For a 137 frontline aircraft, seven squadron Typhoon fleet, plus in use reserves, to last the 25 years they are supposed to, you apparently need 232 aircraft. If we go down to six squadrons you could cut the total by 30 jets, or so (smaller training requirement etc.) but to trim many more, you'd be looking at a substantially smaller force or a shorter life. And our boxheaded chums definitely want all 180 of theirs, and may even exercise an option for a few more, so if we cut back, the penalties and workshare implications won't be nice.