How do designers determine the altitude profiles of neighboring procedures for deconfliction purposes?

Question

I am interested in studying ICAO's Continuous Climb Operations design strategy, however I have some trouble understanding how the procedure designers take into consideration the traffic flow from neighboring arrival procedures, in order to avoid conflicts with their proposed departure procedure (optimized for continuous climb).

Doc 9993 (Draft version) states:

1.1.5.3 Traffic Avoidance. In the most optimum situation, a departure route should be designed in such a way that there is no restriction that prevents an aircraft continuing its optimum flight profile. Both, the arrival (STAR) and the departure (SID) should be de-conflicted laterally or vertically. This optimum situation may not be reachable and therefore a balance must be found between the arrival and the departure routes.

However, even if one makes the assumption that an IAP has a somewhat self-explanatory altitude profile, at least where the glide slope interception begins, this is clearly not the case for STARs. There are charts which do not provide a starting altitude for their depicted arrival procedures, something that makes the estimation of the aircraft's altitude during the route traversal even harder. On top of that, there are arrival procedures that do not have any altitude constraint at all, such as GATBY ONE.

Anything that could point me into the right direction would be more than welcome.

Answer 1

I have some trouble understanding how the procedure designers take into consideration the traffic flow from neighboring arrival procedures

We don't.

We only concern ourselves with terrain and obstacle clearance. Doc 8168 Vol. II I-2-1-1 refers.

Deconfliction is an ATM responsibility, covered in Doc 4444.

Answer 2

In terminal areas with relatively low traffic levels, it may be simpler for ATC to let each flight climb or descend at their discretion, with verbal restrictions when an actual conflict appears. There is no point in trying to optimize these procedures because they're already pretty much optimal for the few flights that use them.

However, in busy terminal areas, conflicts may be so common that it becomes simpler to chart the expected restrictions and perhaps verbally remove them when a conflict doesn't actually appear for a specific flight. That doesn't mean you will see a restriction on every fix/leg, though, just the ones where procedures cross.