1. Terrafugia Transition

You can’t really talk about flying cars, or roadable aircraft to be more precise, without mentioning the Terrafugia Transition. It’s been chugging along for a while and it is one of the most developed designs. It had its first flight in 2009 and since then has undergone lots of testing and a few design changes. As the production prototype is flying and making auto show appearances, it looks like deliveries are eminent.

The aircraft features motorized wings, which fold out in roughly 30 seconds for flight, but fold close to the body to allow for storage in a single-car garage or a single driving lane. It is designed to meet LSA specifications, so it isn’t exactly a family hauler, unless there are two or fewer people in your family, but it is spacious enough for two people with luggage.

A pusher prop gets the Transition in the sky and will carry you about 450 miles at 115 mph or, for the mileage conscious driver, you can expect 30MPG on the highway. Since it is equipped with one of the popular Rotax engines, it burns standard unleaded gasoline, which will save you a little money. If you’re interested, you can put a deposit down for your own Transition, which will likely cost just over $275,000 and be delivered late 2012/early 2013. Edit: The longer things have progressed and with the announcement of the TF-2 prototype and lack of deliveries, I think it is safe to say Terrafugia’s Transition is vaporware.

2. PAL-V One

The Terrafugia Transition seems like a capable plane and a decent car, but I’ve got my sights set on something different–the European Pal-V One. In my opinion, it blows the socks off the Transition, I just hope they market it over here. It’s more or less a tandem-seat, three-wheeled car that handles like a sportbike. It looks like a blast to drive, but I’m even more excited about the way it flies. It sports folding rotor blades and, once you slide the tail back, a folding propeller that turn it into a pretty conventional autogyro. According to the company, it will top 112 miles per hour in the air or on the ground.

Since it is basically an autogyro, the Pal-V One is capable of pretty dramatic take-off and landing performance, which is what sold me in the first place. With a lot of designs, you require a runway to get in the air; with the Pal-V One, a decent sized yard is enough to get in the air. It requires only about 500 feet for takeoff and 100 feet for landing.

The PAL-V One has had its maiden flight, which is discussed in this clip, but it doesn’t look like deliveries are expected for some time now.

3. Parajet SkyCar

What would happen if you combined a dune buggy with a parawing? You’d get the Parajet SkyCar. This is an interesting take on the concept of roadable aircraft. It’s a pretty conventional off-road vehicle that only takes about 3 minutes to convert to a similarly conventional powered parachute-type aircraft. Since the wing is soft, it is easy to stow away safely when not in use. Unlike most of the other projects, this requires very little in the way of engineering.

The SkyCar has already made a few flights, including the first flight of a bio-fuel roadable aircraft across the Straights of Gibraltar, courtesy of an expedition from the U.K. to Timbuktu in 2009. Due to the limited aerial range and speed, about 175 miles at 70 mph and 3,000 feet, the SkyCar is best used for aerial surveillance and route planning, as it was on the 2009 excursion.

Despite the limited range, I’m sure there are many applications for such a vehicle, but I’m more concerned about how easy it is to control and take-off and landing lengths. I’ve seen a few clips where it seems like the SkyCar is right on the edge of crashing, furthermore, apparently there was an incident during the expedition in which the SkyCar was damaged on landing. It also looks like it needs a lot of ‘runway’ While this is fine for a toy, something you’d take out to the desert for fun, for any valid applications outside leisure flying in rugged areas, it simply must be easy to control and get off the ground in very little space. Now, I understand that things happen during flight tests, so hopefully they’ve gotten some of the kinks worked out since then.

The SkyCar is available for purchase now. Deliveries are expected in late 2012. A deposit of £10,000 gets you in line for delivery of your £55,320 SkyCar.

4. I-TEC Maverick

Similar in form to the SkyCar, the ITEC Maverick was born out of a need for missionaries in areas with unimproved roads to have a means to hop obstacles that would have previously stopped them for days. Like the SkyCar, it is a parawing attached to a dune buggy like vehicle. Unlike the SkyCar, they elected to go with a control system like that of a car; you press the gas pedal to go and turn the wheel to steer.

There is a great article on the first flight posted on I-TEC’s page, which highlights a little of the intricacies of flying such an aircraft. The main concern seems to be rigging the controls correctly to avoid any kind of turning tendency and making sure the wing doesn’t get tangled up, which is easy thanks to the Maverick’s innovative wing deployment system.

The Maverick’s 190 HP Subaru Engine will get you to 60 MPH in just 3.9 seconds without the wing topping out around 100 MPH. In flight it tops out around 40 MPH. It is street legal and licensed under LSA rules with a gross weight of 1,430 pounds. With 30+ MPG fuel efficiency, the Maverick has a 450 mile range on the ground or a 3 hour flight endurance. It is also compatible with floats in case you need to deploy it from the water. In all that makes for a very capable vehicle and an exciting roadable aircraft.

The Maverick is available now for $94,000. It is available as either an E-LSA or experimental amateur-built kit. A deposit of $12,000 will get the ball rolling on production, with a set of payment milestones to meet as production continues. There is a ton of information on their site and they’ll be at Airventure, so be sure to stop by and see the Maverick in person.

5. Plane Driven PD-X

Plane Driven’s PD-1 is intended to be a plane first and a roadworthy vehicle second. In furtherance of this goal, the Plane Driven team started with a popular kit design and set out to make it roadworthy. For those familiar with the Glasair Sportsman, some of Plane Driven’s most complex modifications are readily apparent–the drive assembly that powers the rear wheels for road use. In order to boost stability, the entire assembly slides back, which required some pretty hefty modification.

In the air, the PD-1 is capable of reaching speeds up to 140 MPH and altitudes up to 15,000. After some design changes, the PD-1 was redubbed the PD-X. As part of the changes, a new 100 HP engine was fitted for the drivetrain allowing the PD-X to reach speeds in excess of 70 MPH on the road. In both cases, I’d say that Plane Driven is on the right track for a very capable and fun roadable aircraft.

As the PD-X is currently in development, there isn’t a lot of information on availability, but the company is working toward producing a kit for sale that will allow you to modify your own Glasair Sportsman with the PD-X. No word yet on cost, but it is still early, yet.

6. Samson Switchblade

The Samson Motorworks Switchblade is perhaps the most ambitious project on this list. I’m not trying to minimize the others, they are truly innovative and exciting, but Samson Motorworks is on an entirely different level. Their Switchblade is currently in the earliest stages of development, but they’re making steady progress. I wish them the best of luck, because I really want to see this thing come to market. The Switchblade will be sold as a kit; you can put a deposit on one now, but deliveries aren’t expected until early 2013 or later. The projected cost to complete a flying and driving Switchblade is about $85,000.

The Switchblade will be an absolute beast reaching speeds in excess of 100 MPH on the street and 190 MPH in flight. Better still, it sips auto gas with a 40 MPG fuel efficiency on the ground and 25 MPG in the air. When they say, “There is nothing ‘mediocre’ about this vehicle,” they are serious. Based on these specs and the following video, this looks like it will be an exciting vehicle.

7. Scaled Composites Model 367 BiPod

The BiPod is the only project on this list that will never be commercially produced (except maybe the Terrafugia Transition). It isn’t intended to ever be anything more than a testbed for other technologies. I don’t like that, but it isn’t my project. I include it here because it represents a pretty novel take on the roadable aircraft genre.

Performance wise, the BiPod is intended to be a high-performance airplane capable of operating from short strips and reaching 200 mph in flight. A 700 mile range is expected. On the highway, the BiPod is meant to hit 70 MPH or so and is designed for urban driving and storage in a conventional garage. At the very least, development of the BiPod should lead to some new technologies that can advance other roadable aircraft beyond what is currently possible in either realm.