The tactics that are used play against the weapons we face. There are three types:
Type 1 - small arms/shoulder weapons (7.62mm/.30 cal and including RPG's) - these are ineffective against helos which are operated above 800 to 1000 ft and flown at speeds above 60 to 80 knots. Employ diving fire with rockets and circling engagements with turret. Avoid low speed, low altitude. Vietnam tactics
Type 2 - Crew served automatic weapons 50 cal/12.7 and above - engage at long range, using standoff weapons. Avoid overfly at any altitude below 4000 feet, at any speed. Can be engaged from low NOE altitudes if the gun position is known and split fire engagement from simultaneous attackers can be arranged. Very difficult to engage if multiple sites having overlapping effective range and with radio link are found.
Type 3 - Shoulder fired IR missiles - Stand off and stay low. Easy to engage when site is known, very hard to know! Use background clutter and NOE tactics, which are very effective, especially if aircraft has IR supression. Avoid use of type 1 tactics, as they put you squarely within the missile's kill zone.
Iraq is confusing, as they have all 3 types in abundance, all soaked into a passive civilian populace. This is not military work, it is police work, and not for the faint of heart. Those who use diving fire techniques will avoid the small arms and die from the missiles and crew served weapons.