190 
previously attained by rockets or by 
other means, but it also was sufficiently 
large that it could carry a payload 
much greater than any research work- 
er had hoped for. 
The work on the upper atmosphere 
utilizing the German V-2’s in this 
country has been going on for a little 
more than 1 year. Even in so short 
a time it can be stated that the V-2 
has already made important contribu- 
tions to such fields as solar spectros- 
copy, cosmic rays, and the measure- 
ment of atmosphere pressures and 
temperatures (6, 7, 8, 9). To those 
of us in the field, it is somewhat 
surprising, but nevertheless gratifying 
that the early experiments have proved 
so successful. We had anticipated 
that the complexities involved in 
perfecting the necessary new tech- 
niques could easily have consumed the 
first year’s work. 
First, I would like to say a few words 
about the organization of a project as 
large as this. There is no one organi- 
zation that encompasses the entire 
project. ‘The V—2’s themselves are as- 
sembled, made ready to fire, and fired 
by the Army Ordnance Department 
with the aid of the General Electric Co. 
under a special contract for this pur- 
pose. Once the V-2 has been fired, it 
is of course very important to know 
where it is at all times in its trajectory, 
so that data taken can be correlated 
against altitude, range, etc. The bal- 
listics and the problem of tracking in 
general, involving many types of radio, 
radar, and optical methods, are the 
responsibility of the Ballistic Research 
Laboratories of the Aberdeen Proving 
Ground. 
The actual upper-atmosphere work 
is conducted by various institutions 
including the Air Matériel Command, 
the University of Michigan, Watson 
Laboratories, the Applied Physics Lab- 
oratory of the Johns Hopkins Univer- 
sity, the Signal Corps, and the Naval 
Research Laboratory. In addition, 
there are numerous other contributing 
agencies, including Princeton Univer- 
sity, the National Bureau of Standards, 
ANNUAL REPORT SMITHSONIAN INSTITUTION, 1948 
Harvard University, and the California 
Institute of Technology. All the work 
is coordinated through a V-2 Panel 
which consists of members from most 
of the above-named institutions and 
agencies. 
The V-2 
Just to refresh your memories I 
might point out a few of the charac- 
teristics of the V—2 (10). Plate 1, 
figure 1 shows the V—2 on its launching 
patform. It stands about 46 feet high, 
has a total weight of 28,000 pounds 
when fueled and 9,000 pounds empty. 
The total weight of payload carried is 
about 2,000 pounds. Its diameter is 
65 inches. Stabilization is accom- 
plished by a set of carbon vanes placed 
in the jet, aided by a set of air vanes 
in the fins. Fixed gyroscope stabili- 
zation is maintained in azimuth, and 
a gyroscope program control feeds a 
predetermined tilt program to the 
fins. When the rocket motor is started, 
the rocket begins to rise slowly as soon 
as the acceleration due to the thrust 
exceeds 1 g. Since a rocket motor of 
this type is a constant-thrust device 
and since the mass is constantly de- 
creasing owing to fuel consumption, 
the acceleration gradually increases 
until after about 60 seconds it reaches 
a value of 6 g. At this point the fuel is 
completely consumed, the missile is 
out of the denser atmosphere and it 
proceeds on a trajectory which is a 
function only of its position and veloc- 
ity at the time of fuel burn-out. Up 
until the time of burn-out it is, as pre- 
viously pointed out, completely sta- 
bilized. Thereafter, since it is out of 
the atmosphere and since no more jet 
power is available, no further stabili- 
zation is obtained. The result is that 
any accidental angular momentum 
imparted during the fuel burn-out 
period produces a roll, pitch, or yaw 
during the remainder of the free-space 
flight. Here we encounter the first 
objectionable feature of the V-2 
rocket as a research vehicle. We find 
that, in general, there is a very definite 
roll about the rocket’s longitudinal axis 
