I've been following this guys thread, he did excellent ultra light construction using an external bypass ducted fan to make a full fuse, vertical takeoff A-4B. I've done a rocket and electric profile version in a similar size, but his effort is really special. If you read through the last few pages you can see the contruction of this latest version. He's now working on some in-flow vanes to help prevent the roll on liftoff due to torque since the tail surfaces dont' have sufficient authority till it's moving. I've seen people do the external bypass method on space shuttle ducted fan models and it's really hard to see in the air, this is no different. Really nice.

http://www.rcgroups.com/forums/showthread.php?t=2583502


https://www.youtube.com/watch?v=CCP8CtcoWRg

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