If I've understood Wikipedia correctly, what it's calling "Phase 2" of the Hawk missile program [0] is when some vacuum tubes were replaced. There are 12 count

If I've understood Wikipedia correctly, what it's calling "Phase 2" of the Hawk missile program [0] is when some vacuum tubes were replaced. There are 12 countries (including some rich ones) listed as using the Phase 1 upgrade of the missile, which is presumably still full of vacuum tubes [1]. This is the 30 year old upgrade to a missile developed 60 years ago. [0] https://en.wikipedia.org/wiki/MIM-23_Hawk#Development https://en.wikipedia.org/wiki/MIM-23_Hawk#Development [1] https://en.wikipedia.org/wiki/MIM-23_Hawk#Phase_I https://en.wikipedia.org/wiki/MIM-23_Hawk#Phase_I