TCAS is nasty at low level, we had a Fokker 50 that got "descend" command form TCAS on short finals due to a fighter passing overhead for break. Descend when you are 200ft AGL in a F-50.........
Think this has been fixed in the latest version though. (Not decend when below xxx-ft with gear down ect, doses not help you FJ lot a bit I should think
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