Moving slightly off topic and increasing:
The USN has started a program of warrant officer pilots and NFOs. Besides the usual medical qualifications, no older than 27, et al, the program is open to E-6 to E-9 (more senior enlisted) and upon completion are awarded CWO (chief warrant officer) rank.
Requires only an Associate's degree (2 year). Open cockpits include P-3, EP-3, EA-6B, helos. No pure strike jets like F/A-18.
First ones through the training pipeline should be joining their operational squadrons soon (if not already).
I would imagine US citizenship would be a requirement for this as well.