V—2 ROCKETS—KRAUSE 
passes through. The system uses sub- 
miniature tubes, operates at a fre- 
quency of approximately 1,000 mc., 
and has a peak power output between 
1 and 2 kw. The entire record of a 
flight is recorded on the ground by 
several different methods, the most 
important of which is a string oscillo- 
graph. A picture of a typical record- 
ing is shown in figure 2. 
We have under development and 
should have in use within the next 
6 months a 30-channel telemetering 
system using a 300-cycle sampling 
rate (12). By means of a subcommu- 
tator we will be able to extend the 
number of channels to 450 using a 
sampling rate of approximately 1 per 
second. 
The recovery of data by telemetering 
is not completely satisfactory in all 
cases. For example, the telemetering 
of spectrographic data, although pos- 
sible, is not very satisfactory. Further- 
more, in all cases when the missile 
begins to gyrate severely, as it does 
occasionally, the telemetered data is 
not continuous because the antenna is 
at times completely shadowed by the 
missile. For these reasons other 
methods of data recovery are being 
studied. One of these methods is the 
use of drag mechanisms, including 
parachutes. 
The use of drag mechanisms for 
recovery is probably feasible, but 
considerable development work still 
needs to be done. ‘The present method 
of recovery involves breaking up the 
missile during its downward flight in 
such a way that each individual piece 
coming down has a high drag coeffi- 
cient and very poor stability, the result 
being that the piece in question will 
tumble or float down. It has been 
found by this method that equipment 
even after very high flights will arrive 
at the earth in fair condition, and 
occasionally will be found completely 
intact. Thus, for example, on our 
October 10 flight, the spectrograph 
which was installed in a tail fin was 
recovered in such a good condition 
that further calibration runs were 
193 
made on it in the laboratory without 
readjustment. ‘The induced break-up 
had torn the fin loose and it had 
apparently floated back to the earth. 
Eight pounds of TNT tied to the 
beams supporting the warhead are 
usually used to produce blow-off. 
The correct time of detonation is 
obtained by means of a timer mecha- 
nism and also by means of radio such 
that the TNT is detonated by the 
appropriate one of these two methods 
at an altitude of about 60 km. above 
the earth on the downward flight. 
A photograph of a V—2 after a 170- 
km. high flight is shown in plate 2, 
figure 1. By this means we have to 
date recovered 4 spectrographs (2 in 
usable condition), 3 photographic 
recorders, 4 still-picture cameras and 
10 motion-picture cameras, most of 
which went to an altitude of 170 km. 
In all cases the films were in excellent 
condition, even though in some cases 
no precautions were taken to protect 
them on impact. 
Our present program is concerned 
with four fields of high-altitude re- 
search, namely, cosmic rays; the 
ionosphere; pressure, temperature, and 
composition measurements; and astro- 
physics involving primarily the spec- 
trum of the sun. A typical lay-out 
of these various experiments in a 
V-2 is shown in the sketch, plate 2, 
figure 2. A more detailed view of 
the installations in the warhead and 
control chamber is shown in plate 3, 
figures 1 and 2, and plate 4, figure 1. 
Beginning at the extreme nose tip 
of the missile we have an installation 
for measuring ram pressures. Im- 
mediately behind this in the war- 
head is the cosmic-ray telescope with 
the necessary electronics below the 
telescope. The ionosphere transmit- 
ter is directly below the cosmic-ray 
electronics. Also in the warhead are a 
timer, remote-control switching panel, 
accelerometers, telemetering commu- 
tator, batteries, and miscellaneous 
equipment. In the control chamber 
immediately behind the warhead are 
the telemetering transmitter, several 
