Front / side armor on Lightning

Side armor is universally better of the 2 IMO,esp if u manage to hull down behind a low ridge or in a terrain dip - you will usually have your side armor towards the enemy so you can duck in cover,and while the only think they can see is the turret facing them,if they hit it it will count as a shot to the side.
It is also significantly better when engaging vulcan harassers since it is impossible to always keep your front facing them even with rival 3,and from the side you have the largest hitbox = more shots taken.

Your calculations show resistances vs enemy MBTs, but you should know if you wish to engage enemy heavy tanks in a slugfest armor is not the way to go.In such cases the only viable option is stealth, so you can reach an advantageous position with your gun facing their *** and your frontal armor facing them before the engagement even begins,and you get the 1st shot on top of that.

Aside from everything else that has already been written in the thread, the 3 slots to use when you are pulling a lightning without a very specific plan in mind are either stealth/NAR for obvious reasons or mine guard since even at 1st rank it allows you to survive a double mine cluster.

Side armor is very very situational, but at least in general it will perform better then front armor.
Front armor is only good when using AP vs other lightnings in CQC, or when sniping at long ranges, and in the 2nd situation the advantage you get is minuscule.
Neither one will give you any chance to win 1v1s vs an AP MBT.

Eh no, I was a lil' tired when I wrote that. You CAN have FS and Armour, but not stealth on top of that. My bad, but my initial point remains. You do not have to choose between FS and Armour - you can have both. Stealth however takes the FS slot (IIRC - one of them anyways). Still looking at the tests ppl have done here you can basically add the maxed out FS repair on TOP of that for the lightning.

I survive by avoiding to get hit. I can do this by driving at high speeds behind cover or in circles at range, rather than standing still in a slugmatch. This means I get side-hits... if I get hit at all. Front armor is only useful for slugmatches.

But I have enjoyed the AP lightning experience immensely with a stealth frame. Great for sneaking up on them or avoiding enemies if I'm fast enough. Also allows me to avoid aircraft more easily, as they can't use the auto radar spot. Especially when I'm driving behind enemy lines, aircraft don't look at my faction colors a lot and low-flying aircraft will happily pass me by, and tanks can sometimes miss you as well.
I also use it for my Skyguard, makes it easier to play hide-and-seek when there's Liberators around or angry pilots you killed and are looking for you in a tank.

Well - let me say up front that I am NOT a primary tanker (so no doubt there are others more qualified to answer than me) but my impression is the best armor is largely decided by your approach to combat.

If you are in a engaged in a farily large zerg-style siege-battle at a distance then front-armor makes the most sense since you can front-load (literally) all your protection to the direction where you are going be taking the most fire from. The thing about this for lightnings is that a lightning is usually suboptimal for this role to begin with. A main battle tank is usually more suited. An AP lightnings damage output is very good, but for front-line combat it is inferior in most other respects to the MBT.

Side-armor tends to be better for most other situations where you can't expect to know where you will get shot from - and it's the shots you don't see coming that are going to get you killed... that also synergizes more with a lightnings role for either flanking - dealing with infantry, or skyguarding, since in all those situations you don't heave a clear and narrow "front" towards the enemy. Also it certainly helps the side-armors case that you have 2 sides (your largest sides to boot) protected by it versus the front-armors 1 side, so on average given a chaotic situation side-armor gives you a lot more protection all things considered.

TLDR; I'd consider side-armor generally more useful for lightnings, but it really depends on what you are doing with it. If you specifically want to hunt MBTs with it you probbly have to leverage front-armor + flanking to stand a real chance.

-Stigma

Look...listen i understand what you say, and what you want to achive. Playning like you describe, then use SideArmor. Play like in the movies, racing around and "dodging" shots at high speed and trying to "outmanouver" the slower, bulkier enemy.
It sounds fun and MAKES SENSE if you think about it for 5 seconds. Hundreds and hundreds of lightning drivers play like that in this game.

Only...

It is still wrong.

You should actually NOT play like that. It gets you nowhere and is just a mindtrap for beginners.
For vehicle-combat, only ever use Front Armor. Adjust your playstyle, plain and simple. Only take hits in the front. Practice THIS, not dodging.

In the lightning, getting even 1 hit in side (Even EXPOSING the side) only means one thing:
A colosal mistake has happend. You need to evade NOW. (evade="total unconditional retreat" not "dodge around")

Sidearmor is only for AI, plain and simple. For rushing a crowd with VIper etc.

Dont be that "speedy, dodging" noob in vehicle combat. Be better than that.

... what?
Speedy and dodging is much, much more useful than full-frontal tanking. Just look at the first post, by dodging one shot you are already better off using side-armor than front armor. Using front armor means you use the "stand still and pound" method, at which point you should ask yourself why you aren't using the AP MBT with front armor.

It's not a newby method, in fact, all I see is that people stand still and pound rather than use it's speed and mobility to it's advantage. I doubt you know how to use it properly. I've attacked 2 AP Prowlers with it and killed one, then got away while dealing good damage against the second with this method. In direct slugfests using the armor you simply cannot compete against other MBT's, and if you can you were usually better off using an AP MBT rather than lightning.

Just the fact that you think that the front armor makes so much difference shows you are more subjective about it. The statistics shown by the OP are clear: only against an AP Vanguard is the side-armor weaker, if you didn't buy it. Ofcourse, against other vehicles this might matter more, but even then... The scores are so close that dodging one shot already brings you on par or better than front armor slugfests.

Stealth goes in the defense slot. The only things in the utility slot are Fire Suppression & IR smoke.

I'm with you. I find Side armour much more useful, esp in conjunction with Rival. I'm constantly trying to flank the enemy while in a Lighnting, rather than hitting them head-on. If I find a safe position on their flanks with good cover/concealment, I'll stay stationary if they don't see me. Once I'm detected though I try to keep on the move.

Most tankers can't hit moving targets for ****, so I keep moving along lateral vectors to my targets, doing strafing runs, circling, hitting their flanks, dodging in, out, and around cover, etc. Side armour + Rival works wonderfully for peek-and-shoot tactics from cover as well. Even out in the open, it's amazing how many tankers can't hit you if you simply show them your broadside at a distance and rock backwards and forwards.

And if I do end up getting hit, I can usually retreat to nearby cover for repairs before they land the 5-7 shots it takes to knock me out.

This type of combat does raise the Lightning's skill floor considerably since it's harder to move-and-shoot than it is to just face your target, hull down, and slug it out while stationary with an enemy who is doing the same. But I find I last a lot longer while remaining mobile like this and have way more fun as well. And for mobile warfare I find Side armour better than Front.