I had never much played with this unit until the last couple of days. I've been missing out. Heads up to anyone else that doesn't mess with them much, they are FUN. I promote them with double movement for a total of 8, and you can pretty much respond to any situation on a continent within a turn or two.
Some strangeness though:
- Helicopters on railroads go really fast. Obviously this is because the metal in the tracks radiates negative propulsion ions at the helicopter in order to accelerate it. I guess this isn't so strange.
- Helicopters can't fly over water, not even Coast. They prefer to swim.
But oh well. These are a new staple of my army. They're a blast! (pun intended)
Another oddity is their penalty for attacking across rivers.
In Zephtyr's immodest proposal are a couple of good suggestions for helicopters.
They are only useful for hit and run. Left in the open they normally don't last more than a turn. But I agree, I always give them double movement upgrades.