Engines -
Sorry for the intrusion here - I'm having real trouble understanding the logic to buy less engines than airframes. OK a small flying school wouldn't have complete spare engines knocking around, and an airline will have alternative arrangements for a large podded engine or 3.
But surely the slight expense of having say 35 complete engines (not withstanding the fact a specific weakness as mentioned across all of those engines) stored ready to swap would be a nice hedge. Especially for Military flying training where the usage profile is much more aggressive.
My mental hourglass icon is on overdrive. It just doesn't compute.