The designated typhoon warning centre of the Far East Air Forces respon- 

 sible for typhoon warning in the Pacific area is located at Harmon Air 

 Force Base, Guam, Marianas Islands, and sub-centres are located at 

 Clark Air Force Base, Luzon, Philippine Islands ; Kadena Air Force 

 Base, Okinawa, Ryukyus Islands ; Haneda x\ir Force Base, Honshu, 

 Japan and Hickam Air Force Base, Oahu, Territory of Hawaii. 



The typhoon centre is responsible for the initial detection of tropical 

 storms and for the preparation and distribution of advisories of tropical 

 storms and typhoons, the assignment and transfer of forecast responsi- 

 bility to various sub-centres, forecasting the position and direction of 

 tropical storms or typhoons and the preparation and distribution of 

 typhoon bulletins to weather stations, and of forecasts to major Army, 

 Navy, Air Force, and civilian agencies. 



Throughout this discussion the words " tropical storm " will be used 

 to describe all depressions where the wind velocity is over 27 knots but 

 less than 66 knots. " Typhoon " will be used when winds are over 65 

 knots. 



Once a tropical storm or depression is suspected over any particular 

 area the typhoon centre on Guam analyses all available data and decides 

 whether or not reconnaissance for the following day should be diverted 

 from a fixed track mission to reconnaissance of the suspected tropical 

 storm. Very close contact and co-ordination must exist between the 

 typhoon centre, the reconnaissance squadron and the appropriate naval 

 agencies in order that flight capabilities for the following day may be 

 determined and available aircraft utilized to the fullest extent. If an 

 intense tropical storm is suspected or forecasted, then the availability 

 of aircraft over a period of several days must be considered as the main- 

 tenance of aircraft flying long missions at high altitudes is difficult. 

 Therefore, conservation of aircraft in commission must always be 

 considered. 



If the typhoon centre decides that typhoon reconnaissance is required 

 for the suspected tropical storm and the unit is capable of such recon- 

 naissance, crews are alerted and the aircraft made ready for flight. Pre- 

 flight of aircraft, briefing of crews, and other preparations for a long and 

 hazardous flight require from two to three hours ; therefore, extreme care 

 must be exercised to ensure that sufficient daylight hours remain to pre- 

 pare for flight and then fly to the suspected tropical storm and complete 

 the required reconnaissance. Night reconnaissance has been attempted, 

 and with present equipment has proven not as satisfactory. It has been 

 the policy of the Air Weather Service in the Pacific to obtain two fixes 

 daily on tropical storms. To obtain the most complete information which 

 will better aid in forecasting movement and intensity and to furnish the 

 latest possible information concerning the location of tropical storms, 

 reconnaissance is normally completed in the early daylight hours and the 

 late afternoon. It is not unusual for an aircraft to depart at midnight 

 to complete early morning reconnaissance on a tropical storm ; neither 

 is it unusual for aircraft completing late afternoon reconnaissance to land 

 at midnight or the early morning hours. 



The choice of co-ordinates for reconnaissance over the area adjacent 

 to the storm centre will be governed by several factors such as opera- 

 tional limits of the aircraft, hours of daylight remaining, and the position 

 of the tropical storm as related to regularly flown tracks. The typhoon 

 centre or sub-centre requesting reconnaissance will generally request 

 certain areas to be reconnoitred adjacent to the storm centre before 



13 



