issued at H minus 2h and H rinus 8 hours. Theseecnsistoé of trajottepice
fromthe shet site for the period H to M plus 72 hears, and were fop such
ten thousand feet, from ten te sinty theusané feet,
Revised trajectories
for the same period were issued af E plue 6 and H plus 15 hours,
fince
the trajectories represented movement ef air at specie senstant eltitudes,
they were act directly useable fer surface fall-eet forecasting.
Instead,
the forecasts were used by Radsafe perecenel primarily te sesist in analysis
of the long-range fall-out aspects and te alert other units ef the Amed
Forcea relative te the probable locations and altitudes of areas of airborne
radioactive particles.
The trajectories were prepared by censtructing
proqnostie charts for the period ef tine inwived and using these charte te
arrive at the trajectorice,
The aumber cf prognostic charte varied ith
the simplicity of the eystene, fower being wed vith systems moving o
developing alody, and moe for eyutene developing rapidly.
The trajectories
were derived mechanically by the superposition af ene prognostiechart over
encther ant making « sacoth transition from the flew and speedfield of one
chart to the Other,
oom
4. ConstantAltitude Bellow Flights, During the planing phase
of CASTLE, it was proposed that « project be instituted hereby constant
altitude balloons wuldbeused to determine thefeasibility of tracing
radicsstive debrisat selected levels.
This use of these ballconsas
predicated ca the assumption thet the movement of that part of the ratio
active cloud debris remaining in the air at a particular level eould be
deseribed ty a balloon flow at the same level, the balloon and radicactive
debris being similtanecusly carried along.
Since these balloons could be