HK AIR TRAFFIC CONTROL BLOG

[The Bald Innocent]

Speed Control

SMOC

Yes we do use speed control including speeding up and consider aircraft type in order to get the job done.

In the case you mentioned against the VMMC Departure I am not sure if it is the only factor which limited your climb with speed control.

However I would like to point out that according to the standard procedure regardless if you are departing from VMMC or VHHH if you are going on the same route e.g. via OCEAN to ENVAR the departure controller shall give 10NM in trail and no catch up to the next sector at OCEAN.

As you mentioned the VMMC departure is probably much higher then those from HK the TAS/GS would be significantly different and that adds complexity to how to achieve the requirement stated above.

The alternative is to step climb you below the VMMC Departure which requires agreement between the Departure Controller and the Area Controller in the next sector. This doesn't not always work as the VMMC DEP may need a lower level while you need higher. (the planned cruise level going into to TPE control in your case; note there is always level restriction going on different route downstream and destination) in this case the area controller may vector or give direct track to create "space" for the one below to out climb the one above.

Now to put this into reality the area controller may be controlling 20 or 30 aircraft at the same time this would be easier said then done.

Here is my question regarding using TCAS to displaying traffic on your ND, how much do you see and how do you interpret ? I always have a feeling that pilots would use them to guess what cause a restriction however in some case what cause a restriction may have nothing to do with what you see.