It beggars belief. A Tucano collided with a Police helicopter near Wookey in Somerset in 1997 and still nothing has been fitted to RAF jets.
Err, Tucano has got TCAS I fitted - for about the last 10 years or so! See page 6 of the following link:
http://www.raf.mod.uk/downloads/RAFp...a_vol3_no4.pdf
As for Typhoon, it rarely flies at low level as it p!sses fuel out the back! It has a good air-to-air RADAR that allows it to detect other aircraft and this is coupled to an interrorgator that can detect Mode A (Mode 3) and Mode S. It has an IRST that can also spot anti-col lights, engine heat and aircraft-in-poor-weather. So TCAS would only really augment a good amount of sensors anyway. Also, as some have already pointed out, TCAS will only detect those that transpond - the primary means for all aircraft avoidance in Class G is 'See and Avoid' until the Air Navigation Order mandates transponder carriage in all aircraft in Class G. The lookout in Typhoon is better than many FJs.
So I would say that this is a nice-to-have rather than a must-be-fitted item. I applaud AVM Dick for raising this, but if it means slowing up operational capability (like a full weapons drop clearance), and there is a finite pot of money, then TCAS/ACAS should wait in my opinion.
Lj