STAR waypoint duplicate altitudes

Hi All

Question I was pondering relating to STARs in general - why do some waypoints within a STAR carry over duplicate altitudes from the previous one, resulting in level flight for a bit? I.e. waypoint 4 in the STAR is “LCS01 @ 3000ft” and waypoint 5 is “LCS02 @ 3000ft”…

Given one of the intentions of STARs is to avoid terrain, traffic & buildings, wouldn’t it make sense to always keep aircraft in a gradual descent that essentially keeps them higher during a STAR approach & thus less risk of danger, than level flight between STAR waypoints which brings them to a lower altitude sooner, more risk, & more fuel burn?

I’m sure I’m missing something obvious…

Thanks
George

They’re simply for a generalized altitude for traffic flow and a stabilized descent, setting you up for a better approach. Double altitudes are sometimes also used to avoid obstacles as well as traffic.

Read @tomthetank’s message for a more in-depth explanation :)

The procedures in Infinite Flight aren’t exact replicas of their IRL versions. Procedures will sometimes specify exact altitudes, but can also specify floors or ceilings. When you see two points in Infinite Flight with the same altitude, it’s possible one or both of these should read “at or above ” rather than specifying an exact altitude you must meet. It’s also possible that, for whatever reason, ATC wants you flying level for a bit.

Nonetheless, procedures are designed with a lot of safety factor in mind, so being lower doesn’t necessarily mean more risk. Basically all the risk is mitigated by following the STAR (even if you’re at the lowest point of an at-or-above waypoint).

A lot of procedures in the US are available through airnav.com. Check them out!

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Very clear, thanks Tom!

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