238 THE NEW WORLD OF SCIENCE 



this condition of affairs. The squadron commander could keep 

 in communication with all his planes, so long as they did not 

 get out of the telephonic range from him of say 5 kilometers. 

 A voice-commanded squadron then becomes a new fighting 

 unit of greatly improved power of manoeuvering. In practice, 

 it is customary to give a complete sending and receiving radio 

 set to the squadron commander; but to give only a receiving 

 radio set to each subordinate plane. The subordinate officers 

 can then receive orders, but have no means of answering back. 

 When an order to the squadron is given by radio, during flight, 

 the planes acknowledge it, each in turn, by a quick dip to 

 apprize the commander of their acceptance. If, however, a 

 plane fails to get the order, it gives a " wriggle " laterally, 

 which indicates to the commander that the order should be 

 repeated. 



Another great advantage of a voice-controlled airplane 

 squadron is that if a warning comes of a threatened attack 

 from a distant but rapidly approaching hostile squadron, the 

 airmen on duty at the hangar can instantly board their planes, 

 get off into the air, let out their air wires and commence climb- 

 ing to the altitude of expected attack, without waiting for 

 detailed instructions, which can reach them later by radio as the 

 situation develops. In this way, precious moments needed for 

 climbing can be utilized without loss of manoeuvering power 

 or adequate information for defense. Many a hostile airplane 

 has thus been intercepted and overthrown, that could otherwise 

 have probably dropped its bombs on an undefended target. 



Improvements in Radio Goniometry, or Direction Finding, 

 during the War. The invisible electromagnetic waves of radio- 

 communication radiate out in straight lines from the transmit- 

 ting station over every direction of the compass, like the rays 

 of light from a lamp or an open fire. Indeed, these electro- 

 magnetic waves are agreed to be identical with light waves 

 except in regard to their length. Whereas the waves of light 

 that are visible to the eye are only a fraction of one micron, or 

 one millionth of a meter, in length, the waves of light which 



