An index of air carrier two-letter codes is available, as are three-letter airport codes , U. S. Department of Transportation on-time arrival statistics and useful information on airline no-smoking regulations (provided by Action on Smoking and Health [ASH]). Some far more complete lists of air carrier home pages are maintained by M-D. Seidel , the Commercial Aviation Resource Center , and R. Muirden . Some pages with information and maps of individual airports are available. Here's an airport-to-airport distance calculator , and information about the Oakland Airport (OAK) and Frankfurt Airport .