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  • Northrop Grumman Flips Out
    Posted by Bill Sweetman 3:13 PM on Mar 26, 2009

    The Northrop Grumman bomber design unveiled last week was certainly a bit odder-looking than we expected, but that was only half of it. Same people, one week later, and a new patent:

    blog post photo

    What the... heck?

    We can safely say that the canard is going to play merry hell with the radar cross-section, and with that aspect ratio is not going to do much for the aerodynamics either at a Mach number of more than 0.5. It's therefore a very good bet that the missing feature is the arrangement of pivots and cover panels that allow the canard to swing back into the leading edge and disappear when it's not needed.

    Score one for the patent attorneys, who have managed to protect the swing-canard flying wing without showing it, by patenting the two shapes separately.

    Why do it? Because an all-wing design can often fly at a greater weight than that at which it can take off. The B-2, for example, can refuel in flight to 367,000 pounds, about 15 tons more than its normal take-off weight. The main reason is that there's no tail to rotate the airplane to an angle of attack where it can take off at such a weight:  the only rotation power is from the elevons, which don't have much leverage and hence have to supply a lot more downforce. Off the ground, at higher speeds, the angle of attack doesn't have to be as sharp and the trim forces are acceptable.

    A big canard at the tip of the nose lifts upwards and has a longer moment arm than the trailing-edge surfaces. On the NGB, it would probably even let you use those surfaces as flaps. Overall, therefore, you would end up with a smaller and lighter airplane for a given payload of fuel and weapons.

    Compared with the non-canard design seen last week, you'd expect this version to have a bigger take-off weight and to have correspondingly more power;  but the empty weight would not be vastly greater and payload and range would be better. If you wanted (for example) to carry the Massive Ordnance Penetrator, this might be a way to do it. The canard would also be good for a stealthy tactical airlifter - but the timing of the patent suggests that there's a closer-term focus here.

    And doesn't that high-aspect-ratio canard seem familiar?

    blog post photo
    Wikimedia Commons

    Rutan also developed a variable-sweep (not retractable) canard for the Beech Starship, but enough of that monstrosity. And as we all know, Rutan's Scaled Composites was acquired by Northrop Grumman in July 2007. Since which time, as noted here, it has not visibly done much for the new owners. Keyword is "visibly".

    Tags: ar99, ngb

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