Visiteur non identifié - Connexion - Inscrivez-vous
Space Exploration Technologies Corp. (SpaceX) announced today that
it has completed development of its Merlin 1C next generation liquid
fueled rocket booster engine. It is among the highest performing gas
generator cycle kerosene engines ever built, exceeding the Boeing
Delta II main engine, the Lockheed Atlas II main engine, and on par
with the Saturn V F-1 engine.
The Merlin 1C is an improved version of the Merlin 1A ablatively
cooled engine, which lofted the Falcon 1 on its first flight in March
2006 and second flight in March 2007. The regeneratively cooled Merlin
1C uses rocket propellant grade kerosene (RP-1), a refined form of jet
fuel, to first cool the combustion chamber and nozzle before being
combined with the liquid oxygen to create thrust. This cooling allows
for higher performance without significantly increasing engine mass.
"We performed the final test in the development series, a 170
second long mission duty firing," said Tom Mueller, Vice President of
Propulsion for SpaceX, from their Texas Test Facility in McGregor,
Texas. "This series of runs has verified the final design features.
Total run time on this engine exceeded 3,000 seconds across 125 hot
fire tests."
"The SpaceX Texas test facility was critical to the rapid and
efficient development of Merlin," said Elon Musk, CEO and CTO of
SpaceX. "In August alone, we ran twenty-one major Merlin test firings,
nearly one per working day, a rate we could not equal anywhere else.
The success of Merlin is really due to the joint function of a great
propulsion and test team."
Merlin 1C in its Falcon 9 first stage configuration has a thrust
at sea level of 95,000 lbs, a vacuum thrust of over 108,000 pounds,
vacuum specific impulse of 304 seconds and sea level thrust to weight
ratio of 92. In generating this thrust, Merlin consumes 350 lbs/second
of propellant and the chamber and nozzle, cooled by 100 lbs/sec of
kerosene, are capable of absorbing 10 MW of heat energy. A planned
turbopump upgrade in 2009 will improve the thrust by over 20% and the
thrust to weight ratio by approximately 25%.
The Merlin 1C will power SpaceX's next Falcon 1 mission, scheduled
to lift off in early 2008 from the SpaceX launch complex in the
Central Pacific atoll of Kwajalein. SpaceX's far larger Falcon 9
rocket, now in development, will employ nine Merlin engines on its
first stage, and one on the second stage. The Falcon 9 will have over
a million pounds of thrust - four times the maximum thrust of a Boeing
747.
The Merlin engine is the first new American booster engine in ten
years and only the second in over a quarter century. The prior two
American engines were the RS-68 developed in the late nineties by
Pratt & Whitney's RocketDyne division, used in the Boeing Delta IV
launch vehicle, and the Space Shuttle Main Engine developed in the
late seventies, also by RocketDyne.
SpaceX is preparing to produce more rocket engines than the rest
of US production combined. In 2008, SpaceX targets the manufacture of
approximately 50 booster engines, a number that exceeds the output of
any country except Russia.
About SpaceX
SpaceX is developing a family of launch vehicles intended to
reduce the cost and increase the reliability of both manned and
unmanned space transportation ultimately by a factor of ten. With its
Falcon line of launch vehicles, powered by Merlin engines, SpaceX is
able to offer light, medium and heavy lift capabilities to deliver
spacecraft into any inclination and altitude, from low Earth orbit to
geosynchronous orbit to planetary missions.
As winner of the NASA Commercial Orbital Transportation Services
competition, SpaceX will conduct three flights of its Falcon 9 launch
vehicle and Dragon spacecraft for NASA. This will culminate in Dragon
berthing with the International Space Station and returning safely to
Earth. When the Shuttle retires in 2010, Falcon 9 / Dragon will have
the opportunity to replace the Shuttle in servicing the Space Station.
Sélectionnez votre lecteur de news préféré ci-dessous :
Ou bien intégrez le flux XML dans votre agrégateur RSS par défaut : 
