This question relates to ERS H.1.1 This is the clause that, in short form, says…
The Racing Rules of Sailing require us to use boats that have certificates and which comply with those certificates and their class rules. The class rules require the certification of equipment before a certificate for the boat can be issued.
However, club members by mutual consent may (for purely club events) ignore any part of the various rules they use. Having said that many clubs require members to have certified boats before they enter club races. Some rc sailors may not wish to belong to a club where a majority choose to ignore rules that do not suit them for one reason or another. Something to take into account before throwing the rule book out of the window, perhaps.
