B4-28 
(1) 
(2) 
(3) 
(4) 
RELEASE AND RECORDER RECORD 
On a blank WBAN-31B, relabel as many isobars as nec- 
essary at half their printed value, e.g., 400 becomes 200, 
300 becomes 150, etc., 
Plot the entire continuous temperature trace on this ex- 
panded scale of the auxiliary WBAN-31B, 
Evaluate the temperature and select the 100 mb temper- 
ature, : 
Discard the auxiliary WBAN-31B. 
If the continuous temperature trace extends through the 12.5- 
10 mb. stratum; 
(1) 
(2) 
(3) 
(4) 
On a blank WBAN-31C relabel as many isobars as neces- 
sary at half their printed value, e.g., 25 becomes 12.5, 
20 becomes 10, etc. 
Plot the entire continuous temperature trace on this ex- 
panded scale of the auxiliary WBAN-31C, 
Evaluate the temperature and select the 10 mb temper- 
ature, 
Discard the auxiliary WBAN-31C. 
7.12 Hypsometer Failure. When a hypsometer is out of fluid or other- 
wise fails, the pressure indicated by the hypsometer begins to differ 
from that indicated by the baroswitch trace by increasing amounts. If the 
provisions of JB4-13.1 are met, so that pressure derived from the hyp- 
someter traces are used for radiosonde evaluation, and subsequently a 
difference of 5 mb or more between the pressure values indicated by the 
hypsometer and the baroswitch develops, then: 
a. 
I= WSO) 
If the pressure-altitude data has already been computed from 
hypsometer data and recomputation of the data using the baro- 
switch pressure is not feasible (i.e., due to time limitations), 
the flight willbe terminated at the levelat which the difference 
becomes 5 mb. 
If it is possible to recompute the pressure-altitude data using 
baroswitch data only, then the baroswitch pressure should be 
used and the flight evaluated to balloon burst or (WB) 5 mb. 
FMH#3 
