During the modeling process, I have encountered several semantic issues related to SysML v2 and would greatly appreciate insights from experts in this area. I will use an example adapted from ARP4754B for illustration.

Suppose there is an aircraft-level function:

Action1: “Decelerate the Wheels on the Ground.”

This function may manifest differently under various operational scenarios. For example, it may include:

• Action1.1: In manual operation, braking force is controlled in response to pilot pedal input (with an input feature of pedal command).
• Action1.2: When autobrake is armed, braking force is automatically applied according to the preselected braking level (with an input feature of AFCS command).

In previous modeling practice using SysML v1, Action1.1 and Action1.2 were treated as specializations of Action1; that is, they were modeled as distinct specialized forms of the higher-level function Action1.

However, the introduction of the timeslice concept in SysML v2 has led to some uncertainty. According to the updated semantic framework, would it be more appropriate to model Action1.1 and Action1.2 as two TimeSlices of Action1, rather than as specializations?I would like to inquire whether this usage of TimeSlice is consistent with the original intent of the language designers in introducing this concept.