Units

The challenger II MBT is still in front line service and will be for the forseeable future, however the last one rolled off the production line years ago and as there were no foreign orders the line was shut down.
They could produce more I guess, but at a significant startup cost on rebuilding the production line\reemploying the staff, sourcing parts etc.

I hardly see it as significant enough to warrant a gameplay limitation. The UK is its own Civ in the mod and a modern military power, and they as such shouldn't be limited. That's what we're doing for third-world countries with obsolete tanks purchased from first-world countries when the latter developed modern AFV technology.

For that matter, I noticed that some nations are still producing tanks globally considered obsolete, like the T-72, so we might need three Tank Unit Classes plus more than one researchable technology pertaining to tanks.

I got an idea... lets split all units in tiers and work it in this way... just need help with names and stuff like that... taking an idea about not buildables unit in tha start (representing the need of modernizate armies) as Tier0... and adding near future units (if will be an awkard game if it only lasts 3 years...)
Example:

Inf

tier1: basic infantry/conscripts/guerrila
tier2:normal inf
tier3: special inf/future warrior (see wiki)

tank

Tier0:Stupidly old tanks...
tier1: (old ones) T72/M60
Tier2: abrams/t90/callenger2/merkava4
Tier3:... ok out of ideas here

Jets

tier0: (not buildaibles) F5/mig21/Mirage 3
tier1: F16-18/mig29/Suk27
Tier2: F18-F16/Eurofighter/Mig31
Tier3: Raptor/F35/Su-PAK FA/Shenyang JX

Helicopters

Tier0:no idea
Tier1:Mil24
Tier2:Apache/Mil28(I love them!!!)
Tier3:no idea

and stuff like that... i will also love to see diferent tipes of missiles and/or rockets (weapons like used by the hamas)

NOTE: We already have internationally accepted generational tiers for Jet aircraft. Were currently in 5th generation fighter tech (F22), it will outclass every other fighter in the game period.

Bahmo, for gameplay reasons I can see why letting unit out of production in RL continue to be produced in the game would be a good idea. And yeah, stuff like the t-72 is still rolling out of the factories because they are affordable, simple to maintain and look good parked outside the presidential palace Not everyone can afford a Leopard II

Linky to aircraft: http://forums.civfanatics.com/showpost.php?p=6845065&postcount=2

yea for aircrafts... but not for tanks, infantry or helicopters... also it would be good to add to that naval units

fair point.

So I take it what Eerdna means for Tier 3 tanks is a futuristic type. I don't know exactly how many future technologies we have in the mod, so I don't know whether this is a good idea, but I do support the Tier system. When I started coding I was setting all obsolete tanks to be part of the "Tank" unit class, whether they were used in WWII, Vietnam, or any other era, but that's not a good system when you have to deal with some tanks that are technically obsolete but still built by some nations. So yeah, I'll go back over it to code tiers, and I also need whoever handles technology coding to add some things to that document.