> "we have an aircraft en route to enter UK airspace and we don't know when or where - stop planning more flights until we know where that plane is".
Flight plans don't tell where the plane is. Where is this assumption coming from?
Flight plans don't tell where the plane is. Where is this assumption coming from?
In this regard UK ATC can choose to do anything they like with a plane when it comes under their control - if they don't consider the flight plan to be valid or safe they can just instruct the plane to hold/divert/land etc.
I'm not sure the NATS system that failed has the ability to reject a given flight plan back upstream.
I have no idea what percent of the volume into the UK comes from outside radar control; if they asked a flight to divert, that may open multiple other cans of worms.
Any ATC system has to be resilient enough to handle a diversion on account of things like bad weather, mechanical failure or a medical emergency. In fact, I would think the diversion of one aircraft would be less of a problem than those caused by bad weather, and certainly less than the problem caused by this failure. Furthermore, I would guess that the mitigation would be just to manually direct the flight according to the accepted flight plan, as it was a completely valid one.
One of the many problems here is that they could not identify the problem-triggering flight plan for hours, and only with the assistance of the vendor's engineers. Another is that the system had immediately foreclosed on that option anyway, by shutting down.
That doesn't matter, because the previous unit actively hands the plane over. You don't need the flight plan for that.
What does matter is knowing what the plane is planning to do inside your airspace. That's why they're so interested in the UK part of the flight plan. Because if you don't give any other instructions, the plane will follow the filed routing. Making turns on its own, because the departing ATC unit cleared it for that route.
I thought practically, what's handed over is the CPL (current flight plan), which is essentially the flight plan as filed (FPL) plus any agreed-upon modifications to it?
> Because if you don't give any other instructions, the plane will follow the filed routing. Making turns on its own, because the departing ATC unit cleared it for that route.
Without voice or datalink clearance (i.e. the plane calling the new ATC), would the flight even be allowed to enter a new FIR?