Recoverability with HFS Plus following removal of a disk from RAID 0 hardware or software
In a RAID 0 set established by Disk Utility you, of course, have zero redundancy. The moment one of the drives is lost from the set the entire set becomes useless and you have a volume failure. If (and only if) no attempt was made by anything to write to the volume while the physical drive wasn't there you might be lucky and it will be OK but otherwise you will have a problem.

At that point any recovery is going to be difficult. Any attached Mac will just see the volume disappear. I've seen this happen a number of times and getting the data off was only ever partially successful (and a small part at that) and extremely expensive. My advice to a couple of customers who've had it happen is just give it up as a joke and go to the backups. Chances of good data recovery are so close to zero as makes no difference.

If you are extremely lucky and there was no attempt to write to the volume and the heavens smile upon you then it is conceivable that a volume repair might work. I've actually seen it happen - once.

For a hardware RAID 0 it's pretty much the same.

The only place I like to use RAID 0 is in a separate hardware drive array such as the Promise boxes for a user who really needs the speed for something like video editing.

If you really need the speed of RAID 0 then make sure you have really good backup policies.