When, if ever, do siege towers stop working - and how can we tell?

Question

When, if ever, do siege towers stop working - and how can we tell?

Nothing in Civipedia or that I can find on Google.

Answer 1

I have used this tactic to win before. Despite logic's disapproval, a siege tower stacked in the same tile as a helicopter allows the late, light cavalry unit to ignore walls. With the final light cavalry promotion to extend movement points to support units of the same tile, a group of 5 helicopters with a few siege towers bound to them can destroy a city/turn (if terrain/enemy placement allows). This means that building a number of siege towers before obsoletion could erase the need for artillery class units in mid-late game wars.

Basically- yes siege work, even with helicopters and the least of likely melee class units. I expect it to be patched out in the future, however it does add another strategy to mid-late to late game warfare.

Answer 2

I can't speak from experience, but I have heard Siege Towers continue to be effective even though you can't build them. I remember one comment recommending to save several.

Siege Tower's ability is that a melee unit can attack city health directly, bypassing walls. So this would be fairly easy to test, pop an Infantry in a Siege Tower and see if the majority of the damage is against the city health (bottom, green bar) as opposed to the wall health (top, blue bar).