134
3 A Brief History of Space Flight
In December 1938, under von Kármán’s behest, Malina presented a report on “Jet
Propulsion” to the National Academy of Sciences Committee on Army Air Corps
Research in Washington, D.C., where he intentionally avoided the word “Rocket”
which still had a poor reputation in scientific circles at that time. The report impressed
the U.S. Army Air Corps’s commanding general, Henry A. Arnold. As a result,
Arnold gave Malina’s team $1000 to develop rockets for Jet-Assisted Takeoff (JATO)
in January 1939, and half of a year later, gave them an additional $10,000. Arnold
hoped that the JATO rockets, mounted on an airplane’s wings, might help a heavily
laden aircraft takeoff from the short runways at islands on the Pacific Ocean [7].
With the support of the project funding, the team made every effort to develop solid
and liquid propellant units for the JATO.
For developing the solid-propellant rocket motor, the problem that the solid propellants fuel during a short time needed to be solved. Starting from the thermodynamic
equations, Malina and others had proved theoretically that it is feasible to use rocket
motor to assist heavy aircraft takeoff, and Parsons was responsible for the specific
development of the motor. By examining the theoretical stability of burning a solid
fuel under pressure, Malina and von Kármán obtained a conclusion, now known
as the von Kármán–Malina theory of constant-thrust long-duration engines, which
showed that the process could be made stable if the pressure inside the chamber
remained constant. For developing the liquid-propellant rocket motor, the problems
on the combustion efficiency and stability of the propellants needed to be studied
intensively. In 1940, Malina received a Ph.D. degree in aeronautics by his dissertation
entitled “Characteristics of the Rocket Motor and Flight Analyses of the Sounding
Rocket”.
In August 1941, the team’s gunpowder-based propellant was performing well
enough to warrant flight tests on an actual aircraft. They developed a solid rocket
motor with 4.7-kg weight that could produce a thrust of 12.7 kgf within 12 s. At March
Field, in California, their JATO rockets cut the takeoff distance of an Ercope, a fightersized civilian aircraft, by half. The U.S. Navy officials watching the assisted takeoff
test were interested in the rocket motors, and required the development of the solid
rockets with a thrust of 90 kgf, a working time of more than 20 s and a long storage
time. Especially, the JATO rockets stored for more than a few days would explode
upon ignition. For the better part of a year, Parsons and Malina searched in vain
for a solution. Until June 1942, Parsons got an inspiration from a construction crew
mixing molten asphalt, which he could cast asphalt with an oxidizer like potassium
perchlorate to create a solid propellant. The combustible asphalt would act as both
fuel and binder. Parsons’s idea, now known as composite propellant technology, has
been widely applied in torpedo, deep-water bomb, missiles and launch vehicles. The
rocket motors filled with the composite propellants are able to produce a thrust of
1000 kgf and a working time of more than 30 s. Meanwhile, the team had successfully
developed the liquid rocket engine with a thrust of 454 kgf and a working time of
25 s. Two liquid rocket engines were mounted to the lower part of the A-20 Attacker
to carry out the flight firing test, and no explosion occurred in the 44 tests. In the
same year, Malina together with von Kármán, Parsons, Forman and their colleague
Martin Sommerfield founded Aero-jet General Corporation to massively produce
3 A Brief History of Space Flight
In December 1938, under von Kármán’s behest, Malina presented a report on “Jet
Propulsion” to the National Academy of Sciences Committee on Army Air Corps
Research in Washington, D.C., where he intentionally avoided the word “Rocket”
which still had a poor reputation in scientific circles at that time. The report impressed
the U.S. Army Air Corps’s commanding general, Henry A. Arnold. As a result,
Arnold gave Malina’s team $1000 to develop rockets for Jet-Assisted Takeoff (JATO)
in January 1939, and half of a year later, gave them an additional $10,000. Arnold
hoped that the JATO rockets, mounted on an airplane’s wings, might help a heavily
laden aircraft takeoff from the short runways at islands on the Pacific Ocean [7].
With the support of the project funding, the team made every effort to develop solid
and liquid propellant units for the JATO.
For developing the solid-propellant rocket motor, the problem that the solid propellants fuel during a short time needed to be solved. Starting from the thermodynamic
equations, Malina and others had proved theoretically that it is feasible to use rocket
motor to assist heavy aircraft takeoff, and Parsons was responsible for the specific
development of the motor. By examining the theoretical stability of burning a solid
fuel under pressure, Malina and von Kármán obtained a conclusion, now known
as the von Kármán–Malina theory of constant-thrust long-duration engines, which
showed that the process could be made stable if the pressure inside the chamber
remained constant. For developing the liquid-propellant rocket motor, the problems
on the combustion efficiency and stability of the propellants needed to be studied
intensively. In 1940, Malina received a Ph.D. degree in aeronautics by his dissertation
entitled “Characteristics of the Rocket Motor and Flight Analyses of the Sounding
Rocket”.
In August 1941, the team’s gunpowder-based propellant was performing well
enough to warrant flight tests on an actual aircraft. They developed a solid rocket
motor with 4.7-kg weight that could produce a thrust of 12.7 kgf within 12 s. At March
Field, in California, their JATO rockets cut the takeoff distance of an Ercope, a fightersized civilian aircraft, by half. The U.S. Navy officials watching the assisted takeoff
test were interested in the rocket motors, and required the development of the solid
rockets with a thrust of 90 kgf, a working time of more than 20 s and a long storage
time. Especially, the JATO rockets stored for more than a few days would explode
upon ignition. For the better part of a year, Parsons and Malina searched in vain
for a solution. Until June 1942, Parsons got an inspiration from a construction crew
mixing molten asphalt, which he could cast asphalt with an oxidizer like potassium
perchlorate to create a solid propellant. The combustible asphalt would act as both
fuel and binder. Parsons’s idea, now known as composite propellant technology, has
been widely applied in torpedo, deep-water bomb, missiles and launch vehicles. The
rocket motors filled with the composite propellants are able to produce a thrust of
1000 kgf and a working time of more than 30 s. Meanwhile, the team had successfully
developed the liquid rocket engine with a thrust of 454 kgf and a working time of
25 s. Two liquid rocket engines were mounted to the lower part of the A-20 Attacker
to carry out the flight firing test, and no explosion occurred in the 44 tests. In the
same year, Malina together with von Kármán, Parsons, Forman and their colleague
Martin Sommerfield founded Aero-jet General Corporation to massively produce