Rather think of it as a dice role per plane with a chance distribution depending on your settings.
So if you have a 20 plane unit and have 50% set to search, it would look similar to this:
Plane 1: IF rnd(100) > 50 THEN fly search mission
Plane 2: IF rnd(100) > 50 THEN fly search mission
Plane 3: IF rnd(100) > 50 THEN fly search mission
Plane 20: IF rnd(100) > 50 THEN fly search mission
Plane 21: IF rnd(100) > 50 THEN fly search mission
Answers all three of your questions at once.
PS: I am not completely sure if the above is correct as I do not have access to the code, but from observations
it pretty much looks like this is the explanation.
I'm not convinced this is how it works.
Today in digging around the forum to find a relevant thread to someone else's query, I came across the following thread.
In post #2, michaelm did not explain the difference in flying AM and PM searches in terms of a discrete dice roll applied to each plane. The way I read that thread, I would answer the OP that a 50% naval search assigment in a 20 plane airgroup leaves 10 planes tasked solely with naval search. The number which would fly in the morning is determined out of the ready number of airframes plus other factors such as weather.
Alfred, as always, thanks for digging up the most interesting and informative threads. Very good info here, didn´t know about the navS range
dependencies on AM and PM phase.
I agree with you that Michael´s response suggests a model where the percentage of planes assigned to a specific mission is calculated based on
total ammount of planes, but as far as I can see this is only an interpretation of a short comment not directly related to the specific questions raised
If this is the way the game engine handles mission percentages, this leaves the question open in what way an odd number influences results of a 50% setting.
Since my observation is, that on 1 plane squadrons there is no reliable way to determine when the plane will fly with 50% settings (for obvious reasoins I cannot
exclude external factors from these observations) or when it stays grounded, this seems to hint it is not governed by a simple rounded up or rounded down
Agree that it isn't a simple rounding up or down issue when percentages result in fractions of airframes being "assigned" to a particular task. Of course the issue is compounded when one is talking about a single airframe unit.
There are however two hints provided by michaelm as to what happens with integer fractions. The first is found in post #3 of this thread.
The other hint was made in the context of flying night missions where michaelm noted that the checks which include a 25% flying reduction do not apply to squadrons with 3 or fewer planes otherwise those squadrons would never fly as the implication is that they would never return an integer otherwise.
These two hints suggest to me that there is a fallback minimum threshold limit applied to really small units to allow the main assigned mission to be flown. That mission might not be flown on a particular turn as pilot fatigue/airframe maintenance, weather, supply, airfield runway damage etc are then factored in.