This instrument has four major parts, a pressure-air-speed trans- 

 mitter, temperature-humidity transmitter, temperature-humidity 

 ventilator, and the recorder. 



(a) The pressure-air-speed transmitter measures the pressure of the 



atmosphere and the air-speed of the airplane, and transmits 

 these values to the recorder. The pressure unit is connected 

 to the static line, and the airspeed unit is connected to both 

 the static and pitot lines. 



(b) The temperature-humidity transmitter continuously measures 



the temperature and relative humidity of the atmosphere 

 and transmits these values to the recorder. The transmitter 

 consists of two transmitting units, one actuated by a bi-metal 

 thermometer and the other by a hair hygrometer. 



(c) The temperature-humidity transmitter is installed in a ventilator 



mounted outside the plane to the left and rear of the pilot's 

 position. The ventilator is approximately 18 in. long and 

 2J in. in diameter. 

 {d) The transmitters are electrically connected to the aerograph 

 recorder which makes a continuous record of all functions in 

 four colours, printing once a second on a 100-hour chart roll. 

 This recorder is located to the left of the bombardier's position. 



The radio altimeter, SCR-718, is mounted to the left of the 

 bombardier's position and is adjacent to the pressure altimeter to afford 

 rapid comparisons. 



The radar set x\N/APQ-13, modified to include an A-scope indicator 

 and a longer pulse length, is used on weather reconnaissance aircraft. 

 With this set the beam scans 360 degrees, as compared with only a 

 60-degree angle to the front on standard models. 



Another instrument now being perfected is a cloud scope for 

 measuring the base and tops of clouds and will probably be installed 

 in the near future. 



After all typhoon or storm reconnaissance missions, and in addition 

 to the post-flight summaries, all crew members give a post-flight 

 narrative of the flight with particular emphasis on their position. These 

 narratives are used in making changes in procedures, instruments, and 

 also are extremely valuable for typhoon analysis, and research as many 

 points are covered that the observer fails to record while flying in severe 

 weather conditions. 



Following is an aircraft commanders post-flight report of the ninth 

 mission flown reconnoitering Typhoon Beverly. The date was 7th 

 December, 1948. The aircraft commander was First Lieutenant David 

 W. Lykins, United States Air Force. I quote : — ■ 



Aircraft Commander's Report 



Vulture " Beverly "IX 

 7 December 1948 

 Aircraft No. 6450 



Crew A-1 was briefed at lOOOZ, 7 December 1948, to fly tropical storm " Bever- 

 ly," fix number nine, using a new method of reconnoitering the storm area. 



The operations office instructed us to climb to the 700 millibar level after take- 

 off, penetrate the " eye " of the storm, take a fix in the centre, then make a spiral 

 descent and sounding down to 1,500 ft. and proceed out of the storm on a north- 

 westerly heading to begin the pattern around the storm centre. The pattern 

 consisted of four legs forming a square around the centre, each leg being seventy 



18 



