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To: McGruff

“That doesn’t sound very easy.”

Imagine yourself in two-dimensions in a small boat trying to intentionally collide with a large ship.

If you have a navigational chart of the ship channel and know the shipping schedule you could position yourself in the middle of the channel using newly available GPS guidance.

You would have the best chance of achieving a collision if you selected a passage in the channel where the large ship would be following a constant bearing as it approaches your intended collision point.

You could sit there at the most likely collision point facing your craft towards the oncoming ship and you would only have to make very small adjustments to the port or starboard (left or right) to insure a collision, assuming you were not detected on the bridge of the approaching craft.

As a boy my Navy dad taught me “beware the constant bearing” meaning that if your craft is following a constant heading at constant speed and another craft is heading across your bow at a constant heading and constant speed, but the “bearing” (compass position) of the other craft is remaining constant (constant degrees to the left or right of your bow) then you are heading for a collision.

Sitting in your small craft facing an oncoming ship it would be easy to determine whether you should maneuver to the left or right to guarantee a collision, assuming the large ship doesn’t change course. All you have to do is observe whether it is coming straight at you and adjust accordingly.

Now imagine a remotely piloted multi-copter drone remote pilot attempting to achieve a collsion with an airliner where the airliner, like the Alitalia jet approaching JFK, is flying a constant bearing(315 degrees, per Jeppesen) and constant altitude (1,900 feet per Jeppesen) for a mile as it approaches a known optimal collision point (labeled ZULAB on the Jeppesen map and GPS identifiable in three dimensions) right before the airliner begins final descent.

Point ZULAB on the Jeppesen map is a known constant three-dimensional location through which all jetliners must pass on approach to runway 31R at JFK right over Long Beach, NY where the rogue drone multi-copter was spotted “hovering” only 200 feet away from the Alitalia Jet.

A remote terrorist drone pilot positioning the attach drone multi-copter at point ZULAB and facing the drone at bearing 135 degrees (opposite of landing bearing 315 degrees) the terrorist now has a two dimensional target to collide with. The terrorist would only have to position the drone up or down, or left or right to maintain the “constant heading” of the incoming jetliner relative to the drone.

In particular the terrorist would want to target one of the jet turbines of the airliner.


8 posted on 05/02/2013 9:31:43 AM PDT by Seizethecarp ((Defend aircraft from "runway kill zone" mini-drone helicopter swarm attacks: www.runwaykillzone.com)
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To: Seizethecarp

CBDR

Constant Bearing Decreasing Range


30 posted on 05/02/2013 11:25:16 AM PDT by wxgesr (I want to be the first person to surf on another planet (Uranus)
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To: Seizethecarp

You’re confusing bearing with heading. Just because you know his heading doesn’t mean anything with regard to his bearing to you, which is his compass position relative to you. You can be on a reciprocal heading to him, but if your flight path is displaced 50 meters from his, then you won’t collide.

So this will not work without some way of determing bearing of the approaching aircraft. Radar would do it, but I don’t know of any sets that small. A video camera with built-in compass would do it, but I’ve never seen such a thing.

I’m not sure it’s so easy. Yet . . .


69 posted on 05/24/2013 5:53:11 AM PDT by JoeyBlowey
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