just to share an experience and lesson learned yesterday from IR checkride. We filled 2 flight planes (my via autorouter, the other guy vie eurofpl) – the same aircraft, the same destination, the same STAYINFO and probably almost the same routing. Timing was coordinated, flight plans were not overlapping, both were showing in the system. But the weather was not cooperating – visibility 200m pushed our session to the right. So we both send the DLA to our flight plans. And here the funny part starts – the CFMU computer got confused by the DLA messages. What I didn´t consider was the DLA syntax – OKAER-LKKU1000-LKKU. So the CFMU computer has no idea which of our flight plans we want to push to the right. When driving to the airport I get a call from the tower and they told me the later flight plan had been cancelled and we have only the first one with corresponding DLA in it. We double check, everything looked fine. But some circa 45 minutes later, the CFMU somehow processed the DLA message 2 hours old (the intended DLA to the already cancelled flight plan) and moved the first flight plan into timing of the second. So when the first guy went for his flight there was no flight plan at the end. I went up to the tower and even we have both flight plans showing in the system the center was not able to issue and IFR clearance because it was not showing in their system. So we cancelled all the flight plans showing in the system – no matter we get responses from CFMU that such flight plan doesn´t exist – and file a new one with EOBT in 5 minutes.
Long story short – don´t fill two consequent flight plans for the same aircraft and the same routing, wait for the first aircraft landing and file only after that. the CFMU is really not able to handle that.
I had also funny situation flying from Sweden (Kalmar – airport withot immigration), landing in Graz for clearing Schengen and then continuing to Zagreb. I filed both flight plans before taking off from Kalmar. For some reason the flight plan wasn’t closed after landing in Graz and the second one wasn’t available to tower, so they didn’t allow me startup. Suddenly the plan appeared (after tower tried few times to close the first one) but with one hour delay. So they canceled it for me and refiled new one with EOBT in 5 minutes.
If you file one FP via Autorouter, that sits in it’s database and does not go anywhere, until time X.
If you file one FP via EuroFPL, that sits in it’s database and does not go anywhere, until time Y.
X and Y are determined by the FP filing system. I think Autorouter files them right away. EuroFPL I am not sure about; they may hold onto them until EOBT minus 24hrs or whatever.
Then Eurocontrol gets them and that is when any overlaps will get flagged.
Moreover, each country addressed (the addressing is done by IFPS) chooses when it gets the FP from Eurocontrol. This is normally EOBT minus 5 to 10hrs. So additional issues may get flagged at that point.
So if you do it “right” you can apparently file overlapping flight plans, but for sure they won’t have gone to Eurocontrol.
I have some notes on this here
With VFR, overlaps are OK because nobody (except those explicitly addressed) will see them, and there is no automated (or possibly any) process for detecting overlaps. There is no central database system for them (well, there is the S&R / national security database into which all FPs get copied but that doesn’t do any validation).
I guess we would had been alright – until we send the first DLA message. It would be probably ok by autorouter though.
