FIRST STEPS TOWARD SPACE - Smithsonian Institution Libraries

180 SMITHSONIAN ANNALS OF FLIGHT
FIGURE 1.—Two-stage ramjet rocket being prepared on launching rack, showing first-stage solid
propellant rocket below fins.
ramjet rocket climbed with increasing velocity.
Those present at the tests could see distinctly that
the rocket flight was successful.
The observations made by the group of astronomers
established the following pattern of the rocket
flight:
The first stage having burned out, the rocket
acquired a velocity of 200 m/sec and reached a
height of 250 m. After the burnout, the first stage
was separated from the second one by its aerodynamic
brake. The interval between powder burnout
and ignition of the ramjet engine was about 2.5
sec. During this period the rocket traversed 375 m
and attained a height of 625 m, at which point the
rocket velocity had decreased to 105 m/sec. At this
velocity the ramjet cut in, and it burned for 5.12
sec. By the end of the engine burn, the rocket
reached 1317 m and acquired a velocity of 224
m/sec. After burnout of the ramjet, the rocket
coasted upward for 6.06 sec, climbing to a height of
1808 m. By the end of the engine burn, the value
of extra thrust, that is, the difference between thrust
and drag, was equal to 20 kg, the coefficient of
thrust being 0.7. During the entire rocket flight with
the ramjet cut in, the average acceleration was 23
m/sec 2 .
Test results of these world's first ramjet rocket
launches were set down in a statement worthy of
being quoted in full:
Statement on ramjet engine test:
On May 19, 1939, the ramjet engine constructed by I. A.
Merkulov was tested at an airfield near the Planernaya
Station (near Moscow).
The test object was a wingless torpedo with a ramjet
engine.
The fuel blend for this engine was prepared at the Mendeleyev
Chemical-Engineering Institute.
For boosting the torpedo a conventional powder rocket
was used.
Ignition of the fuel composition and the powder rocket
was performed with electric plugs fed from a battery. To
delay the ignition of the fuel for 1 sec after the powder
rocket ignition, a stopin fuse was placed between the fuel
and the electric plug. The torpedo flight height and velocity
were determined by the group of astronomers.