The default situation is that the use of an engine (or any other method) for propulsion while racing (therefore, at any time between the preparatory signal and finishing and clearing the finishing marks) breaks rule 42.1, Propulsion: Basic Rule. In the racing rules, there is no alternative to retirement when a boat realises that she has broken rule 42, and no option other than to disqualify a boat that is found by a protest committee to have broken rule 42, unless some other penalty applies.
Rule 42.3(h), Propulsion: Exceptions, allows various sorts of force to be used to get clear after grounding or a collision, but the use of a propulsion engine is explicitly not permitted.
Rule 42.3(i), Propulsion: Exceptions, allows sailing instructions to state specific circumstances under which a boat may use an engine, or any other method of propulsion, provided she does not gain a significant advantage in the race.
Note that rule 42.3(i) requires that permission given under that rule is given in the sailing instructions. The permission may be repeated in the notice of race if appropriate
When a race committee does not want a boat that uses her engine in this way to have to retire, there are two options:
Include a rule in the notice of race or sailing instructions to permit a boat which uses her engine to get clear after grounding or a collision to take a penalty that is less than disqualification. Examples of a suitable penalty could be a scoring penalty or a time penalty.
Suitable wording might be:
“When a boat uses her propulsion engine to get clear after [grounding] [or] [a collision], she need not retire, provided that she stops using her engine as soon as she is clear, but shall instead accept [a [ __%] scoring penalty calculated as in rule 44.3(c)] [a ____ penalty and notify the use of her engine to the race committee within the time limit for [protests] [declarations].”
Note that this does not change rule 42, which is forbidden by rule 86.1(b).
Alternatively, a sailing instruction may give permission under rule 42.3(i) for free use of an engine to get clear after grounding or a collision.
The sailing instruction should state whether the exemption applies to grounding, a collision or both. Suitable wording might be:
"A boat may use her propulsion engine to get clear after [grounding] [or] [a collision] and shall stop using the engine for propulsion as soon as she is clear."
Rule 42.3(i) requires that the boat does not gain a significant advantage in the race. In this context, use of the engine only to get clear does not constitute a significant advantage, even if the boat would have lost many more places without using the engine, and even if she can get clear more quickly than a boat with no engine.
As permitted by rule 42.3(i), a suitable sailing instruction might be:
When a boat needs to avoid commercial shipping, or needs to comply with the IRPCAS or government rules to cross or depart from [a shipping channel, zone or lane] [the………], she may use her engine or manual propulsion to do so. When she initially gains a significant advantage from this propulsion, she may continue to use the propulsion to remove that advantage.
The boat shall report in writing to the [race] [protest] committee within the time limit for [protests] [declarations], stating the time when use of the engine or manual propulsion began, the course and speed made good under that propulsion and the time the propulsion ceased. [A copy will be posted on the official notice board.]
When a protest committee decides that the only infringement by a boat that is protested for breaking this rule was that she gained a significant advantage, the penalty will be at its discretion.
When the race committee receives a report or declaration that propulsion has been used, it should protest the boat if there is a possibility that the applicable rule was broken, or that significant advantage may have resulted.
If in doubt, it should protest.
If there was good reason to use the propulsion, but the gaining of a significant advantage was unavoidable and was not corrected, it would be appropriate to apply a time penalty or scoring penalty calculated to negate that advantage, provided that the sailing instruction specifies a discretionary penalty.
However, if a means of propulsion not permitted by rule 42.1 or the sailing instruction, or if propulsion was used in circumstances that are not permitted by the sailing instruction, the appropriate penalty is disqualification.
If it is desired to allow this under rule 42.3(i) (perhaps best suited to less formal evening racing), the following sailing instruction is suggested:
A boat may use her engine after her preparatory signal in order to get to the starting area, provided that before she starts, she stops using her engine for propulsion and then takes a penalty by [making a complete 3600 turn] [some other provision].