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It's a two-stage launcher. The new Vulcan is the first stage, and a version of the venerable Centaur is the second stage. Unless I am mistaken, Bezos's big methane-oxygen engines are what power Vulcan. Centaur is hydrogen-oxygen.
I may be wrong, but originally, they were going to try to recover the engines only, not the whole Vulcan stage, to address reusability. Otherwise, this is just another expendable launcher.
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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You're right. Vulcan uses a pair of BE-4 engines. Engine pod will return via parachutes. And zero to six solid rockets, in pairs: GEM 63XL.
Upper stage will initially be Centaur III, or Centaur V, or ACES. Centaur III has a single RL-10 engine, Centaur V has two. Info-graphic says: "ACES is ULA's next generation upper stage. With integrated vehicle fluids, ACES can stay in orbit for weeks, not hours. In the future, ACES will possess on-orbit refuelling capabilities. This will on-orbit ACES stages to be reused, dramatically reducing cost and enabling the launch of much heavier spacecraft to the distant reaches of our solar system." The info-graphic shows same diameter as Vulcan core stage, and 4 RL-10 engines.
Hmm. Why does their flight profile not mention the engine pod separating and returning? Have they abandoned reuse?
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Rob:
Makes me also wonder whether they have abandoned re-use. Of course, perhaps they just don't want to attempt that nuance on the first flight or flights. Adding that complication later does make a lot of sense.
GW
GW Johnson
McGregor, Texas
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Lockheed-Boeing Alliance Hit With US Fine for Launch Delays over delays of two military satellite launches this year, according to the service.
This should apply to all of the other collaborations...
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I see in the AIAA's email newsletter "Daily Launch" that Northrup-Grumman's "Cygnus" cargo craft is no longer launching to the ISS via ULA, now instead riding a Falcon-9 from SpaceX. It used to ride up on ULA's Atlas-5 launcher, which is now essentially gone except for a last few military missions.
I also see that Falcon-9 successfully put the Cygnus onto a transfer trajectory to the ISS, which I think is an ellipse with apogee near the ISS orbit, and perigee just out of the atmosphere. That would be a slightly shorter period, allowing the cargo craft to "wait out" the synchronization of ISS being there when Cygnus reaches its apogee. You circularize, and it's close-in maneuvering from there to docking.
I also see in the newsletter today that the circularization burn failed to work right, because the thruster shut down too early. Shades of Boeing and its Starliner thruster problems! Although, I'm not aware of this having been a problem on earlier Cygnus flights.
GW
GW Johnson
McGregor, Texas
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I saw today a story on CBS News indicating the Cygnus (the longer, heavier XL model) has reached the ISS. It turned out to be a software fault that shut the engine down prematurely during its burns. The engine itself was healthy. This was the one I reported about in the previous posting, launched by a Falcon-9.
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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from the AIAA email newsletter "Daily Launch" for Thurs 2-12-2026:
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Spaceflight Now
Vulcan suffers solid rocket booster problem during USSF-87 launch
ULA said an issue affected one of the four solid rocket boosters that helped propel its Vulcan rocket into space Thursday on a mission for the United States Space Force. Despite the problem the rocket, making only its fourth flight, continued on its planned trajectory, the company said. The rocket thundered away from pad 41 at Cape Canaveral Space Force Station at 4:22 a.m. EST but less than 30 seconds into the flight, there appeared to be a burn through of one of the nozzles on a Northrop Grumman-built graphite epoxy motor (GEM) 63XL solid rocket boosters (SRBs).
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My take: This is not the first such issue with this solid's nozzle. Somebody is not paying enough attention to the highly-erosive ablative insulation environment approaching and through the throat of a solid rocket nozzle. Whether out of ignorance or being too cheap is not knowable from this. If you complicate the design by adding thrust vector capability, you raise the odds of such burn-through or nozzle-loss failures, I do know that!
Reinforced rubbers do not hold up in the high shear flow. It takes hard silica phenolic plus a graphite throat insert, and that does NOT deflect to vector the nozzle bell! You have to deflect to vector out near the full case diameter where the scrubbing fluid shear, to get the rubber to hold up. Even then, you must do that deflection while still holding the full compressive thrust load aligned where you want it. Vectoring a solid rocket is a bad thing to attempt.
GW
Last edited by GW Johnson (Yesterday 09:44:17)
GW Johnson
McGregor, Texas
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sounds like the same issues for the old ATK version where its justifying making them cheaper rather than robust.
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