Well I have a feeling that PDS systems do NOT work against fighters, but there's NOTHING in the text on PDSs that says so. It just says that unmodified rolls of 1/3/5 fail against shields.

My thoughts on this:

[*] Fighters (and ships) cannot attack from a range of 0.
[*] Fighters are therefor at a distance ot at least 1 when they shoot.
[*] This means that fighters are far enough away that their fire should be able to be intercepted by a PDS system.
[*] Fighters, however, do half shields.
[*] Being at a range of 1 means that when they shoot, fighters are far enough away that their fire should be able to be fully intercepted by a shield.

Thus, my final conclusion is this:

[*] The fact that fighters are at a range of 1 is an abstraction that the game makes in order to avoid firing arc questions for ships that are in the same hex.
[*] Fighters have the ability to half shields due to the fact that they are actually much closer than range 1 and are, in fact, under the shields much of the time.
[*] Since fighters are under the shields, they are also within the minimum range threshold for a PDS to be able to target and track the incoming fire.

In summary: Fighters ignore PDS systems.

But that is just my thought on the subject.

Same here...

And if somehow there's a new rule change that says that fighters ignore shields I have to say I don't like it. I think that fighters halving shields but only scoring a hit on a 5-6 is a well balanced system. But that's me!

According to the strict reading of the PDS rules, and thus given the absence of any mention of fighters,  the rule-lawyer in me says that officially (AFAIK) fighter fire IS intercepted by PDS, BUT the common-sense wargammer in me feels that perhaps it shouldn't.   

I never really used PDS systems in the past, and I was writing stats for a new fleet and decided to use the buggers. For instance I have a size 6 CL with shields-3 and PDS. So if normal fighters attack it, they would normally score PEN hits on a 3+ (3/2 = 1.5, RU = 2) BUT because of the PDS only PEN rolls of 4 and 6 would get through. Given that you have to pay extra in terms of cost and space for PDS that seemed fair.

If you add to the mix AFBs though, that little ship becomes particularly fighter-resilient   :twisted: ... interesting...

Another thing I also noticed with PDSs (I'm sure, again, that this has been discussed before) is when you fit one on a shield-5 ship, you get no benefit vs PEN rolls, but when what I call the "flood driver" gets in (ie when you finally get that shield hit, dropping shields to 4) you still get that protection from the PDS (ie ignoring '5's). It almost acts like a surefire Redundant Shielding system.

Whew!
While I don't know if I agree with your conclusion, at least I no longer am confused.