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well ill try this is a huge subject and if u click back a few pages on the forum you find hundreds of aircraft threads
in short:

interceptors INT : group these up in packs of four and wait for bombers to come , then pounce! (air superiority) dont commit too soon and dont go in half strength use as many as your general can command in one spot.

fighters FTR : same as above except go in enemy airspace to make a hole for your bombers.

stukas CAS : use these guys to pound the armies your engaged with fly after battle has been joined (1 hour) use interdict when combat starts (hits org)
and switch to ground attack when they retreat (hits str if low org)

4 engine bombers STR: use these against your enemies cities (strat bombard)
to attack IC and resources they will be intercepted so group them up and use escort brigades or air supriority missions (if u can reach)

mediums TAC: kinda of a mix between CAS and STR can do either or.

NAV: use naval strike to clear out the sea lanes (this is overpowerd)

a note for tac and str: besides the traditional uses, they can be used for "all those other missions"
to support your FTR use them to attack enemy airfields(dmg'd airfields reorg enemy aircraft slower).
to support a heavy siege or brake solid lines use logistical strike (when interdict is not working)
instalation strike is tricky and usually costly it can take out enemy radar or AA (the AA has been nerfed so heavily now u can ignore it usually....)
also any damage u do will be repaired by enemy (as fast as he can) so its for "right now" operations.

lastly port attack uses NAV and STR to attack ships in berth and the port facilities respectively this can be useful if a port is unreachable by you and has alot of damaged ships ( a dmg'd port repairs slower kinda like a damaged airbase)

keep in mind this is by no means comprehensive and you should still leaf thru the posts to glean useful tidbits.
 
regarding naval strikes whether on the seas or at port; CAS are very effective at naval strikes as well. In fact I use them in conjunction with my NAV bombers instead of TACs, keeping the latter planes on continental missions.

If you're playing as a naval power (Japan, Britain, USA) don't neglect the use of planes either in sinking ships or in disturbing convoys. CAS are very effective for both and they're the cheapest option as well.
 
If you're playing DD or ARMA:
Use TAC while attacking a province with a high amount of units on it to help your troops. If it has a small amount and they're not dug in then you may use them to keep their ORG down(interdiction).
If you got CAS use them on moving troops (attacking, fleeing or simply moving does not matter much, tho more effective vs fleeing ones). If you got no CAS use TAC.
INT are good to keep enemy bombes away and for air superiority, although im my experience fighters are superior for air superiority.
Also a word of advice, if you got "old" models of tac don't use them on troops that aren't being attacked, or worse dug-in ones, they may not only fail but also lose lots of str.
STR are good if you want to tear your enemy's IC down, but they are rather useless and a waste of IC if used against big targets such as germany france SOV or the USA. They do miracles vs GB thought. They can also be used to destroy an enemy's infra but tac do that job quite well so no need for str for that sole pourpose.
TRA are good to get some key provinces you can't otherwise get to, using para troops ofc (again awesome vs brittain).
NAV will tear most fleets appart but be carefull not to send them w/o an escort because they are very fragile. If you got no NAV, use TAC since they perform well and only slightly worse than nav in most situations.
Hope that helped you :).