Half-scale model. Video of first flight comes after renders. More info from Wired's Danger Room here

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Comment by Gary Mortimer on July 25, 2009 at 12:08am
I'm seeing amazing forward speeds being claimed for this once its developed further, 420kts, can't see it myself.This one is funky enough for Wired ;-)

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Comment by Gary Mortimer on July 25, 2009 at 12:12am

Comment by IKE on July 25, 2009 at 1:38am
IMHO this is a very compromised design. The most obvious problem is the lack of space but this maybe at least manageable. However I think that there are two fields that this is conceptually very compromised.

Firstly the company says that with the electric retractable fans in the wings the main engine can be optimized for cruising in airplane mode. However at least at the prototype stage the main jet engine provides about 70% of the total vertical thrust, so either it is over sized for cruise (with the respective weight and consumption penalties) or the aircraft can barely take off vertically.

The other problem which I think is the most serious one is the transition phase. After the plane take off vertically (just, because as the company said it cannot hover) it has to recline the jet engine, to retract the fans inside the wings and also to roll 180 degrees!. There is a very elaborate maneuver there and the total combined energy of the aircraft (aerodynamic lift from the wings, thrust from the jet engine, thrust from the fans) seems inadequate.

It seems a very complicated concept (maybe unnecessarily).

Another article from Graham Warwick .
Comment by Jack Crossfire on July 25, 2009 at 3:21am
It could use more rate damping. Definitely a wobbly ride. When do they start underslung payloads?
Comment by Robert Drone on July 25, 2009 at 6:38am
Will they be able to find a battery to power the large fans for the full scale model? Seems like that would require a really good power source?
Comment by Adam Kaplan on July 25, 2009 at 4:24pm
I haven't looked too far into the Excalibur's numbers, but does the promised 420 knots top speed (air or ground, anyhow?) account for payload? I read somewhere that it can pack four Hellfires.

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