This idea is practically prehistoric. Players have been doing it since they had drawbridges with which to launch dwarves!
A big rule for Bay12 is to never assume that we have yet to weaponize something, after day 1 since it's implementation. You will always be let down. Always.
But, yes. Drawbridges provide two functions that can be weaponized easily and cheaply: Tossing enemies around, and smashing them into non-existence. The latter is known as an atom-smasher, and is a very efficient method of eliminating peoplegarbage. You can't really get them to safely or reliably deploy troops, though, so it's hardly worth it to try that.
It's even on the wiki:
http://dwarffortresswiki.org/index.php/Stupid_dwarf_trick#Bridge-a-pult
yep, thank you for fast reply, but i think i've been misunderstood a lil (maybe because of my poor english?). The question is not to cause harm with bridge but to try to move creatures with it rather harmlessly.
Trying to figure my questions in a more strainghtforward way:
1. Is it possible to control a firing range of a dwarfpult? If if build a 10-tiles long bridge and 2-tile long, will the first one launch objects for a greater distance?
2. If we have stones, the first is lying on the 1st tile of the 10-tiles long bridge and the secong is on the 10th, will the distance travelled be different for them?
3. What is about safe landing? Creatures like keas being shot with bolt usually break bones, get some bruises and become stunned when falling from 3-4 Zlevels. Will dwarves perform better if they are wearing some armor? And what about shields, do they help?
4. The next thing I want to ask about is poultry and other small animals (like cats). Some of them are said to get a little to no falling damage. We can modify raws to be able to train war chickens and launch them to the goblin sieges without loosing much of them upon impact.
5. And the final one: falling objects are said to harm creatures they fall on, aren't they? What if flying, enclosed into steel shell, dwarf will slam into gobbos copperhelmed head? Will it be counted as a STRIKE?
I believe there is a lot of !science! being made in that direction, can someone post a link or describe it briefly?