Quote from: DavP on 06/15/2021 07:05 amAlso some of the engines are marked in green and others in white.The green engines are gimballed while the white are fixed.
Also some of the engines are marked in green and others in white.
This has been posted in another threadIt shows what appears to be a countdown to the orbital test launch and the engine configuration of the rockets.Also some of the engines are marked in green and others in white.
I think green are engines shipped. You'll notice one of the inner three starship engines is white.
All of this could be understand with a bit of time in Kerbal Space Program, even in the tuturials, but the real answer is whether starship will need to do a deorbit burn? If so, it was orbital, if it was going to decay on the first trip around the earth without a deorbit burn, it's not orbital.
Quote from: erictant on 06/09/2021 11:20 amQuote from: meekGee on 06/08/2021 03:53 pmQuote from: capoman on 06/08/2021 12:13 pmAll of this could be understand with a bit of time in Kerbal Space Program, even in the tuturials, but the real answer is whether starship will need to do a deorbit burn? If so, it was orbital, if it was going to decay on the first trip around the earth without a deorbit burn, it's not orbital.Not sure about that..Since there's no such thing as a gravitational decay in a two body classical system, then you're talking about aerodynamic decay, and then no, decay during the first orbit doesn't mean you weren't orbital, not any more than if you actively de-orbited.I think we are really discussing the difference between the behaviour of Spherical Cows orbiting Billiard Balls and Real Rockets orbiting Planets.QuoteThe best definition is whether at insertion you had enough energy to ballistically go around the earth.For the Cow, this will mean you stay in orbit forever. For the Rocket, you will immediately experience aerodynamic drag and effectively begin your deorbit manoeuvre. You are now in a region where you must balance drag and boost if you wish to maintain orbital velocity.If you want to stay in orbit around your Planet you have to go higher to reduce the drag to a manageable level. The ISS is near the top of this region and is effectively deorbiting all the time and left to its own devices would re-enter. It is only kept there by regular orbit boosting burns.SpaceX are deliberately exploiting the bottom edge of this region to allow for a controlled and predictable flight profile that does not require additional burns and all the complexities that entails. This allows them to maximise the chance of getting permits and also of being able to test high speed re-entry with a passive deorbit system.So, yes, Starship will be orbital momentarily (English meaning) but will immediately start to deorbit so will not go all the way around.I don't think they're trying to naturally decay within one-half of an orbit - I think they specifically said they'll do a de-orbit burn.They want to a) demonstrate orbital velocity and b) hit a specific landing zone.Besides, natural decay within one-half of an orbit is really difficult and serves no useful purpose.
Quote from: meekGee on 06/08/2021 03:53 pmQuote from: capoman on 06/08/2021 12:13 pmAll of this could be understand with a bit of time in Kerbal Space Program, even in the tuturials, but the real answer is whether starship will need to do a deorbit burn? If so, it was orbital, if it was going to decay on the first trip around the earth without a deorbit burn, it's not orbital.Not sure about that..Since there's no such thing as a gravitational decay in a two body classical system, then you're talking about aerodynamic decay, and then no, decay during the first orbit doesn't mean you weren't orbital, not any more than if you actively de-orbited.I think we are really discussing the difference between the behaviour of Spherical Cows orbiting Billiard Balls and Real Rockets orbiting Planets.QuoteThe best definition is whether at insertion you had enough energy to ballistically go around the earth.For the Cow, this will mean you stay in orbit forever. For the Rocket, you will immediately experience aerodynamic drag and effectively begin your deorbit manoeuvre. You are now in a region where you must balance drag and boost if you wish to maintain orbital velocity.If you want to stay in orbit around your Planet you have to go higher to reduce the drag to a manageable level. The ISS is near the top of this region and is effectively deorbiting all the time and left to its own devices would re-enter. It is only kept there by regular orbit boosting burns.SpaceX are deliberately exploiting the bottom edge of this region to allow for a controlled and predictable flight profile that does not require additional burns and all the complexities that entails. This allows them to maximise the chance of getting permits and also of being able to test high speed re-entry with a passive deorbit system.So, yes, Starship will be orbital momentarily (English meaning) but will immediately start to deorbit so will not go all the way around.
Quote from: capoman on 06/08/2021 12:13 pmAll of this could be understand with a bit of time in Kerbal Space Program, even in the tuturials, but the real answer is whether starship will need to do a deorbit burn? If so, it was orbital, if it was going to decay on the first trip around the earth without a deorbit burn, it's not orbital.Not sure about that..Since there's no such thing as a gravitational decay in a two body classical system, then you're talking about aerodynamic decay, and then no, decay during the first orbit doesn't mean you weren't orbital, not any more than if you actively de-orbited.
The best definition is whether at insertion you had enough energy to ballistically go around the earth.
Quote from: Durham Park on 06/15/2021 10:05 amI think green are engines shipped. You'll notice one of the inner three starship engines is white.Yes. Engines shipped. That appears on the screen.That countdown could be the deadline to have all the needed engines shipped
Quote from: DavP on 06/15/2021 11:02 amQuote from: Durham Park on 06/15/2021 10:05 amI think green are engines shipped. You'll notice one of the inner three starship engines is white.Yes. Engines shipped. That appears on the screen.That countdown could be the deadline to have all the needed engines shippedI wonder if "shipped" means the engines left Hawthorne for testing in McGregor, or whether it means they've completed testing and certification at McGregor and have been shipped to Boca Chica...
Quote from: DBMandrake on 06/17/2021 09:04 amQuote from: DavP on 06/15/2021 11:02 amQuote from: Durham Park on 06/15/2021 10:05 amI think green are engines shipped. You'll notice one of the inner three starship engines is white.Yes. Engines shipped. That appears on the screen.That countdown could be the deadline to have all the needed engines shippedI wonder if "shipped" means the engines left Hawthorne for testing in McGregor, or whether it means they've completed testing and certification at McGregor and have been shipped to Boca Chica...Throughout my career, every manufacturing facility that I've known considered"leaving our loading dock" as "shipped".I've seen instances of the cargo part of a 6 wheeler loaded and pushed into theparking lot to await it's front part and that was considered shipped!So I would expect shipped meant left Hawthorne loading dock.Carl
Quote from: DBMandrake on 06/17/2021 09:04 amQuote from: DavP on 06/15/2021 11:02 amQuote from: Durham Park on 06/15/2021 10:05 amI think green are engines shipped. You'll notice one of the inner three starship engines is white.Yes. Engines shipped. That appears on the screen.That countdown could be the deadline to have all the needed engines shippedI wonder if "shipped" means the engines left Hawthorne for testing in McGregor, or whether it means they've completed testing and certification at McGregor and have been shipped to Boca Chica...Just spitballing here, but I would guess "shipped" means "shipped" - i.e., finished manufacturing and left the factory. This display is in Hawthorne, after all.
Yes the expected production rate (shipped out the door from Hawthorn) as evidence from the poster is 24 engines in just less than 26 days!!!!The real question are they hitting that expected or is it closer to the 1 engine every 2 days from a Elon tweet.So if that video dates back to end of April first week of May. A much slower production rate of 24 engines in 50 days would be end of June first week of July. Currently the tea leaves are all saying that the first set will all be at Boca Chica by mid July. So the status info and production rate expectation and actual all add up to that the engines will be ready for install on flight vehicles in mid /late July.Now still need the GSE and the FAA launch license + FCC approvals for the mission/flight experiment.
Now still need the GSE and the FAA launch license + FCC approvals for the mission/flight experiment.
I suspect everything will be ready long before the FAA approves of the orbital flight. This might cause a window to allow another flight of Starship which will likely be easier to get approval for.
Also, I believe some SH testing should be possible with the current license too. Maybe not a 29 engine static fire, but possibly cryo or smaller cluster static fires, hot gas thruster tests, etc. So they could still proceed getting SH ready and taking the tank farm online. As long as they have their launch mount and GSE ready, they can continue working towards the orbital launch, while possibly resuming Starship testing. And once they got their launch license, they can proceed with that ASAP.
Scott Manley @DJSnMStarship test flights have all used compressed nitrogen for reaction control thrusters, this looks likely to be the hit has version. Little rocket motors using pressure fed Methalox in gas form - pressurized gas makes them easier to turn in and off for accurate control.
Elon Musk @elonmuskCool, but an unnecessary complication for now. These are being removed to speed up time to orbital launch.
If we needed any more proof that SpaceX is running multiple development paths in parallel, QuoteScott Manley @DJSnMStarship test flights have all used compressed nitrogen for reaction control thrusters, this looks likely to be the hit has version. Little rocket motors using pressure fed Methalox in gas form - pressurized gas makes them easier to turn in and off for accurate controlhttps://twitter.com/DJSnM/status/1407754444884742152?s=20QuoteElon Musk @elonmuskCool, but an unnecessary complication for now. These are being removed to speed up time to orbital launch.https://twitter.com/elonmusk/status/1407969457411067905?s=20It's cool they're developing the hot gas thrusters, it's even more cool they aren't going to let that development get in the way of testing the rest of the booster.
Scott Manley @DJSnMStarship test flights have all used compressed nitrogen for reaction control thrusters, this looks likely to be the hit has version. Little rocket motors using pressure fed Methalox in gas form - pressurized gas makes them easier to turn in and off for accurate control
Quote from: dgkimpton on 06/24/2021 09:16 amIf we needed any more proof that SpaceX is running multiple development paths in parallel, QuoteScott Manley @DJSnMStarship test flights have all used compressed nitrogen for reaction control thrusters, this looks likely to be the hit has version. Little rocket motors using pressure fed Methalox in gas form - pressurized gas makes them easier to turn in and off for accurate controlhttps://twitter.com/DJSnM/status/1407754444884742152?s=20QuoteElon Musk @elonmuskCool, but an unnecessary complication for now. These are being removed to speed up time to orbital launch.https://twitter.com/elonmusk/status/1407969457411067905?s=20It's cool they're developing the hot gas thrusters, it's even more cool they aren't going to let that development get in the way of testing the rest of the booster.Proof?Whatever is being said is fairly garbled."...the hit has version"?What's a guess as to what Manley meant?And what, specifically is that "unnecessary complication"?RCS engines burning "methalox", which would actually be gaseous methane and oxygen?And what is that complex bit of plumbing photographed by Kenniston?
Proof?Whatever is being said is fairly garbled."...the hit has version"?What's a guess as to what Manley meant?And what, specifically is that "unnecessary complication"?RCS engines burning "methalox", which would actually be gaseous methane and oxygen?And what is that complex bit of plumbing photographed by Kenniston?