First, let's set something straight: the Transition has many times been referred to as a "flying car" and we too have been guilty of this in the past. To be fair, it is a car that can fly, but the representatives from Terrafugia are quick to point out that this is more a plane you can drive. And, looking at the thing, that's pretty apparent. For natural reasons fewer concessions have been made in the interest of getting through the air than cruising down the highway.
The core concept is of an aircraft that you can fly into a small airport, fold up the wings, and then drive the short distance to your destination. (We're told most people are within 30 minutes of a civilian airport.) This has a number of benefits, not the least of which being the cost of a hangar rental, which can run upwards of $1,000 a month for a light aircraft. This thing you can drive home and park in the garage.
Also imagine a frequent traveling businessman flying into a small airport for a nearby meeting. Small airports don't have rental car terminals and so it'd be difficult to get from that airport to the meeting. With the Transition you can just drive there -- and make quite an impression when you arrive.
The thing is largely made of carbon fiber for lightness and strength, but also relies on aluminum and titanium components. These too are lightweight but, more importantly, they're corrosion-resistant. This is a consideration most aircraft don't need to worry about but the Transition, driven on salty roads, most certainly will.
It isn't a rocketship, though. Cruising speed is 100mph in the air, where it'll net about 20MPG burning inexpensive 91 octane fuel. On the ground, when the flat-four engine powers the rear wheels (not the propeller), drivers can expect about 35MPG. Respectable, but keep in mind it only seats two and has storage space for a few overnight bags. (Yes, your golf clubs will fit behind the passenger seat.)
This small size is in part required by the FAA's Light Sport classification, which means pilots can be certified to fly the thing in about half the time of a typical license. And, while the $279,000 price tag may scare off daydreamers, those looking to buy a small aircraft will know that's actually quite fair, and the extra practicality here could make this downright affordable -- relatively, anyway.
The Transition is up for order now if you're convinced, the first units set to be delivered next year. However, Terrafugia only plans to deliver 10 of these next year and orders already number in the hundreds. In other words, if you're in a hurry to get in the air, this may not be the choice for you.