RELEASE AND RECORDER RECORD B4-5 
is reached, the second observer will release the balloon, and the instant 
the train slackens, the first observer will run downwind until the balloon 
takes up the slack. As this happens, he will raise the radiosonde with his 
left hand and bring the cord forward withhis right hand. If the movement 
of his hands are coordinated, the radiosonde willfollow the balloon with 
no noticeable jerk. 
When obstructions prevent the observer with the radiosonde from run- 
ning downwind, the observer holding the radiosonde will stand in a posi- 
tion from which he can observe the movement of the balloon. At the in- 
stant the balloon takes up the slack, he will follow through with the radio- 
sonde to reduce the jolt and any possible damage to the radiosonde. 
In cases of very highand gusty surface winds, or where the balloon must 
be carried througha space without sufficient clearance, the balloon cover 
or shroud can be used. It should be placed on the balloon in accordance 
with instructions in §B3-10.1. To take the balloon from the inflation 
shelter, grasp two adjacent segments of the shroud in each hand. The 
two held in each hand should both be on the same side of the cord of the 
radiosonde train. In case of very high wind the loops on the top of the 
cover may be used by another observer to assist in guiding the balloon 
out of the shelter and tothe point of release. The hands should be placed 
so that one is slightly above the other, with the cord in the upper opening 
between the segments of the cover. To release, let go of the segments 
held by the upper hand so that the cover falls away from the cord. Pull 
slightly on the cover with the lower hand. The cover will drop away, with- 
out fouling the cord of the radiosonde train. The balloon will rise over 
the cover and gain altitude before picking up the weight of the radiosonde. 
It is sometimes possible to guide the radiosonde train around a trouble- 
some obstruction by means of an auxiliary cord attached to the neck of 
the balloon. With a train 70 to 100 feet long, the auxiliary cord should 
be about 60 feet long and should be attached to the doubled over portion 
of the balloon's neck to avoid damaging the film. At release, one ob- 
server would carry the radiosonde downwind from the balloon and slight- 
ly to one side of the obstruction. A second observer would carry the 
auxiliary cord downwind from the balloon and further to the same side 
of the obstruction so that auxiliary cord is taut and forms an angle of 
about 45° with the line from the balloon to the radiosonde. A third ob- 
server should hold the balloon. At the moment of release, force applied 
to the auxiliary cord willdeflect the balloonand cause it to travel across 
the wind flow as well as downwind as it rises. When the lateral move- 
ment has been sufficient for the train to clear the obstruction, the aux- 
iliary cord should be released to permitthe train to continue its ascent. 
sis (6g FMH#3 
