Enroute planning when running short.
Hi Suzie,
A good question.
It is pretty rare for us to need to factor in a slick arrival to HKG, for fuel planning when enroute. But it does sometimes happen.
In over 700 long haul sectors, I can only recall having to send such a message to CX IOC (OPS) twice. Typically requesting FIR entry point to somewhere downwind with no altitude restrictions. (Example Elato to Sokoe)
This would probably have been sent when maybe halfway to HKG, with the fuel trend seriously "going the wrong way". Requesting a fuel conservation arrival at this stage is only one of various strategies we would be employing.
This can happen with a major "stuff up on flight levels", plus maybe something extra. One time we were stuck low, and then had to go off track (80+nm) for weather trans pacific. The other time, Mongolia would not let us enter their airspace, so we had to go all the way south to FKG and fly through China. At that stage we were obviously in serious fuel conservation mode, and looking very closely at our predicted fuel for arrival.
Naturally we were overflying airports on the way to HKG, but requesting a "slick" arrival helps us to plan if we are going to continue or drop into somewhere like Taipei etc. The decision to continue to HKG or stop for more fuel on the way is made by the Captain and his crew, if they consider it safe. Financial cost is not a factor.
In summary, the message from our Ops about "low on fuel", is simply us letting you know early that we may be unusually tight and have planned for a slick arrival. If you can't let us go direct, then please let us stay high or fly clean speeds, with no "expedite descent through......"
As always, if you can descibe your arrival plan then we can fly that as fuel efficiently as possibly. If what you describe does not sound good, then we can let you know what we need immediately.
There is a finite stage when we will declare a fuel emergency. Personally I will give you an alert in minutes. Example, "we need to be at LIMES for the approach in 10 minutes or I will be declaring a fuel emergency".
It is too bad that we never get to meet ATC anymore for "socials" or famil flights and talk about these issues. Guess that we are all kept far too busy working!
Keep up the good work!