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Old 08-25-2010, 02:00 PM
Richard Pearse Richard Pearse is online now
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Originally Posted by qpw3141 View Post
Originally Posted by Richard Pearse View Post
I'll explain more about the document. It's not a regulation as such. The rules of the air in Australia are set out in a number of regulations. These regulations often have get out clauses such as "unless authorized by the Authority...". One of the means for the Authority to authorize various things and to expand on the regs is the AIP which is a manual for pilots that provides a mixture of mandatory practices based on the rules, recommended practices, and general information of use to pilots. It is this AIP that has the fuzzy language such as "should". Although it is tied in to the rules it is probably not the type of legal document you guys are thinking of.
I suspect that's common with aviation legislation.

Because virtually any rule can be broken if necessary to ensure the safety of the flight they probably steer clear of 'shall' for situations where the rule can legally be broken for safety reasons.

It's a long time since I did my Air Law exam but I'll try and dig out some of the texts.
That's a good point. Generally mandating an action is ok because, as you point out, any rule can be broken for the purposes of avoiding a fiery death, but I think "should" is used when you may use your judgement to do something if, in your opinion, it is just safer.

The example that started this is that the AIP says that aircraft should complete their turn on to final no lower than 500'. Because they use "should" I can come up with several everyday reasons why you might not follow that guideline (not practical given the terrain for one.) If instead they'd used "shall" then the only time you could break the rule would be to avoid turning into a fiery wreck. So if the terrain made it impractical or impossible to complete the turn at or above 500' you simply wouldn't be able to operate into the airfield.