Airport BGL's

[Guest Richard Hill]

I want to place KCKB in it's correct location, it is about 1500 ft to the W/NW from where it should be. What #.BGL's Airpoirt and NavAid or better yet is their a program that will find a BGL one might need. I was planning on disasmbeling it to use within Airport for Windows to correct location of runway and errors in taxiways. Richard;

[Guest Richard Hill]

Dick;I have the actual CAD file from the engineers involved with the extension of RW-21 by removing the top of a mountain and filling in a valley a 3 year+ project. The exact center of North end 21 is N39:19:19.793 W80:13:23.813The exact center of South end 03 is N39:17:16.034 W80:13:58.362All I know is that TerraScene is very acurate and the highwat that runs along the west of the airport is at least 1100 ft futher to the WNW near the terminal building. their is an extending taxiway that runs ENE 1700 ft past the end of 21 to Fairmont State Collage Robert C Byrd Avation Tech School.As for elevation, I find no problem in this area as everything is flat in the area where the runway should be. Richard;

[Guest]

Hi Richard,Like Dick said, you have to be very carefull with data you find out there such as CAD maps and GIS data, it is very possible that the datum used in the CAD drawing and the datum used by FS are different. Especially with engineering projects it is possible they are using a local datum or projection. If so then a point on the CAD drawing won't appear in the same location in FS.Check to see if the datum is WGS84 or the datum is based on the GRS80 ellipsoid. Then you can be pretty sure you are getting reasonably accurate coordinates (depending on the map projection used).Cheers,Derek

[rhumbaflappy 113]

Hi Richard.The website link I gave displays the data for the airport. The principal runway is the first set of data. That data is exactly the data MS uses in FS2002. If it were not correct, hundreds of planes would be smashing into the dirt around the Harrison/Marion Regional Airport, both in the real world and in the sim."FAA INFORMATION EFFECTIVE 20 MARCH 2003" is displayed near the top of that page. The data is recent, accurate, and registered with the FAA. MS has placed the centerpoint correctly. It's possible it's length is wrong in the sim, but it's center refpoint is perfect.Almost all the centerpoints of runways in FS are located correctly, even though roads, streams , mesh... might be mislocated. MS uses the real world locations in the sim... the same info used for millions of flights world wide.It's been common practice for photoreal designers to use the runways as known coordinates when adjusting or placing their photoreal images. It's the one consistantly accurate thing MS has in the sim... that's why I thought there was something wrong when I saw your post, and that's why I checked the airport data on the web. As far as Terrascene accuracy, it depends on the projection and accuracy of the GIS data used to create it's image. You could have extremely accurate data, and still be horribly mislocated if the projection for the data is not simple Lat/Long projection. And the larger the area included in the data, the greater the mislocation becomes.The CAD data you refer to is probably expressed as equidistant... measured in feet or meters. This is not the projection required by FS2002. FS2002 needs data as equiangular ( simple cylinder or simple Lat/Long ), with lines of latitude and longitude at 90* angles and equally spaced. That means the CAD data would definitely need reprojection, and that appears to be the case. The CAD data may well be accurate, but with the wrong projection, it's wrong for the sim.Dick

[Guest Richard Hill]

Dick;You were right abouit the runway location it is RIGHT-ON! However the taxiways, and tarmacks ned corrected. I have Airport For Windows, and FS Scenery Creator. After at least seven attempts to upload a 107 and 93 KB immages I have given up. If you want to see what I mean you can email me and I will send them to you.Richard;

[rhumbaflappy 113]

Hi Richard.You might want to rethink moving a runway.First. Changing a runway's location or altitude will mess up FS.There are a lot of things to change to coordinate the sim. If you distribute the scenery, it could cause all kinds of problems for other simmers. FS is actually built around the location of runways.. and in that regard, they are pretty accurate as to the location and altitude. Which brings me to point 2......I don't think that runway is mislocated.http://www.airnav.com/airport/KCKBAccording to that source, the center of the runway is:39.2966389 / -80.2280833...going to the location, and fine-tuning the exact Lat / Long with TDFCalc3b, MS is exactly right in the location.( even the altitude is right on the money! )If you have deduced the location is wrong from GIS or aerial photo info, then that source is most likely either wrong, or at the wrong datum or projection for use with FS.Dick