Good news: I'm working on some automatic testing of the 'core' FG pieces, especially those I'm likely to break in my Navaids / airports / runways work
Bad news: I already broke something, in my runways refactoring. (But my tests caught it!)
Attached patch fixes it - it's (of course) the stupidest thing in the world. Incidentally, standardising this kind of code into some (inlined) header is becoming more and more of a priority for me - I've lost count of the number of times I've seen the 'clamp heading to 0..360.0' and 'reverse a heading and clamp it' idioms in the code. The KLN89 and MkVIII code have (of course) their own helpers for this.
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