Future Shock

Eurocopter X3

Those of you, who think the modern helicopter looks about as cool and thrilling as a Reliant Regal, think again because some developments that seemed too advanced to be convincing in the 50s now look as if they can redefine rotorcraft.

Vertol VZ-2

The words are as futuristic as the concepts: Fenestron, tiltrotor, tiltwing, proprotor... Most of them come from far back in history like the concepts they designate. Today's technology, however, makes them a lot more reliable and efficient. Finally, the ideas of over half a century ago have a chance of becoming valid alternatives to traditional designs. As for the difference, just compare modern developments to, let’s say, the Vertol VZ-2.

Fairey Rotodyne

I love the Fairey Rotodyne. There was only one flying prototype, and that was scrapped in the 60s – still a mystery as to why. For me, the dream lives on. It was a compound helicopter using a tip-jet-powered main rotor driven by two turboprop engines that also provided forward thrust through propellers after takeoff. Driving the main rotor by air from compressors, as opposed to a shaft, helped it avoid torque. The Rotodyne completed 455 test flights without a single accident and achieved speeds of over 165 knots (307 km/h). Imagine my surprise when I come across the Eurocopter X3. It’s a different philosophy, but the looks are so similar. This one’s a modified EC155 with its two turboshaft engines powering the main rotor and the two props. Torque is countered by varying pitch of the propeller blades. It’s fast (220 knots – 410 km/h) and relatively cheap due to simplicity of conversion.

V-22

Unlike tiltrotors and tiltwings, that are exceptionally complex. Just think of the time and costs of the Bell-Boeing V-22 Osprey program, started in the 80s and completed some 30 years and 27 billion dollars later. But it flies, and does it quite well now that the initial design flaws seem to have been tweaked. In airplane mode it reaches 305 knots (565 km/h), and it has already been to war. The aircraft is equipped with complex avionics and a triplex fly-by-wire system for redundancy, and it requires the pilot to be capable of flying both for fixed-wing aircraft and rotorcraft. AgustaWestland is pushing forward with its civil sibling, the BA609. The most compelling ability of this machine is to land in congested city centres, right on the rooftops of buildings where meetings are to take

BA609

place, while cruising at 275 knots (509 km/h) to connect city pairs. Although the BA609 is successful in that it does everything a tiltrotor should, some estimates say that its price will be as high as $20 million, and at a maximum of nine passengers and a range of 750 nm (1390 km) you wouldn’t call that a bargain, whatever the capabilities.

Sikorsky X2

The Sikorsky X2 is as fresh an idea as can be, born in the early 70s, when the company was flying its S69 coaxial aircraft. The X2 takes its achievements a step further using the engineering experience of the last forty years. It has achieved its design goal of 250 knots (463 km/h) on 15 September 2010 and looks a likely base for a new rotorcraft type.

Fenestron on the EC-135

Perfectionists look at the helicopter tail in dismay. The tail rotor is noisy and can be dangerous. Eurocopter’s Fenestron and NOTAR by MD Helicopters are the two viable alternatives. They look cool and improve flight safety. The Fenestron is essentially a ducted fan within a redesigned tail. It’s only practical on helicopters up to five tons due to size limitations. As for NOTAR, this is a different technology altogether, having nothing to do with rotors. A fan inside the base of the tail boom drives pressurised air toward the aft end, and part of it exits through

NOTAR on MD Explorer

slots on the side of the boom. The occurring wave affects the downwash from the main rotor, causing the air to go around the boom and to the side, thus combating torque. A rotating drum at the end of the tailboom is used for control. Such a solution makes the helicopter a lot quieter and safer, while the resulting exterior look is very unusual and hi-tech.

And another exciting thing: Bell and Boeing are developing the Quad Tilt Rotor, a large four-rotor derivative of the V-22. It will be the size of a C-130 Hercules and fly at 250 knots (460 km/h) with a payload of around nine tons. It doesn’t have ducted fans instead of rotors, nor does it have guns, but otherwise it’s just a step away from that huge flying thing in Avatar.