Ions only ever do 1 damage. Is this always face down?

Ex: player A rolls "hit", "crit", "crit" against a TIE fighter with an ion cannon. TIe fighter rolls "blank", "blank", "blank".

Do you just ignore the dice and deal 1 damage? Or do cancel normal hits first, then crits until there is one remaining?

The dice rolls are used to establish whether you hit or not. Evades cancel [boom] and [kaboom] results in the normal manner.

if there are any uncancelled [boom] or [kaboom] results then the attacker has "hit" the defender.

If the attacker hits, you now ignore the dice results and apply one damage and one Ion token to the ship. If the ship has shields, you lose a shield, if it doesn't have any shields, you deal one facedown damage card.

Thank you sir. That's all I needed to know.

Just to clarifying,

if I attack with missiles, get 2 hits and my opponent rolls 2 evades, then I didn't actually get a hit?

Does that then mean that munitions failsafe kicks in a I don't discard the missle weapon card?

A lot of cards use "a hit" to trigger other things. So I must get at least one more hit than he gets evades to actually activate the trigger event?

OR

An ion cannon needs a hit to do extra stuff. It attacks and gets 2 hits, defender gets 3 evades. Does target get a damage and/or an ion token??!

Just to clarifying,

if I attack with missiles, get 2 hits and my opponent rolls 2 evades, then I didn't actually get a hit?

Correct, that's a miss.

Does that then mean that munitions failsafe kicks in a I don't discard the missle weapon card?

Correct again.

A lot of cards use "a hit" to trigger other things. So I must get at least one more hit than he gets evades to actually activate the trigger event?

Yes, correct again. In order to hit, your [boom] or [kaboom] results must outnumber the evades.

OR

An ion cannon needs a hit to do extra stuff. It attacks and gets 2 hits, defender gets 3 evades. Does target get a damage and/or an ion token??!

See my first post up the page (#2). In this instance, the opponent has sucessfully evaded and the Ion Cannon does nothing else.

The definition of "hit" is on page 12 of the rulebook: "If there is at least one uncanceled or result remaining, the defender is considered hit (see page 13)."

The die result is called "hit" as well. That's misleading. The rulebook does not use that name. I think.

The rulebook does not use that name. I think.

That is correct, though the "how to play" video FFG produced does use the name and I think Frank has called them "hit" results in emails at some point. It is confusing to call the results "hit" though, which is why I love the [boom] and [kaboom] name the community has come up with.