Blue Angels Question(s)

Our family went to the airshow in northern California last weekend. It
was a blast, to say the least. It blows me away to think about the
things people can do with planes and that they can have the
where-with-all to pull off some of the manuvers they do, and under the
G's they are pulling at times!

The Blue Angels were incredible, as were the rest of the performers,
but I left the show, as I'm sure others did, scratching my head
wondering how they do some of the things they do without tragic
results.

I heard that in some of the tight formation flying, they get as close
as 18 inches to each other. If this is true, and I have no reason to
believe it isn't, I have to wonder if they ever bump into one another?
If they were to bump into one another, would that be catastrophic, or
would they merely make contact and separate back into position? They
are all flying in the same direction, and at the same speed, so it's
conceivable that contact could be farily incidental.

Another question I had was regarding two Angels flying in opposite
directions and crossing by each other at a combined speed of 800 mph.
Do they have equipment on board that gives them precise situational
awareness, or do they use ground references? My thought was that one
of them could be lined up to fly right down the runway center-line, and
the other could line up just outside the runway which should guarantee
separation??? Their timing, so that they cross right at midfield is
amazing!

They put on an incredible show, and I'm glad my kids got a chance to
see them. I hadn't seen them in about 20 years, so I forgot how much
fun they were to watch.

Best Regards,
Todd