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StopStart
19th Jun 2000, 15:27
Bit of a query regarding slot times, delays etc prompted by our (very minor) delay yesterday. I'm an RAF C130 pilot and seem to spend most of life bimbling along between Lyneham and RAF Akrotiri in Cyprus. We go GAT along with the bucket and spade brigade and so are subject to the same slot times etc.

My query, then, concerns the allocation of slot times. Our flightplans are submitted for us by our Ops staff using the Jeppesen Jetplan they generate. Obviously we then fly the route generated on the ACK message but we don't always necessarily fly the planned FLs (depending on wind,fuel,time etc). I assume the slot time we receive is based on where we'll be, when we'll be there and at what FL; if we can go at at a different FL (or routing given weather and directs) how does the big computer generate such an exact (to the minute) slot time? Is it based on the forecast number of aircraft in any one sector at any one time or are there other factors at work? Also does our choice of diversion have any effect on our slot times at all?

Any light shedding would be gratefully appreciated. Thanks.

Findo
20th Jun 2000, 02:38
Yes and then no.

The European system is divided up into representations of each ATC sector complete with its dimensions and lower and upper limits.

It calculates the time you will take from take off to reach each sector. The capacity of each sector is recorded and when flow control is imposed then slots will be issued up to the target sector flow rate of capacity minus 20 %.

The buffer is for those running early and late bunching together.

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Go with the flow ... or you'll miss your slot.