Norse Giant can't use his three yards long sword

[demonsbane]

I have a small problem with GURPS Vikings 2nd edition -actually, for issues as this I have the same problem with GURPS as whole trying to handle Fantasy.

The Giants presented there have ST 40-50 (third edition score). The Damage entry says: "As weapon". The description of the creature specifies they use inmense versions of human weapons, and for instance the sword of the giant is 15 feet long.

Well, I can to figure the damage from the Strenght (40-50), but where can I to find these inmense versions of human weapons mentioned in my book -for instance that 15 feet long sword?

Due the objective lack of data about these weapons (I can be wrong here, but I'm definitely unable to find them! 4e Fantasy and Banestorm, both have nothing to add here), the entry "Damage: as weapon" (G: Vikings 2nd edition, page 87) remains useless to me.

For figuring out this lacking data, is guessed we have to take standard Broadsword (+1 swing, cutting) and taking this damage number (+1 swing) to the size of that giant version?

Some broadswords are 3 feet long, so this giant sized weapon (15 feet) would cause five times that standard damage, that is to say, +5 swing cutting? Is this the solution? I think not.

If the answer is I need another future GURPS book (4e Low Tech?) for fixing the weapons of the giant... What would mean then actually "Generic" and the "Anything you want" claim from the back cover of Basic Set Characters? Hm.

I had problems as this while handling GURPS third edition, and I still have them in the fourth.

I would love to know what do you think about this issue.