Each of the four RS-25 engines currently housed at NASA’s Space Launch System base has made multiple trips into space, and each engine has an interesting story to tell. First flight in 1998, sending astronaut John Glenn into orbit. Soon, if all goes well, these seasoned boosters will propel NASA into the age of Artemis.
NASA’s Space Launch System is the most powerful rocket ever built, capable of carrying more than 57,320 pounds (26 metric tons) of cargo and crew to the moon. Future configurations could see the rocket lift as much as 99,208 pounds (45 metric tons). It’s an engineering marvel — at least we hope — and its maiden voyage is scheduled for this Saturday at 2:17pm ET.But as NASA makes a bold leap Age of Artemis As well as the ever-increasing complexity of missions to the lunar environment, it’s important to remember that the SLS is a new type of rocket made from a bunch of old parts.
The fully integrated heavy-lift rocket is the perfect combination of previous NASA launch systems, especially the U.S. Space Shuttle, which was retired in 2011. In fact, Components from 83 Space Shuttle missions The SLS and Orion crew capsules have been cobbled together. It used the space shuttle main engine, now known as the RS-25 engine, built by Aerojet Rocketdyne, while its two extended solid rocket boosters were also borrowed from the space shuttle. The engines that previously operated the space shuttle also entered the Orion.
as a congress Tell Back in 2010, NASA’s new rocket and crew module would use “Space Shuttle-derived components…using existing U.S. propulsion systems, including liquid-fuel motors, external fuel tanks or tank-related capabilities, and solid rocket motors.” Consideration At this point, and not wanting to waste quality flight-proven hardware, NASA stripped the retired space shuttle’s main engine and stowed it away for safekeeping. This is in line with the directive to take full advantage of legacy hardware when building SLS “to save cost and speed up schedule”, according to to the space agency.
There is no doubt that the RS-25 is both powerful and reliable. These engines were upgraded five times during the space shuttle program, during which they participated in 135 missions, fired in more than 3,000 starts, and maintained power for 1 million seconds during ground testing and flight operations. In total, NASA has built up an inventory of 16 RS-25D engines from the space shuttle program to support the first four SLS missions. Of those 16 engines, only two never went into space.
The Space Shuttle is equipped with three RS-25 engines, while the SLS has four. Fueled by liquid hydrogen and liquid oxygen, the four engines are arranged roughly squarely to ensure stability and evenly distributed forces during liftoff. Each RS-25 engine can produce 2 million pounds of thrust, which, combined with two five-stage solid rocket boosters, will provide 8.8 million pounds of thrust at launch.In the space shuttle era, the RS-25 operated at 104.5% rated thrust (491,000 lb vacuum thrust), but for the SLS these engines have been modified to operate at 109% rated thrust (512,000 lb vacuum thrust), USA National Aeronautics and Space Administration Say.
“For SLS, the engine will experience higher propellant inlet pressures and temperatures,” NASA said. “In addition, existing inventory is receiving new engine controllers with modern avionics, as well as new exhaust nozzle insulation for higher heating environments.”
The current SLS configuration is called Block 1 and it includes four very experienced RS-25 engines. For the first flight of the SLS, NASA will use the E2045, E2056, E2058 and E2060 engines. In total, the four engines were involved in 21 space shuttle flights over 30 years.
The first engine, the E2045, is the most experienced, having flown 12 space shuttle missions. It flew for the first time during the STS-89 mission in January 1998, and its last shuttle flight took place during the STS-135 mission in July 2011. Astronaut John Glenn experienced the power of the E2045 firsthand while flying as part of the STS-95 mission in 1998.
The second engine, the E2056, was a veteran of four space shuttle flights (including the STS-114 — Colombia disaster), while the third engine E2058 took part in six flights. The fourth engine, the E2060, was the least experienced of the batch, having flown three missions, including STS-135, the final space shuttle mission.
It was the third engine that engineers blamed during a launch scrub on Monday, Aug. 29, when it failed to reach the ultra-cold temperature needed for launch, but the team later blamed the problem on a sensor malfunction. As SLS chief engineer John Blevins told reporters yesterday, there was nothing wrong with the E2058, as engineers were able to confirm “good flow” of cooled propellant through the No. 3 engine.
For each of the 16 RS-25 engines left over from the space shuttle era, their next flight will be their last. The SLS is an expendable rocket whose core stage is expected to splash down in the Pacific Ocean (side boosters will crash into the Atlantic Ocean).Once NASA runs out of its RS-25D engine inventory, the space agency will switch to RS-25E engines Currently under construction Courtesy of Aerojet Rocketdyne. The new engine will cost about 30 percent less than the previous engine and provide 111 percent of the rated thrust (521,000 pounds of vacuum thrust).
NASA needs SLS for the upcoming Artemis mission to the moon. Heavy lift systems will play a key role in Artemis 2, in which the manned Orion capsule will venture to the moon and back in late 2024, and Artemis 3, the first manned lunar landing since the Apollo era. The Artemis mission is also designed to prepare NASA and its partners for the first human journey to Mars, in which SLS is expected to play a key role.
As exciting as it all sounds, the price tag may be too high. NASA has spent more than $50 billion in development costs for SLS and Orion since 2011, according to to the Planetary Society. But to run SLS, NASA’s inspector general estimates that each launch of the first four Artemis missions will cost NASA more than $4.1 billion — a price that inspector general Paul Martin describes as “unsustainable. “
Through its Artemis program, NASA is seeking a permanent and sustainable return to the moon. If that happens, however, NASA will need to rein in skyrocketing costs.