Question- Foreign Air Carrier vs Part 121
My colleague and me have a dispute about oxygen mask using when above FL410.
Our company registered in Taiwan, and have schedule round flight flight from to LAX, SFO. The key point of the dispute is: Should our company, a foreign air carrier, obey the regulation of 14 CFR Parts 121 ? We know Part 91 and 129, which are discribed in our FAA-issued opspecs. But, how about Part 121 ? which is much more restrictive to operation, and make no sence that's only applicable to US-regidstered air carriers. (My opinion is : YES, but my colleague says NO)