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Personal Air Vehicles: An Idea Whose Time Is at Hand


Whether you¡¯re a professional who takes multiple commuter flights every month or a driver facing daily commutes in stopped traffic, you¡¯ve likely dreamed of having a Personal Air Vehicle (PAV) that would whisk you above the traffic directly from home to your destination.

For decades, engineers have worked on delivering such a cost-effective solution, only to conclude the technology wasn¡¯t ready. But now, advances in multiple disciplines are finally bringing the era of the PAV to reality.

One of the big advances was regulatory, rather than technological. Implemented in 2004, the FAA¡¯s Sport Pilot/Light Sport Aircraft Rule provided a modification in light-plane build standards, and streamlined the process for pilot certification.

These changes, and the resulting potential new market for personal aircraft, caused many innovators and entrepreneurs to jump into the game or to renew efforts they had already begun. This has created a growing market for owner-piloted Personal Air Vehicles.

At the same time, the introduction of Very Light Jets created a growing market for medium-range air taxi services. Very Light Jets carry six to eight people and require only one pilot.

Because they are fuel-efficient and typically cost between $1 million and $2 million, they have attracted affluent owner-pilots as well as entrepreneur-pilots offering jet services at very competitive prices.

To date, demand for VLJs has been stunted by the Great Recession, but we expect a strong comeback in the coming decade.

Despite these regulatory and marketplace changes, people still face significant obstacles when they consider becoming a pilot and owning a plane. These obstacles essentially boil down to six challenges that are rapidly being resolved.

The first challenge is the need for an air traffic control system suited to controlling a swarm of relatively small, slow aircraft flying at low altitude.

Such a control system will be required to efficiently use the airspace around and within urban areas, ensuring that collisions are avoided. Today, low-altitude airspace is ¡°uncontrolled,¡± except in the immediate vicinity of major airports. As PAVs become commonplace, air traffic density will rise dramatically, adding to the level of awareness needed to pilot a plane.

Fortunately, technology already exists to create an automated air traffic control system that monitors the flight path of every aircraft and defines a ¡°highway in the sky¡± for it to safely follow.

The second prerequisite for the PAV mass market will be vehicle designs that are safe in spite of unavoidable mechanical failures. It¡¯s one thing to have a car engine stall while driving on the highway. It¡¯s simple enough to just pull over to the side of the road.

But, when the vehicle you¡¯re driving is flying above the highway, a sudden loss of power can cause a catastrophic situation. Therefore, the design of any mass-market PAV will be required to return it safely to the ground when there is loss of power or a structural failure.

One approach, which has already saved lives in traditional small aircraft, is a ¡°whole-plane parachute.¡±1

Another method is the use of rotor blades that provide safe, unpowered descent. Designs that enable planes to become ¡°roadable¡± ? that is, able to drive on highways ? will possess an additional inherent safety feature. If dangerous weather arises, the plane can land and continue on the road.

A third prerequisite for success will be an expanded network of small airports.2 The current number of regional and small local airports would be too limited for the increased traffic. In addition, most people do not live close enough to an airport to reap the benefits of a PAV.

Some PAV designs would allow vertical takeoff and landing, which means a backyard or driveway could become a ¡°personal airport,¡± but other concepts require a modest-sized runway.

The solution will be multiple micro-airports or verti-ports in urban and suburban areas that accommodate small PAVs, providing easy access to aircraft from homes and offices.

The Comparative Aircraft Flight Efficiency Foundation (CAFE)3 envisions so-called ¡°Suburban Airplane Vehicles¡± that would transport people between these micro-airports.

The vision is to have takeoffs and landings occurring every 30 seconds from the micro-airports that require as little as two acres.

For this vision to become a reality, two technical challenges for planes need to be met: short takeoff and limited noise. NASA has issued a $1.6 million ¡°green challenge¡± to build a plane that can take off in less than 2,000 feet, cruise at 100 mph, and be no louder than 78 decibels at 250 feet.4

The fourth prerequisite for PAVs to tap a large market is the development of computerized flight systems that will enable pilots to operate the vehicles safely even with minimal training.5

The component of flying that keeps the average person out of the sky is not cruising at a set altitude, but the complexity of navigation and take off and landing. This aspect of flying is the reason large planes have multiple pilots.

The answer is to let an on-board computer handle take-off and landing just as it already handles most other aspects of the flight. Such a new flight management system from GE is already available for large aircraft.

It automates navigation and landing to such a degree that it may soon be possible for commercial flights to have just one pilot. A scaled-down version could enable almost any adult to operate a PAV with the same level of training teens receive before getting a drivers license.

Originally developed to operate unmanned military airplanes, this GE system has performed well in trials, navigating flight situations better than a typical human pilot could.

The fifth prerequisite is the availability of materials and engine technologies that will enable fuel-efficient, low-maintenance operation. It¡¯s a simple matter of economics.

Shortening a trip from the suburbs to the city or replacing a commercial flight by flying from one micro-airport to another saves time. However, there is generally no cost savings.

Therefore, for most people, fuel, maintenance, and amortized capital costs will need to be comparable to those of a higher-end car plus the airfares that were avoided.

One of the first ¡°roadable aircraft¡± approved by the FAA has the ability to be driven to the airport at 35 miles per gallon, and then fly at 100 miles per hour to a destination, burning fuel at 20 miles per gallon.6

Brian Seeley, president of CAFE, envisions the day when the small planes used for short intra-city hops will get over 200 mpg and cruise at 120 mph.

The sixth prerequisite required for PAVs to become economically viable will be a set of business models that enable them to be money-makers. As with any industry, economies of scale will bring down prices on the planes. But demand from private owners alone will not build this industry. There will need to be commercial applications of PAVs that will increase demand, but that means they will need to make economic sense.

Some of these business models will undoubtedly include ¡°air limo services¡± that appeal to high-end professionals and fractional ownership programs like those now offered for business jets.

In anticipation of overcoming these hurdles, several PAV development programs are well underway. Given this trend, we offer the following forecasts regarding specific programs:

First, despite its radical concept, the Moller Skycar is unlikely to become a commercial success any time soon.

The Moller Skycar has been in development since the 1960s and suffers from being too ambitious even for today¡¯s technology. Like a Harrier jump-jet or the new F-35 fighter, the Skycar takes off and lands vertically, using vectored thrust. This approach requires enormously powerful engines and very precise control. Largely because of the development of its unique super-high thrust-to-weight engine, Moller has missed many deadlines. For the proposed price of around $500,000, this 350 mile-per-hour four-seater could make a huge dent in both the light helicopter and very light jet segments, if only it was available. But after decades of work, the prototype can still only take off and hover over the parking lot. Today, it is at risk of being left behind by less ambitious designs that will be flying while it sits in the test hanger.

Second, the Terrafugia Transition flying car will live up to its name, but will lack the price-performance needed for a big PAV success.

This flying car is a two-seater that flies at a little over 100 miles per hour and takes off from a conventional airport with a 2,500-foot runway.7 The only thing it offers over a conventional very small airplane is the ability to be driven on a road, with a level of performance that is equivalent to a Smart Car. With these limited performance parameters and a hefty price tag of $279,000, it¡¯s doubtful it will generate much interest when it becomes available in 2013. As of this writing, the company has orders for over 100 vehicles.

Third, the gyrocopter-style flying car offered by the Dutch company PAL-V will appeal to a limited market, but it won¡¯t become a mainstream market success.

The PAL-V will offer more excitement than the Terrafugia, since it will take off in just over 100 feet and perform more like a sports car on the road.8 But like the Terrafugia, it is only a two-seater and will fly at an unimpressive 112 miles per hour, which is too slow for practical cross-country flying. It¡¯s likely to be priced between $250,000 and $300,000. So if most of your flying will be local, for less money you could buy a better-performing gyro-copter plus a compact car for less total investment. The flying prototype is now being refined and the company targets 2014 for first deliveries.

Fourth, of all the current PAV designs, the Carter Copter will be the only one to realize true mass-market potential.9

This concept uses a patented technology that merges the best features of helicopters, gyro-copters, and airplanes. It can quickly get off the ground vertically, just as a helicopter does. Then, powered by a pusher-propeller, it accelerates just like a conventional gyro-copter until it approaches a speed of 100 miles per hour. At that point, its so-called ¡°Slowed Rotor/Compound technology¡± shifts the load from the rotor to its airplane-like wings. This enables the Carter Copter PAV to travel at 255 miles per hour, which is faster than any commercial helicopter or gyro-copter. Finally, like a helicopter, it can land vertically in areas that are inaccessible to fixed-wing airplanes. This entire transition process is handled by on-board computers that make it as easy to fly as a low-end gyro-copter. The much slower designs from Terrafugia and PAL-V cannot take off and land vertically. Like the Moller Skycar, the Carter Copter PAV carries four passengers and can land and take off vertically in a backyard. But, unlike the Moller, it uses a conventional off-the-shelf aviation engine and it slowly settles to the ground under pilot control in the event of engine failure. The Carter Copter is also highly scalable; in addition to developing the four-seat PAV, Carter is working with Textron and the Department of Defense to create two military designs. One version could be called a ¡°flying Humvee¡± and the other is the size of a C-130 and can fly at speeds of up to 400 miles per hour. For reference, the world¡¯s speed record for a conventional helicopter is 249.1 miles per hour. A prototype of the Carter PAV is currently flying and living up to all the claims made for the technology. The initial four-seat version is expected to be offered at a slightly higher price than that of the two-seat Terrafugia, perhaps around $300,000.

References List :
1. MSNBC.com, December 24, 2004, "Parachute System Can Save Small Planes." ¨Ï Copyright 2004 by msnbc.com. All rights reserved. http://www.msnbc.msn.com 2. GizMag, December 19, 2010, "Pocket Airports Would Link Neighborhoods by Air," by Ben Coxworth. ¨Ï Copyright 2010 by GizMag. All rights reserved. http://www.gizmag.com 3. For comprehensive information about the CAFE Foundation, visit their website at: http://cafefoundation.org 4. Popular Science, January 5, 2010, "Automated Air Traffic Control System Enables Fewer Pilots, Flying Cars," by Stuart Fox. ¨Ï Copyright 2010 by Popular Science. All rights reserved. http://www.popsci.com 5. GizMag, December 19, 2010, "Pocket Airports Would Link Neighborhoods by Air," by Ben Coxworth. ¨Ï Copyright 2010 by GizMag. All rights reserved. http://www.gizmag.com 6. Bloomberg BusinessWeek, April 3, 2012, "A Flying Car for Just $279,000," by Brett Berk. ¨Ï Copyright 2012 by Bloomberg L.P. All rights reserved. http://www.businessweek.com 7. Associated Foreign Press, April 2, 2012, "U.S. Flying Car Cleared for Takeoff," by Andrew Beatty. ¨Ï Copyright 2012 by the Associated Foreign Press. All rights reserved. http://www.google.com 8. Los Angeles Times, April 4, 2012, "Flying Car PAL-V Is Tested," by Deborah Netburn. ¨Ï Copyright 2012 by Los Angeles Times. All rights reserved. http://articles.latimes.com 9. For information about the Carter Copter, visit the Carter Aviation Technologies website at: http://www.cartercopters.com/