Definition
A phrase used in FAA regulations and procedures to indicate that the rule, requirement, or restriction being stated may be set aside when a different authorization has been issued. The alternate authorization may come from ATC, a waiver, a letter of agreement, an exemption, or another provision of the regulations.
Plain English
It means: this is the rule, unless someone with proper authority has told you something different. If you have a valid permission that overrides the rule, you follow the permission instead.
Context Anchor
Seen in FAA rules, AIM procedures, chart notes, and operating limitations where a normal requirement has possible approved exceptions.
Derivation
From 'otherwise' (in another way, differently) and 'authorized' (formally permitted by someone with authority). Together the phrase means 'permitted in a different way' — i.e., a recognized exception exists.
Why Pilots Care
Tells the pilot when a deviation from published procedure or regulation is permitted and under what condition, preventing both unauthorized actions and unnecessary rigidity when clearance has been given.
Intuition Check
Do not read this as “do something else if it seems reasonable.” In FAA use, it means a different action is allowed only when an official authorization specifically allows it.
Example Sentence 1
The regulation prohibits flight below 1,000 feet over congested areas, except as otherwise authorized by the Administrator.
Example Sentence 2
Flight below 500 feet AGL over congested areas is prohibited as otherwise authorized by the Administrator.