if your talk about catapults
I have a 379 page book about catapults
to fire 1lb you need a ballista that is 4w and 6l feet long
10 lb is 8w and 13l feet long
60lb is 16w and 24l feet long
180lb is 22lb and 34l feet long
if viking than i show that they do not runway of figths they did figths but lost only because of the wall
http://www.viking.no/e/england/index.html viking settlements in england
also thier three seige of Constantinople
I found the one I was talk about was in 907 AD
" Oleg effected a landing on the shore and had some 2,000 monoxylae equipped with wheels. After his boats were thus transformed into vehicles, he led them to the walls of Tsargrad and fixed his shield to the gates of the Imperial capital.The threat to Constantinople was relieved by peace negotiations which bore fruit in the Russo-Byzantine Treaty of 907. Pursuant to the treaty, the Byzantines paid a tribute of twelve grivnas for each Rus' boat." thier are no Greek sources of this, but in the Kievan Rus it mention that the the first Rus'–Byzantine Treaty was concluded in 907 as a result of Oleg's raid against Constantinople