Interpolation Logic

[JRBarrett 3,130]

Jim,If you would like to try the ASE Full, just e-mail me for the link.

Hi Jim,Very much appreciate the offer, but it's too late - I already purchased the full version. I don't mind at all, I've been enjoying HiFi products since way back to Active Sky 5, and have always upgraded via the less expensive (or free) "previous-user" option. For all the hours of use I've had from AS* products, it's worth it to pay full price.I really did a good hosing out of my files and registry entries - there was a LOT left over (in the registry) from all the previous versions.The fresh installation went well, and for what it's worth, ASE now loads much faster, and completes its depiction output to FSX in a much shorter time as well.Now.. for my discovery of the day - which, I think, is significant. After loading the "new" ASE for the first time, (once again with my aircraft parked at Heathrow) and setting my options, I went to the map screen, and noted that the "dots" indicating reporting locations were all blue in color. I quickly realized that the blue dots are "stations" (as opposed to "airports"). In my previous installation of ASE, I had only "airports" clicked to display on the map, but not "stations"... i.e. all the dots were yellow.So, I clicked on the option to display "airports" as well - so now I have both blue and yellow locations displayed.Here is what I found - many of the BLUE "stations" (that were using advanced interpolation) were, in fact, interpolating correctly, using actual nearby UK airport METARS, confirmed by entering their identifiers on the report screen, and clicking on "interpolation details".BUT!! The yellow "airports", by and large, were using incorrect interpolation, based on the infamous four African airports surrounding the 0/0 LAT/LON.There are exceptions. To follow along, please load an aircraft based at Heathrow, and set the map zoon factor to 50 miles.At the center of the map, I see EGLL "airport" in yellow, and very close by to the southeast, EGLL "station" in blue. Hovering the mouse over these, I see that both are reporting the exact same weather, based on the "real" EGLL METAR, which is winds 350@4.Just above Heathrow is EGWU, Northolt Airbase. Again, there is a blue "station" dot, and above it a yellow "airport" dot. Both dots are showing advanced interpolation - the weather is very slightly different, with the blue version showing winds 144@3, and the yellow showing winds 145@2 - both are using "African" interpolation.SW of EGLL is EGTF Fairoaks - stand-alone blue dot - but with incorrect African interpolation.West of EGLL is EGLM, White-Waltham, another stand-alone blue dot - but this one is using correct "real" interpolation.Every single yellow-dot "airport" is using African interpolation except for those which are associated with a blue-dot "station", which has the same identifier and which represents an actual METAR reporting location, or which are associated with a blue dot station (with the same identifier) which IS using correct. "real" interpolation.I then moved my aircraft within FSX to EGWU, mentioned above. My aircraft symbol on the map moved immediately to the new location, but nothing changed - both the blue and yellow versions of EGWU are still showing the African coordinates.Farther west, EGUH, High Wycombe - "real" interpolation.In summary, probably 80% of the blue dot "stations" are interpolating correctly, most with northerly winds (tonight). ALL the stand-alone yellow dot "airports" are interpolating incorrectly, with southerly winds. A very few yellow dot airports are OK, but only if they are associated with a nearby blue-dot station that is interpolating correctly.Of course, all blue-dot stations with actual current metars are correct.I just re-checked the ASE simconnect log. At no time has there been any indication of a loss of communication with FSX during this whole experiment.One other thing I noted. All the blue dot stations, have the full name spelled out when I hover the mouse on them, ie "EGLL - Heathrow, London, United Kingdom"... but the yellow dot airports simply say "airport" when I hover the mouse, i.e. "EGLL - Airport" - Same for all the other airports represented by yellow dots. I assume this is normal?Sory for the long-winded post, but I certainly find the mixture of correct and incorrect interpolation within a small area to be curious, and I hope this info is of help.Jim Barrett

[JSkorna 137]

Hi Jim,Thanks for all your detailed posts and your work on this. I will report this as a interpolation bug through our system for the programming team to look at.

[creppel 3]

Thanks for pointing this out Jim.I am in trouble too with these African stations. :(

[JRBarrett 3,130]

Hi Jim,Thanks for all your detailed posts and your work on this. I will report this as a interpolation bug through our system for the programming team to look at.

Jim, An update...I went online this morning at my usual starting location of EGLL. One difference between this test and my two previous is that the real-world surface winds across the southern UK were quite a bit more "brisk" than earlier in the week typically 10-15 knots as opposed to 3-4 knots - and coming from the WNW instead of from the east.While it is still true that the "interpolation details" for the standalone airports, (depicted in yellow on the map screen), continue to show the 4 African stations, I no longer think that said airports are actually using the African stations as their interpolation data source. Virtually all the advanced interpolation sites (yellow "airports" and blue "stations" alike) were quite consistent with each other - all showing West to Northwesterly winds, with temps and pressures consistent with the local "real" METAR sites like EGLL, EGKK etc. It's more obvious today, because the overall wind speeds are higher.In other words, it appears that the "bug" (if that is what it is) is only in the "interpolation details" function in ASE SP1 - but not in the actual application of interpolation. ASE seems unable to accurately report which four local METARS are being used for yellow "airports", but none-the-less, (internally), ASE is using local sources for the airports, despite what the "details" functions shows.Jim Barrett