Global Transportation 95 



The absolute altimeter sends out an ultrahigh-frequency 

 signal vertically to the ground and picks the signal up as it is 

 reflected into the air. In addition, part of the signal is trans- 

 mitted directly from the sending to the receiving antenna. 

 The difference in time between the reception of the direct 

 and reflected signals serves to give the pilot his exact altitude 

 above the ground at all times. 



Mr. Sarnoff described Radar (Radio Detecting And Rang- 

 ing) as a great offensive and defensive weapon in wartime 

 which will, in peacetime, assure both air and surface craft 

 safe passage in any weather. Radar, plus the rapid improve- 

 ment in blind or radio beam flying, should ultimately make air 

 traffic almost 100 per cent foolproof. 



The Finest Airways System on Earth 



No other country in the world has an airways system to 

 match that maintained by the Civil Aeronautics Administra- 

 tion (CAA) . Early in 1943 the CAA was operating three hun- 

 dred and eleven lighted intermediate (emergency-landing) 

 fields, one hundred and forty- two flashing beacons, and 2,098 

 rotating beacons along the Federal Airways System within 

 the United States. 



For the benefit of all airmen (not just air lines pilots) the 

 CAA maintains and operates four hundred and eight inter- 

 mediate-frequency radio range and marker stations, one hun- 

 dred and ninety-seven ultrahigh-frequency radio fan markers, 

 and seventy-two ultrahigh-frequency radio range stations 

 (which probably will be increased to one hundred and forty- 

 three during 1943). Also in the airways system are four hun- 

 dred and forty-six weather-reporting stations, joined by a 

 54,000 mile teletype circuit for quick reporting of meteorologi- 

 cal conditions from coast to coast. Traffic from point to point 

 along the airways is directed from twenty-three control sta- 



