If aircraft 'miss', then TIBA has been effective
If pilots of 'possibly' conflicting aircraft ARE aware of and communicating with each other to arrange a 'miss' ... then, 'as ordinary as that is' (with possible closing speeds upwards of 900Kts) .. TIBA (as a last line contingency) has been effective!
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If either or both pilots do NOT know of the other traffic and therefore do not have a mutually discussed 'resolution plan' .... TIBA has NOT been effective in so far as 'luck' has played a substancial part!
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There is a world of difference between the two!!
