Further to my last TCAS is not fitted to any fast jets in RAF service and to be honest with the nature of our sorties would not be very useful. We seldom cruise at one level for any length of time and are rather dynamic in our flight profiles. However we instill a culture of lookout during training and have our eyes outside the cockpit for most of the time we are VFR submitting to the 'see and avoid' principle. On aircraft fitted with air-to-air radar we generally have radar contact on any aircraft at a suitable range to avoid you, ultimately relying on visual contact to preserve separation.