6 comments

  • noway421 34 days ago

    Something happened just before the fuel pump battery hot-swap on the second stage. Here's some visualisation of the acceleration drop-off scraped from the web stream: https://twitter.com/DJSnM/status/1279583677890965504

    • SergeAx 33 days ago

      I am not a rocket scientist, but this looks like the hot swap never happened. Lower power on a pump, then it completely drained battery and just stopped, engine is off, end of story.

      It's a bit disappointing right because this hot-swap-and-then-ditch the battery maneuver is their key know-how, it helps to keep 2S engine simpler and cheaper.

      • rydre 33 days ago

        If the engines were shut down, the acceleration would be instantly negative. The decay happens faster, no shutdown until it hits zero.

        • SergeAx 33 days ago

          For negative acceleration the body needs a force applied in opposite direction. Atmosphere density @ 190 km is nine orders of magnitude less than at sea level, so the drag is negligible.

          • rydre 33 days ago

            Gravity is the negative acceleration force.

            • SergeAx 32 days ago

              Gravity vector was at the moment directed about 70-75 degrees relativе to speed. You may see the speed decreasing slightly while altitude still increasing, meaning vehicle gone ballistic.

        • mar77i 33 days ago

          Great Scott! Love his KSP content, where he discusses space trivia to no end...

        • cameldrv 34 days ago

          Can someone comment on the economics of this? Rocket Lab is charging $5m for 150kg to SSO. SpaceX offers 150kg to SSO on the smallsat rideshare for $1m. What sorts of payloads would not be suitable for rideshare or would be worth 5x the cost for better scheduling or a better orbit?

          • manquer 34 days ago

            It is never simple cost per kg calculation .

            Ridshare orbit depends on the primary orbit requirements, if the orbit is not favourable to your sat, correcting the orbit may not be feasible at all, given the small payload size you may not have the fuel for the correction burn

            Also fitting your sat to a rideshare payload adapter could be lot more complex depending on the primary and other shares

            Similarly while spaceX is cheap, there are plenty of workloads where ULA is the only option, vertical assembly , certain fairing sized , some orbits etc .

            • gutino 34 days ago

              - Type of orbit you want, SpaceX rideshare is like a bus trip, it will not get you exactly to your homes door. Rocket lab in this case is like a taxi.

              - Timing, perhaps you want to deliver sooner.

              • swatkat 33 days ago

                There are a few companies such as Spaceflight[1] that partner with launch providers such as ISRO[2][3] to offer rideshare and dedicated launches at much cheaper prices.

                [1] https://spaceflight.com/pricing/

                [2] https://www.isro.gov.in/launchers

                [3] https://www.nsilindia.co.in/launch-services

                • tigershark 33 days ago

                  They are cheaper only for nano satellites. From your first link it costs 295k$ for 10kg to LEO. With spaceX you can send up to 200 kg to LEO for 1M$. It’s 20 times the payload for ~3 times the price.

              • bryanlarsen 34 days ago

                IIRC, this breaks a record that no other rocket has achieved. Prior to this mission, every single Rocket Lab flight with a paying customer has been a success. Many other rockets have had 11 successes in a row, but no other rocket has had their first 11 launches with payloads be a success.

                (Rocket Lab's first mission was also a failure, but it did not have a payload. That failure was with ground equipment, so this current failure is their first rocket failure).

                • Rebelgecko 34 days ago

                  I don't think that's quite right

                  The Minotaur is currently 11/11 (with a 12th launch planned later this year).

                  Space Shuttle had 24 consecutive launches before a failure

                  The standard Delta IV has also had 24 consecutive successes.

                  • ls612 34 days ago

                    The Saturn V launched 13 times with no launch failures as well.

                    • vosper 33 days ago

                      I'll preface this by saying I don't know much about space launches...

                      > Space Shuttle had 24 consecutive launches before a failure

                      The Space Shuttle system was not "a rocket", so possibly GP wasn't counting it?

                      > The standard Delta IV has also had 24 consecutive successes.

                      Were those consecutive successes from the first launch without a dummy payload?

                      • Rebelgecko 33 days ago

                        >The Space Shuttle system was not "a rocket", so possibly GP wasn't counting it?

                        I don't see why the space shuttle wouldn't be considered a rocket? It had 3 rocket engines coming out the back of it.

                        >Were those consecutive successes from the first launch without a dummy payload?

                        Yes, although I goofed the math and it was actually 29. If we're excluding launches with dummy payloads, you could actually add in the Delta IV Heavy, which brings the total up to 39.

                        • vosper 31 days ago

                          > I don't see why the space shuttle wouldn't be considered a rocket? It had 3 rocket engines coming out the back of it.

                          Duh, you're right, of course - I somehow was thinking just of the boosters.

                        • conistonwater 33 days ago

                          Launches with payload numbers 5 through 40: https://en.wikipedia.org/wiki/Delta_IV#Delta_IV_launches_in_... I wonder if the trick is something like "launches in the same configuration" because that would really penalize older rockets that used to undergo upgrades once in a while.

                          • Rebelgecko 33 days ago

                            I don't know if there's an official definition, but I'd consider the Delta IV and Delta IV Heavy to be separate launch vehicles in the same family, akin to the Falcon 9 and Falcon Heavy. Whereas with the single-stick Delta IV Medium, the variations like 4m vs 5m fairings are just different configurations.

                    • SergeAx 34 days ago
                      • numpad0 34 days ago

                        Is it just me or does S2 appears rolling to the right in camera?

                      • p1mrx 34 days ago

                        At least we know Rocket Lab's webcast uses real telemetry, unlike Blue Origin, where they break the laws of Physics by pausing at 0 MPH: https://youtu.be/sUEj4dxPMbI?t=2658

                        • google234123 34 days ago

                          I like how a 1 second pause in telemetry makes you so certain that Blue Origin is fraudulent. Anyway, what is the point of your comment on this thread anyway?

                          • p1mrx 34 days ago

                            I don't think Blue Origin as a whole is fraudulent, just that they're not showing real telemetry data. By way of comparison, I think it's commendable that Rocket Lab's stream was accurate enough for viewers to see the failure occurring live.

                            • reitzensteinm 33 days ago

                              It shows that they're not showing unfiltered telemetry data, but it absolutely does not prove it's not real at all. Interpolation, rounding, sampling frequency in combination would easily explain this.

                              Not to mention that the speed freezes quite frequently at other points in the video...

                              • google234123 33 days ago

                                Faking the data seems like more work than just showing the data they are getting from the rocket which is why I'm personally skeptical.

                                • p1mrx 33 days ago

                                  Re-watching the numbers during the Blue Origin launch, it would've been tedious to fake the jumpiness using a pre-rendered animation, so perhaps the number fudging is limited to a "pause at zero" hack. Still, the presence of a "marketing telemetry" algorithm makes it seem less trustworthy for determining whether a failure occurred.

                            • SergeAx 33 days ago

                              Yes, I was impressed by Rocket Lab telemetry too. The picture is freezing and I can see by numbers that vehicle gone ballistic...

                              • danbr 34 days ago

                                New Shepard is a suborbital rocket. It reaches apogee (velocity drops to zero), and drops back to land propulsively.

                                It’s possible it experiences zero-G for more than just a few milliseconds at its apogee. Hence the 0mph velocity.

                                • p1mrx 34 days ago

                                  You fell victim to one of the classic blunders: conflating velocity with its derivative.

                                  The (approximately) zero-G period lasts for minutes, not milliseconds, and during that time, the velocity changes by 9.8 m/s (22 MPH) every second. The velocity should not pause at 0, or any other value.

                                  • dmurray 33 days ago

                                    22 mph per second is an abomination of a mixed unit I'd never heard before, but it's actually much more intuitive to me than the standard 9.8 metres per second per second.

                                    Maybe we can compromise on 35 km/h per second though.

                                    • p1mrx 31 days ago

                                      I wouldn't normally use MPH/s, but it fits the units in the Blue Origin video.

                                  • mlindner 33 days ago

                                    New Shepard is not traveling perfectly vertical, there's always a horizontal component so the velocity will never be zero. Even if you fly up in a perfectly vertical line, you'll gain horizontal velocity as you climb as the Earth's surface moves away from you from it's rotation.

                                • st_goliath 33 days ago

                                  Obligatory analysis video by Scott Manley:

                                  https://www.youtube.com/watch?v=ayYgPdk0VVc