Why are non precision approaches not lined up?

Greg Farris wrote:
The title just about says it - I've always wondered WHY many
non-precision approaches (not talking about LOC only here, but VOR,
VOR/DME, NDB etc) are not lined up with the runway heading. Sometimes it
looks as though the approach desginers have gone out of their way to
make sure the non-precision approach is just a few degrees off - as if
to say - "look stupid - this is not a precision approach . . ." But if
this were so, then we would have to wonder why SOME of these approaches
ARE lined up and straight-in. I'm surev there's a simple explanation
that will be pointed out here.

It is due, at least in the cases I've seen, to the location of the
associated navaid, be it VOR or NDB. Sometimes they can't be sited on
the extended centerline of a runway, or possibly the navaid existed
prior to the airport. Aren't most GPS approaches lined up with a runway?


Matt