@BonhommeJerome @KSpaceAcademy Starliner is N22. No fairing, 2 solids, 2 RL10s. To launch crew, no fairing for safety/abort
Any update on when ULA will fly the first dual engine Centaur on Atlas V?
Right, I got the picture. However, according to ULA the first digit refers to the fairing diameter, not if the Centaur is encapsulated or not (which is a natural byproduct of the fairing variant used of course). So if they use no fairing at all it's kind of misleading to designate the variant 422 imho.
5XX means fairing that encapsulates the whole centaur, 4XX means fairing on top centaur, exposing Centaur.In the Starliner configurtion, the Centaur is not inside a failring, so 4XX.
Quote from: hkultala on 05/29/2017 01:43 pm5XX means fairing that encapsulates the whole centaur, 4XX means fairing on top centaur, exposing Centaur.In the Starliner configurtion, the Centaur is not inside a failring, so 4XX.Nope. There used to be an Atlas V 300 configuration as well (would've been used both for narrow payloads on Atlas V-Centaur, and all payloads for Atlas V Lite (Atlas V-Agena 2000). 400/500 just means the fairing diameter
There definitely WAS an Atlas V 300. Specific reference to it exists in several regulatory and development documents. It wasn't abandoned until sometime after 2000, the last document I can find that mentions it is https://www.faa.gov/about/office_org/headquarters_offices/ast/licenses_permits/media/eelvSEis.pdf and thats after the Atlas V name was finalized. As best as I can tell, CUS was still planned to use RL10E-1 up until very shortly before the name change to Atlas V as well.
That's interesting, because when Lockheed ceded the small payload market to Delta II (mostly NASA missions segment) the plan was to just use the 401 for the GPS, DMSP, and DSCS, and other MLV-II class payloads.
Now I'm wondering if Lockheed ever used the 300 naming convention, or just the government.
Tory Bruno Verified account @torybruno 26m26 minutes agoVery exciting! Mighty #Atlas Booster for OFT, the first #Starliner test flight, (uncrewed). @BoeingDefense #LaunchAmerica #Boeing
I asked this in the ULA thread, but perhaps it is more applicable here. Are there flight requirements for the DEC before they will put people on the rocket? And do we know when the DEC will first fly?These requirements and difference across manufacturers are interesting. SpaceX is allowed their single 10x more powerful upper stage engine, but they seem to be required to do more testing of the final configuration than ULA despite ULA adding a whole engine to the design. Any input into the reasoning behind these requirements would be appreciated.
Quote from: intrepidpursuit on 05/10/2018 11:57 pmI asked this in the ULA thread, but perhaps it is more applicable here. Are there flight requirements for the DEC before they will put people on the rocket? And do we know when the DEC will first fly?These requirements and difference across manufacturers are interesting. SpaceX is allowed their single 10x more powerful upper stage engine, but they seem to be required to do more testing of the final configuration than ULA despite ULA adding a whole engine to the design. Any input into the reasoning behind these requirements would be appreciated.The DEC doesn't use two engines for safety - Two engines are needed for the required thrust. CST-100's will be heavy payloads for Atlas V, and they will also fly a different trajectory that requires more thrust.
EDS has been present on all Atlas launches for a while now.
Quote from: brickmack on 05/13/2018 10:11 pmEDS has been present on all Atlas launches for a while now.Incorrect. I suspect you may be confusing this with the Fault Termination System (FTS) that destructs the stack if a problem. EDS is not complete and will fly on OFT for the first time, but disabled.