Forum adverts like this one are shown to any user who is not logged in. Join us by filling out a tiny 3 field form and you will get your own, free, dakka user account which gives a good range of benefits to you: No adverts like this in the forums anymore. Times and dates in your local timezone. Full tracking of what you have read so you can skip to your first unread post, easily see what has changed since you last logged in, and easily see what is new at a glance. Email notifications for threads you want to watch closely. Being a part of the oldest wargaming community on the net. If you are already a member then feel free to login now.

From the GW site:

The Sky Ray is a variant of the more common Hammerhead gunship, and provides a dedicated missile platform that is used by the Fire caste to provide point attack fire support for Fire Warrior teams, who lack their own heavy weaponry. When guided by the markerlights of Pathfinder teams, the Sky Ray makes an exceptional perimeter and air defence missile system.

Question: How many missiles can the Skyray fire at all, and how many per turn?

The codex provides an answer in the armoury entry of the missiles, but not in the entry of the Skyray.

The skyray can fire two missiles per turn using it's networked markerlights. Additionally, other units can fire as many missiles per turn as the skyray has as long as they can get markerlight hits.

That is to say, there is no limit to how many of the skyray's missiles may be released per turn, but each one requires a markerlight hit from any Tau unit.

That means, a Skyray can fire six missiles per turn provided that there are six markerlight hits?

Yes.

Although you may want to use some of those ML hits to reduce your opponent's cover saves a bit first.