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Elevated airports?

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Hope someone can help:Recently I bought Raimundo Taburet's Mesh files for Central and West Europe and installed them.Looks good, however...have a look at the picture.It's Arnsberg Apt. which now shows extremely elevated.I've seen this with dozens of other (mainly smaller) airports.The all seem to be situated on a kind of 'mesa' ;)Anything I did wrong?- Gideon (EHAM)

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Hi Richter36.You didn't do anything wrong. Taburet's mesh simply wasn't corrected for the FS2002 airfields.All airfields for FS2002 have flatten coding as part of the airfield. This coding is 'tuned' to the default FS2002 mesh elevations. If the new mesh is not at the same elevation under the airfield, you'll get a mesa or a pit. Payware or freeware mesh will do this. If the mesh is not 'corrected' to the default airfield elevation, then the fix is to write a new flatten command to lower ( or raise ) the airfields. Some mesh authors include a set of airfield correction bgls with their mesh. Perhaps, Taburet did not.If so, your money wasn't enough to pay for the extra work of the necessary flattens. In that case, you could try ask for a refund. Or you could learn SCASM code ( or the new TMF flatten code ), and write your own. Sorry.

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Hi Richter36.I didn't mean to imply the mesh is 'wrong' or does not look good. This airfield altitude problem does affect all 3rd party mesh, freeware or payware. Microsoft must have spent many hours setting the altitudes for the default airfields... and did a decent job, overall. If Ray were to include all airfield altitude corrections for this mesh, it could mean thousands of corrections, and would cost him dozens, or hundreds, of man-hours to accomplish. He probably would not even sell his mesh, as the price would get too high to cover his labor costs. Oddly, the more detailed the mesh, the worse the problem may get! And Ray is right, in that the 'correction' may leave the appearance of the airfield looking strange, as one end may lie in a pit, while the other sits on a plateau. Again, M$ seems to have done a decent job, here, considering the airfields must lie flat.Don't expect freeware mesh to be any better in this regard. Some authors will include altitude corrections; most don't. The only advantage for freeware, is that because it is free, you don't lose anything for your disappointment, except download and installation time.

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Dear Rambaflappy, You are very much right on your last post - regarding the hours of work which will go into that kind of job. Furthermore we must consider - the extension which the mesh scenery covers - the bigger - the more work. For instance - in that kind of mesh of Eastern Europe - which covers Such a vast area - therefore there are quite lots of airports in that area. It will be feasable - to improve - that kind of problem in mesh which covers only - strecthes of terrain - or country partial coverage - where you have to deal with just few airporsts - But of course - somentimes - simmers do email me and let me know that some airport can be badly affected - if it is too much then can find the remedy - of course if possible. We see what happen with fs2004 - I heard that can be the sim which will provide solution to these problems - but right now is just words I heard - I rather see it with my eyes to believe. By the way - have fun Ray (Ps. What does it mean Rhumbaflappy??)

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Ok, so what you guys are saying is that there's no mesh available (commercial or freeware) that does not have this problem?Main cause: the huge amount of work to correct every flatten for each airport? Is that correct? Thanks for your extensive explaination on this issue so far!- Gideon (EHAM)

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Yes. Thousands of airfields for Europe alone. Each requiring a flatten code to make the field lie flat to the ground. The work would probably be too extensive for a commercial vendor... after all, he's trying to make a living wage from his work. You have to watch the man-hours invested. Ray has produced some great-looking mesh for our sim. He probably would not continue, if he couldn't make a profit from it. I understand his situation, and I don't find fault in it. Perhaps he could give buyers a warning about airfield altitudes, but no one else does this... and such a warning might leave the impression that his mesh is somehow inferior, when it is certainly no worse than any other mesh in this regard. If someone, payware or freeware, is willing to adjust all the airfields along with his mesh, then he should certainly advertise that! But, as Ray pointed out, altitude is only part of the problem. We also need to regard the slope of the airfield. Also, changing the altitude of the field itself may affect other aspects of the sim... leading to problems with navigation, landings, saved flights and lessons. In truth, the mesh would have to be adjusted... not the airfield, whether or not the airfield is correct.I give Microsoft a lot of credit for the look of the default... they matched the altitudes of mesh and airfields pretty good. But we're all stuck with the thousands of airfield elevations they left us.Hopefully, as Ray points out, FS2004 code will place airfields at mesh-relative ground level, and allow for the sloping of the field, itself. Or perhaps, better elevation data will become economically feasible worldwide. Designers for US mesh have an advantage here, as such data is already available. Accurate European data is horribly expensive, and sometimes not available. This means Ray, and other designers, must use exotic methods to produce a realistic-looking mesh. Some use oversampling. Some use altering of the input DEM data. The better the data, the better the resulting mesh, and the better the fit of the airfields, ( and the less need to alter the data or oversample the mesh ).

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HI Richard,Just to add a bit to your correct answer, probably 98% of the problem lies in FS200x's flat-runway limitation. The other 2% is most likely errata in Jeppesen's airport elevation/location database.I highly doubt that MS hand-coded many, if any, of these airport elevations. They probably just imported the airport elevations from the Jeppesen database.The problem lies in the difference between airport elevation and the threshold elevations of the airport's runways. I would dare to say that NO runway in the real world is perfectly flat, yet FS200x cannot depict anything BUT a flat runway. If you study the runway threshold elevations at Airnav.com, you will almost never find the same elevation at both ends of a runway. Meanwhile, the listed airport elevation is usually the highest ground elevation on the airport grounds, which in most cases something entirely different than any runway threshold elevation on the airport.The problem will not be too glaring in those places where the ground elevation doesn't vary by more than 15-20 feet. But in those areas where the ground elevation varies by a significant amount (two places come to mind immediately--Davis-Monthan AFB in Tucson and Tucson International), there is simply no getting around the problem. You can lower the airport to get rid of the mesa, but then you end up with a ditch at the other end. Danged if you do, danged if you don't.While a small percentage of these problems can be fixed by correcting the airport's elevation or location, most of them we just have to live with until MS creates the code to depict runways as they really are instead of perfectly flat.Justinhttp://www.fsgenesis.com


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Justin - Toposim

http://www.toposim.net

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Gideon>Ok, so what you guys are saying is that there's no mesh >available (commercial or freeware) that does not have this >problem? The Visual Flight UK & Ireland mesh doesn't have this problem. We've taken the view that as the airport elevations and locations in FS2002 are correct (this is certainly true for the UK & Ireland), they form a useful additional input into the mesh creation process.John FarrieVisual Flighthttp://www.visualflight.co.uk/

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John always ready to take opportunity to advertise his products! ehehe that is understandable.That is why - in Fs2002 airports altitudes and positions - are very often wrong! so if John Uk mesh display flat terrain around airports - that mean that the mesh is also wrong! Ray

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>John always ready to take opportunity to advertise his >products! ehehe that is understandable. Sorry, I thought it would be OK to provide a very short and factual response to Gideon's question. >That is why - in Fs2002 airports altitudes and positions - >are very often wrong! so if John Uk mesh display flat >terrain around airports - that mean that the mesh is also >wrong! FS2002's airport elevations in the UK & Ireland all tie in accurately with the official UK AIP information. As for position, some of the individual runways may be very slightly out of position or misaligned, but not so much as to affect the accuracy with regard to the mesh - the airports are in the correct location. I very much suspect this is the same in most of Europe, but I'd be interested if anyone has any examples where it's not the case.By the way, the Visual Flight mesh isn't flat around an airport if the actual terrain around the airport isn't flat in real life.John

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Well, I noticed it's a quite a 'political' subject :)The bitter pill still is:You buy a mesh because you (want to) fly VFR.VFR brings you mostly to the smaller, outback airports.Exacly those that didn't got the attention from MS. Not to blame them, but it is the case.Hence..mesh is nice, but don't go flying anywhere or you end up with quite some challenging 'Funchal' approaches.. ;)I will check out your mesh John. Don't have anything for the UK yet.cheers!- Gideon (EHAM)

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Well we can say - Uk has basically a mostly low elevation terrain - therefore those problem are more easy to fix - and also with some luck avoidable.But I do lots of 10 m mesh - experiment - and even 10 m dem - which are in absolute the best available - no matter what - 10 m dem is the most precise and accurate elevation data - available still get those problem in places - That is why - my opinion airport in fs2002 are not extremely well placed - and I've reports from pilots - where airports are often 500 m on the left or on the right - - How can you claim that mesh no matter who desing it - with what dem - can be accurate and fitting nicely into airports?? - If you editing the area - then the surronding mesh is not what it should be - cause you have change it to fit the airport nicely.Ray

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After looking at Visual Flight Scenery I considered that my local area was far better in Visual Flight than I could produce.This is the Vale of Evesham, UK.I was able to adjust my three airfields, that are not included in FS2002, to make the elevations fit into Vistual Flight scenery.I am now waiting for the proposed UK aerial collection so that I can add actual scenery to Visual Flight mesh and place my buildings, etc in the correct places.Versions of my local area for FS98, FS2000 and Fs2002 are at my website www.users.globalnet.co.uk/~ngo plus a special version for FS2002 for those with Visual Flight Scenery.

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Dear Ngo;Where is the Mesh on that pictures? Looks like the Padana Valley in North Italy!Try to do the same with 10 m usgs mesh - if you can -! the Real Mesh! Ray

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