travel uses much less fuel, and allows you to take advantage of land-based fuel caches which may not be accessible directly by air. Being able to hop over rivers, canyons, and other obstacles expedites progress toward an objective.

The advantage of a craft that combines the ability to fly, to travel over the surface of water, and to travel over all terrain land surfaces should also be obvious to any would-be Galtist or survivalist.

H/T Bruce Hall