Re: Aviation authorities at one time issued $\qquad$ guidelines for hobbyi
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02 Feb 2025, 13:31
OFFICIAL EXPLANATION
Discretionary, voluntary.
"Aviation authorities" issued "guidelines," or "recommendations," but there is an "absence of definitive laws." The guidelines are not legally required; rather, they are "voluntary" or "discretionary." "Firm" and "unvarying" are the opposite of what is needed. "Insufficient" goes too far-there is no judgment that the guidelines were "not enough," just that they weren't definitive. "Regular" is a versatile word that can mean everything from constituting a pattern to happening habitually or happening frequently.