When the loop starts, n.type is still undefined, so the while statement
depends on unitialized garbage. The input operator cares for the [End]
bracket anyway (returns if the first character is a '['). So it is safe
to check for it after reading the line and break if necessary.
good as we can get" until we find a data source with actual VOR magnetic
offsets. We can use VOR offsets from some fixed date, but not all VOR's
were installed on the same day so no matter what date we pick we will be off on most of them.