The title says:

"When attacking with a primary weapon from your primary firing arc, you may roll 1 additional attack die. If you do not, you may perform an additional attack from your auxiliary firing arc."

Does it mean I have to attack with a primary weapon in order to trigger the second attack? So I fire shoot ordnance and then attack a second time with the rear arc, right?

Since all ordnance are secondary weapons, no you can't use ordnance and trigger the title to fire using your auxiliary arc.

The title says:

"When attacking with a primary weapon from your primary firing arc, you may roll 1 additional attack die. If you do not, you may perform an additional attack from your auxiliary firing arc."

Does it mean I have to attack with a primary weapon in order to trigger the second attack? So I fire shoot ordnance and then attack a second time with the rear arc, right?

Yes.

NO!!!!!

You wrote it out. "When attack with a primary weapon..." A secondary weapon is unrelated to your primary weapon and will not trigger the title.

Isn't this this at least the third time this question has come up in the last week or two?

I believe so.

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