Don't use them much either. But they are the only air units that can occupy a town after destroying all the city defensive units. So if you like battleships...you might want to move a helicopter along the same sea squares. They have good reconnaisance (spot subs) and comparable movement. So Battleships and helicopters are a powerful duo.

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They call me Mr. Fierce

I don't think they are so great. they don't do to much and they cost alot.

List of units i've never builded before:

1. AEGIS Cruiser (yeah...good fleet escorts,but no need for them against AI)
2. Archers (find some in the huts,but never buid a single one)
3. Artillery (got some from Leo)
4. Cannon (see #3)
5. Fanatics (never been in fundy against AI)
6. Helicopter (i like stealth bombers better)
7. Legion (see #2)
8. Marines (i like battleships better)
9. Paratroopers (i don't use nukes)
10.Partisans (got some when losing a city)

Archers, chariots, destroyers, crusiers, caravels, helios, partizans, marines... rare builds for me.

I built a helo once. I built subs in one game. Actually, I can't remember ever building a carrier! It's easier to capture an enemy airbase or small city with paras, since they have a range of 10 which usually reaches across the seas on civ maps.

I never/rarely build:

1. Horsemen (usually have a few from huts)
2. Elephants (not agressive that early)
3. Catapults (same reason)
4. Caravels (wait for frigates)
5. Cannon (prefer Dragoons)
6. Arty (prefer Cavalry)
7. Fanatics (Fundy vs AI too easy)
8. Marines (prefer paras for beachhead & assault from land)
9. Subs (slow; don't fit my naval strategy)
10. Helos
11. Carriers
12. Nukes

What many of U seem to NOT build... guess what? That's exactly what i do build!?

Let me preface by saying: i'v graduated to strictly playing with other humans. Tho i do occasionally play with myself (if no one is watching).

So what follows is based on MP, deity level, usually 1x, restless or raging, random of preferably med or large(i love to explore new worlds).

ARCHERS: 2nd unit i want... after horses. They defend as well as anything up muskets. Have enuf counterattack, especially if vets(which is what i build), to kill anything up to muskets. Almost as important; they are the only military unit that takes 30 to build so it's quite easy bang them out or rush build them at the sign of barbs or other aggressors (they make easy "change", so-to-speak).
Plus, combined with a couple of horses, make a great barb-leader-killing team (& in deity=150 gold, i LOVE that!).

EXPLORERS: as don Don says... they make GREAT scouts! Ignore ZOC's & U can approach suspected enemy positions from ANY direction. Move 2 & back off 1, move 2 backoff 1 = in anything but all clear terrain; there's not a unit that can touch'm.
AND even tho they can ignore others' ZOC's... others can't ignore theirs = great for freezing that elephant/dragoon/cav unit so it can't wipe out your main attacker force! He-he.
AND THEN of course, there's always their favorite pastime... hut-hunting in every last unexplored region; like the polar caps(they can even run from hut-hordes if U do the approach rite).

CARVELS: often, but not always. Like'm because they carry 3 vs frigate's 2.
PLUS i just LOVE blowing away those pesky little triemes that bug U sometimes & even an occasional horse or settler on the shore if carvel is a vet.
Actually, i LOVE frigates, but at that stage of the game other tech's usually take priority... unless i'm an island nation. Then it's navy all the way & Megellan's=cruical. Then your little carvels speed along their little shuttle routes for the rest of the game.

FANATICS: NEVER used to build pre-MP, because playing solo, NEVER went into Fundy govt. Believe me, if U havn't played into the modern era against some good, SMART, UNPREDICTABLE human leaders... then U have a lesson to learn about the value of Fundy & those dirt-cheap, 4-defense/2 hit-point, get-in-the-way, blitzkrieg-slowing, little fanatics.
You havn't experienced the FULL range of this fantasticaly diverse game until your democracy takes on a Fundy that knows what he's doing!!
For the cost of 1 helio or armor, U can build 5 of these little rascals. Put them in fortresses & slow down anything short of a nuke attack!!
U hate'm or ya lov'm... depending on which side of the war your on.

HELIO's: what Smash asked about before all this started. True very expensive(don't U wish they could carry troops@that price?!); really too bad they are so costly. But...
If you can afford to produce a few of them (& don't bother building as vet's); they make excellent sea patrols (just like real life).
Few things can kill them at sea, they can stay "on station" for many turns, they spot 2 squares, & they can sink little piss-ant naval units like subs, transports, & destroyers when they try to sneak into your space!
ALSO, as mentioned above, they make a good combined arms attack by stopping partisan formation & occupying an emptied city(whereupon they become instantly refreshed).

Whew! Sorry, must be the caffine in my fingers. Other than that... have a good day!

PS: Sten S/S'Fart/others that play their way... we GOTTA play. Our styles are so diff, it would be most interesting.
So ICQ me some time, big boy.

Explorers are must have units. Just to explore the land before attack.

1. Find and destroy subs and transports.
2. Find and kill settlers, engineers, caravans, freight, diplomats and spies -- especially in remote areas.
3. Exterminate unwalled cities (always attack from over land squares to do this) which could later be used as airbases or ports.
4. Prevent establishment of new cities.
5. Eliminate huts I have no hope of getting to.
6. Harass distant, isolated cities in order to divert resources away from the area I really intend to attack.
7. Find and destoy explorers and scouts.

Helicopters are very useful in games in which opposition cities are not yet walled --which frequently happens in those games where the opposing civs develop late. But they are certainly not useful in all games.

First, you get Helos with CA, so think of them as combined gunships and troop transports. That's why Helos can occupy a city. There wouldn't be enough troops to constitute a whole Rifles unit, and they're only effective when used with air cavalry tactics.