Northrup Grumman has built to original German blueprints, a non-flying Horton 229 flying wing in thier El Segundo Plant here in California to test it's stealthiness. Results: it would have been stealth enough that they would have detected it 19 minutes later than conventional aircraft; they would have had only eight minutes warning at regular altitude, and just 2 minutes when flying in at wave height.
http://www.foxnews.com/story/0,2933,529548,00.html
For those not familiar with it; a history of the Horton 229 is here:
http://en.wikipedia.org/wiki/Ho_229
http://www.militaryfactory.com/aircraft ... aft_id=105
A National Geographic program about the study airs on July 5th.
