Couple of differences between the USA and Europe.
One of them being that becoming a Flight Instructor is a stepping stone for, I'll have to take a wild guess, 80-90% of the CPL trainee pilots in this country.
Translated this means there is NO shortage in FAA certificated flight instructors.
After 2001 the whole visa/work thing got really complicated and as fas as (FAA) instruction goes......forget about it not going to happen.
To be eligible for a H1B work visa you need exceptional skills which are not readily available with local job applicants.
JAA/EASA Head of Training Qualifications
JAA/EASA examiner qualifications
JAA/EASA Flight Instructor (unrestricted)
H1B visas are issued in a 2-week window every year in April and have a quota so if you miss the dead line or the quota is filled you need to wait a year.
Alternatively you could enroll with one of the very few schools in the USA that have a F-1 visa authority. After completing your training you can work another 12 months in your filed of study, ie instructing.
Now keep in mind the school has you by the cojones for that time and some of them don't pay.
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