Problem with that design, is every time it banks, one side where passengers will be sitting will become weightless, while the other side of the plane will be subjected to G force. So only in level flight does every one across the plane have even gravity like a normal plane. They are still working on a way around that last I herd.What? That just looks like a longer 737 with four small engines instead of two big ones.
What you want is this: http://www.nasa.gov/centers/langley/ima ... -81-01.jpg
That's different.
This fact has yet to stop any 4 engine plane, let alone a twin engine plane. On September 11th when all flight got ground a watched a C-5B land with #1 & #2 motors flamed out, only had the right side, and it made a perfect landing like all were still working, they just landed long since only the reverser's on the one side worked. As long as they have a rudder you should be fine...unless you fly the B-2A, in witch case there are so many other flight surfaces that the Flight Control Computer(FCC) will just take care of every thing any way, just like any other modern plane with FCC'sHaving the engines half way out along the wings make it fairly inefficient if one fails. Having them close to the centreline of the aeroplane, such as a DC-9, VC10, BAC 1-11 & 727, means it has a lot less of an effect should you lose an engine. In a 4 jet in the configuration of the A340, 747 and 707 type, lose two on one side, and compared to say the VC10/IL62, life could be very interesting, and lead to a very aching leg!
If they figure out a way to make inertia dampeners, and a way to properly pressurize odd shapes, that will be when we get to see really cool designs be implemented.