also, some Ukrainian pilots might be brought up to speed on US jets relatively fast:
https://www.aerosociety.com/news/ukraine-time-to-fast-track-front-line-fighter-pilot-training/
A: Conversion to a front line combat aircraft for a new pilot would usually take about six months to become limited combat ready. However, a more experienced pilot would take less than half that time, and someone requalifying on type after a break would only take a few weeks. If operational reasons demanded, then a much shorter course for experienced pilots learning a new type, focused only on the relevant tactics and weapons, could be done in four to six weeks, much of which could be done on simulators.
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A: I don't agree that aircraft 'gifting' crosses a fictional red line, so I have struggled with the approach taken by some nations. For example, if giving an aircraft purely capable of the air defence role, why is that seen as an offensive weapon? If we subscribe to the concept of collective defence and have decided that we will arm Ukraine in their struggle against a ruthless and overwhelming enemy, why would we wish to tie one hand behind their back? Of course Russia wouldn't like it, but that is because they fear the impact of airpower, which is exactly why we should do it. Action is long overdue.