cubinator Posted November 12, 2021 Share Posted November 12, 2021 3 hours ago, JoeSchmuckatelli said: I'm no rocket scientist - but the space for the door of the new building looks narrower than the existing bay It's about the same size. Quote Link to comment Share on other sites More sharing options...
RCgothic Posted November 12, 2021 Share Posted November 12, 2021 6 Raptors is much more thrust than 4 RS25s, just saying. Quote Link to comment Share on other sites More sharing options...
JoeSchmuckatelli Posted November 12, 2021 Share Posted November 12, 2021 3 minutes ago, RCgothic said: 6 Raptors is much more thrust than 4 RS25s, just saying. In the 3x3 config? Quote Link to comment Share on other sites More sharing options...
Beccab Posted November 12, 2021 Share Posted November 12, 2021 6 minutes ago, JoeSchmuckatelli said: In the 3x3 config? Yup, a raptor and an RS-25 have a quite similar thrust I believe Quote Link to comment Share on other sites More sharing options...
JoeSchmuckatelli Posted November 12, 2021 Share Posted November 12, 2021 27 minutes ago, Beccab said: Yup, a raptor and an RS-25 have a quite similar thrust I believe Here's something I don't fully understand - if they have vac thrusters and ASL thrusters, do they fire all 6 after separation from the booster, or just the vac thrusters and save the ASL for landing? Quote Link to comment Share on other sites More sharing options...
RCgothic Posted November 12, 2021 Share Posted November 12, 2021 14 minutes ago, JoeSchmuckatelli said: Here's something I don't fully understand - if they have vac thrusters and ASL thrusters, do they fire all 6 after separation from the booster, or just the vac thrusters and save the ASL for landing? Yes, all 6 at stage sep. It's necessary for the TWR, though they may throttle some SL engines off as TWR improves to improve ISP. Quote Link to comment Share on other sites More sharing options...
Beccab Posted November 12, 2021 Share Posted November 12, 2021 20 minutes ago, JoeSchmuckatelli said: Here's something I don't fully understand - if they have vac thrusters and ASL thrusters, do they fire all 6 after separation from the booster, or just the vac thrusters and save the ASL for landing? All of them, while at that altitude and speed TWR > 1 is not needed firing 6 at the same time reduce gravity losses enough that it compensates the lower general isp Quote Link to comment Share on other sites More sharing options...
cubinator Posted November 12, 2021 Share Posted November 12, 2021 (edited) 1 hour ago, RCgothic said: 6 Raptors is much more thrust than 4 RS25s, just saying. So what you're telling me is that the contracted lunar lander is more powerful than the crew launch vehicle Well, maybe not. Edited November 12, 2021 by cubinator Quote Link to comment Share on other sites More sharing options...
GuessingEveryDay Posted November 12, 2021 Share Posted November 12, 2021 Would it be possible for them to only add the RVacs for Lunar SS, and whatever landing engines they need? They don't need the sea-level Raptors, just the RVacs, right? Quote Link to comment Share on other sites More sharing options...
RealKerbal3x Posted November 12, 2021 Share Posted November 12, 2021 6 minutes ago, GuessingEveryDay said: Would it be possible for them to only add the RVacs for Lunar SS, and whatever landing engines they need? They don't need the sea-level Raptors, just the RVacs, right? The RVacs don't have gimbal, so removing the sea-level engines would make steering the vehicle difficult, especially during ascent from Earth. The sea-level engines are also useful for countering gravity losses during ascent, though they may be able to get by on RVacs alone (ignoring the complications of steering I mentioned above). Quote Link to comment Share on other sites More sharing options...
GuessingEveryDay Posted November 12, 2021 Share Posted November 12, 2021 3 minutes ago, RealKerbal3x said: The RVacs don't have gimbal, so removing the sea-level engines would make steering the vehicle difficult, especially during ascent from Earth. Upgraded RCS. Quote Link to comment Share on other sites More sharing options...
Meecrob Posted November 13, 2021 Share Posted November 13, 2021 RCS is probably at least an order of magnitude of force below gimballing. There is a reason aircraft have control surfaces, not little engines to adjust trajectory. Quote Link to comment Share on other sites More sharing options...
JoeSchmuckatelli Posted November 13, 2021 Share Posted November 13, 2021 2 hours ago, Meecrob said: RCS is probably at least an order of magnitude of force below gimballing. There is a reason aircraft have control surfaces, not little engines to adjust trajectory. RCS is for docking / minor adjustments, right? For SS to gimbal, don't the big guns have to be firing? (I write this, but then I also remember seeing Falcon RCS active during the landing - so maybe it's necessary fine control that works hand in hand with gimbal?) Quote Link to comment Share on other sites More sharing options...
RCgothic Posted November 13, 2021 Share Posted November 13, 2021 5 hours ago, JoeSchmuckatelli said: RCS is for docking / minor adjustments, right? For SS to gimbal, don't the big guns have to be firing? (I write this, but then I also remember seeing Falcon RCS active during the landing - so maybe it's necessary fine control that works hand in hand with gimbal?) Yes, gimballing only works when the main engines are on. RCS is for control at speeds where aero surfaces are ineffective (e.g. slow on landing) or where there's no atmosphere at all. They're also used to "quench" the gyroscopes when they get close to their limits. Quote Link to comment Share on other sites More sharing options...
RealKerbal3x Posted November 13, 2021 Share Posted November 13, 2021 About 3 mins to launch Quote Link to comment Share on other sites More sharing options...
Beccab Posted November 13, 2021 Share Posted November 13, 2021 Lots of fog Quote Link to comment Share on other sites More sharing options...
RealKerbal3x Posted November 13, 2021 Share Posted November 13, 2021 Liftoff! Max Q Stage sep Stage 1 has landed Quote Link to comment Share on other sites More sharing options...
RealKerbal3x Posted November 13, 2021 Share Posted November 13, 2021 Starlink deploy, extremely norminal mission today! Quote Link to comment Share on other sites More sharing options...
tater Posted November 13, 2021 Share Posted November 13, 2021 Quote Link to comment Share on other sites More sharing options...
Spaceman.Spiff Posted November 13, 2021 Share Posted November 13, 2021 18 hours ago, RealKerbal3x said: The RVacs don't have gimbal, so removing the sea-level engines would make steering the vehicle difficult, especially during ascent from Earth. The sea-level engines are also useful for countering gravity losses during ascent, though they may be able to get by on RVacs alone (ignoring the complications of steering I mentioned above). Well with the additional space afforded by not having SLRaptors, a gimbal mechanism could probably be added. (If it’s something that RCS can’t deal with) Quote Link to comment Share on other sites More sharing options...
tater Posted November 13, 2021 Share Posted November 13, 2021 Quote Link to comment Share on other sites More sharing options...
RealKerbal3x Posted November 13, 2021 Share Posted November 13, 2021 1 minute ago, Spaceman.Spiff said: Well with the additional space afforded by not having SLRaptors, a gimbal mechanism could probably be added. (If it’s something that RCS can’t deal with) There's definitely room for gimbal systems around the RVacs, but the problem is that the engine bells are tucked up right next to the skirt with no room to move. You could move the engines closer to the centre, but it sounds like a lot of work compared to just leaving the engine configuration as it is and benefiting from the extra thrust and control authority the sea-level engines provide. Quote Link to comment Share on other sites More sharing options...
Beccab Posted November 13, 2021 Share Posted November 13, 2021 I haven't seen anyone mention this yet - today was the 100th consecutive succesful falcon 9 mission! (as well as the 75th of falcon 9 block 5, all of which were successful) Quote Link to comment Share on other sites More sharing options...
tater Posted November 13, 2021 Share Posted November 13, 2021 Quote Link to comment Share on other sites More sharing options...
RCgothic Posted November 13, 2021 Share Posted November 13, 2021 1 hour ago, RealKerbal3x said: There's definitely room for gimbal systems around the RVacs, but the problem is that the engine bells are tucked up right next to the skirt with no room to move. You could move the engines closer to the centre, but it sounds like a lot of work compared to just leaving the engine configuration as it is and benefiting from the extra thrust and control authority the sea-level engines provide. They'd also have to shorten the bell or lengthen the skirt if the engines were moved inboard as they're mounted on the bottom of the tank dome. Quote Link to comment Share on other sites More sharing options...
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