# Kinetic Energy Weaponry

## Main Question or Discussion Point

A while back, I read a Tom Clancy book in which they theorized about a weapon based on kinetic energy. In short, they would drop huge steel rods that were controlable in order to eliminate buildings and the like. These weapons were protrayed as extremely powerful.

So, on to my questions:

1. Would weapons like these work and be efficient if brought up on board the http://www.nasa.gov/mission_pages/constellation/ares/aresV/index.html" [Broken]?

2. If so, how much energy would be released by the resulting concusion and what are the implications for destructive magnitude?

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Dale
Mentor
Well, the Ares 5 can take a 188,000 kg payload to LEO, which is an altitude of 180 km - 2000 km. So let's say that the entire payload is a single 188 tonne "rod" which is dropped from 1000 km to free-fall to the target and let's further assume that the air doesn't slow it down on re-entry. Then, that 188 tonne rod will have an energy equivalent to 381 tonnes of TNT.

Conventional bunker busters go as high as 44 tonnes of TNT, and tactical nukes go as low as 300 tonnes of TNT. So it would be more like a very small nuke than a very large conventional explosive in terms of energy.

Of course, the assumptions are pretty unrealistic, but a fun "what if" anyway.

Where would I find the formulas to calculate the differing forces at different weights from different heights while taking into account drag?

Dale
Mentor
I don't know, I neglected drag.

And then, just imagine if you rocket-accelerated it towards the ground target!

A thrown rock is a "kinetic energy weapon".

It might sound impressive, but it's neither new nor necessarily the most efficient way to go about things....especially in taking out buildings.

Although they still work well in certain applications. A form of armor piercing round is a "kinetic energy weapon". It utilizes a sabot (which breaks away) to transfer as much energy as possible into a small/ dense projectile made of tungsten carbide or depleted uranium. It punches a hole through armor simply by means of kinetic energy.