Some Tory backbenchers have called for British military intervention in the Russian invasian of Ukraine (source). The specific proposal seems to be to deny Russia air supremacy (which Russia claims1 to have attained). Ignoring the potential for further escalation, I am wondering whether this is remotely within the British military capability.
Just to clarify terminology: Air supremacy is a degree of air superiority wherein the opposing air force is incapable of effective interference. (Thanks for o.m. for digging up the phrasing). Denying air supremacy to Russia is a significantly lower standard than trying to attain air superiority for a hypothetical interventionist.
1 It has turned out that Russia's claims of having attained air supremacy early in the invasion were exaggerated at the very least; with Ukraine apparently still capable of conducting anti-air defense and even air-to-ground assault on their own.