There is a free package available ‘Airport Design Editor’ by Scruffy Duck Software. This will enable you to edit the default airports to realistic measurements as well as adding infrastructure. Using Google Earth I roughly measured Guams taxiways (52.5 Meters) and runways (66.2 Meters) and modified them accordingly. Also Concreted the runways and some of the taxiways as they appeared to look and relocating all the taxi signs etc.

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