Originally Posted by
Roger That
It’s a question that comes up regularly for this airspace .... notwithstanding the safety arguments for, and against, this approach as these can be assessed .... a key factor is often quoted as being the airborne database size necessary to hold all waypoints versus the fleet capabilities at any one time as there’s quite a lot of metal around that measures memory capacity in kb and mb, and not gb. There’s also logistical issues with separating the 5LNC points given the variety of city pairs here too and proximity of similarly spelled and sounding points at other ends of the NAT.
Also, bear in mind that this airspace is managed by the ICAO NAT Systems Planning Group .... they know very well how often a wrong coordinate is flown etc.
Finally, automatic systems are implemented that check your route using the confirm assigned route message, and a great deal of this airspace is surveilled using space based ADS-B with very frequent updates and route adherence checking (so ATC know before you enter the airspace that your route matches what they’re holding, and if you change route, track or level, they get an alert within seconds of it being input into the MCP - depending on ADS-B equipage - so that they can intervene).
Roger T - Thanks for coming back! Good to see this is discussed!
The following is just opinion of course...
The database size is I think a red herring. All the waypoints used are effectively waypoints in our databases anyhow, so to change '5650N' to 'WHALE' or similar wouldn't take any extra storage. But going to the named waypoints I think has some good benefits...
Data Entry - One night, I listened to an A380 who'd clearly made a data entry error going on to PBCS track be refused entry onto the track by Gander as they were headed to the wrong waypoint. I think they were headed for something like 56N050W and they should have been going to 5630N050W. Looking later on flightaware the aircraft took 3 (+?) large loops prior to getting it right. I felt for the Gander controller in this instance for having to deal with it (he was v.good) but also for the crew because the database doesn't help in these circumstances - If their's was like ours, then 56N050W is 5650N and 5630N050W is N5650 (I think!). See how easy that is to mess up? (we are encouraged upon reroutes to use the full lat/long rather than these short codes...) If the Gander Domestic controllers or Shannon controllers think we always forget to mention the '30minute part' when manually reading back the next waypoint when going oceanic on a PBCS track, that's why. You look at the waypoint name in the FM(G)C and it just doesn't say '30minute' to us... A waypoint name would be so much easier, and less RT.
Next is capacity - We can't take a reroute to a 30minute PBCS track unless the route is datalinked to us. If the points were named and thus the chances of data entry minimised, then we probably then would be able to. When the capacity gets going again, wouldn't that be useful?
It's late, think that's enough thinking for now! Thanks for engaging...