SpaceX has worked with Planet to devise a means of attaching the Planet satellites on top of its stack of 60 Starlink satellites.
Interesting that F9 Block 5 as it stands is fairing volume-constrained for Starlink 200-km LEO orbit missions rather than payload mass-constrained. They are fitting some rideshares on top of the full stack of 60.QuoteSpaceX has worked with Planet to devise a means of attaching the Planet satellites on top of its stack of 60 Starlink satellites.https://arstechnica.com/science/2020/06/planet-teams-with-spacex-to-expand-its-earth-observation-constellation/This sure is a very capable LEO hauler.
It'd be interesting if they tested heatshield tiles on the bottom of Falcon 9 or, maybe more importantly, the center core of Falcon Heavy block 5.
Interesting that F9 Block 5 as it stands is fairing volume-constrained for Starlink 200-km LEO orbit missions rather than payload mass-constrained. They are fitting some rideshares on top of the full stack of 60.QuoteSpaceX has worked with Planet to devise a means of attaching the Planet satellites on top of its stack of 60 Starlink satellites.https://arstechnica.com/science/2020/06/planet-teams-with-spacex-to-expand-its-earth-observation-constellation/
This sure is a very capable LEO hauler.
Quote from: RedLineTrain on 06/09/2020 03:22 pmInteresting that F9 Block 5 as it stands is fairing volume-constrained for Starlink 200-km LEO orbit missions rather than payload mass-constrained. They are fitting some rideshares on top of the full stack of 60.QuoteSpaceX has worked with Planet to devise a means of attaching the Planet satellites on top of its stack of 60 Starlink satellites.https://arstechnica.com/science/2020/06/planet-teams-with-spacex-to-expand-its-earth-observation-constellation/Skysats are only 110kg each (less than half the mass of a Starlink satellite) and the rideshares are taking three each flight. So it's not all that much extra mass, even if you include whatever adapter they have to come up with. On the other handQuoteThis sure is a very capable LEO hauler.Yes, it surely is.
Quote from: abaddon on 06/09/2020 09:36 pmQuote from: RedLineTrain on 06/09/2020 03:22 pmInteresting that F9 Block 5 as it stands is fairing volume-constrained for Starlink 200-km LEO orbit missions rather than payload mass-constrained. They are fitting some rideshares on top of the full stack of 60.QuoteSpaceX has worked with Planet to devise a means of attaching the Planet satellites on top of its stack of 60 Starlink satellites.https://arstechnica.com/science/2020/06/planet-teams-with-spacex-to-expand-its-earth-observation-constellation/Skysats are only 110kg each (less than half the mass of a Starlink satellite) and the rideshares are taking three each flight. So it's not all that much extra mass, even if you include whatever adapter they have to come up with. On the other handQuoteThis sure is a very capable LEO hauler.Yes, it surely is.I was under the (possibly incorrect) impression that the ESPA rings for rideshares go on the bottom, with the Starlink stack taking the top slot. Assuming this new info wasn't a bad question/bad answer resulting in incorrect information (journalist asks how will rideshares fit, gets a pic of open space in the top of the payload fairing, then assumes they go on top), then that means the rings go on top, and the ring top slot is open (which sorta jives with the original rideshare announcement, which mentioned the top slot)Does that mean the rings would need to be separately pre-jettisoned prior to the Starlink swing-and-toss move, or will the rings be functionally tension anchored to the top of the stack using the existing retention rods/straps, such that when they do the swing-and-toss, the rideshare rings get released in the same movement? That might get a little hairy depending on the center of mass of the rideshares/rings...
twitter.com/erdayastronaut/status/1295884242375892995QuoteNow that you’re at 6 flights, still think 10 is possible? What do you think will be the limiting factor that will end their service life span?https://twitter.com/elonmusk/status/1296158590646939649QuoteI don’t want be cavalier, but there isn’t an obvious limit. 100+ flights are possible. Some parts will need to be replaced or upgraded. Cleaning all 9 Merlin turbines is difficult. Raptor is way easier in this regard, despite being a far more complex engine.
Now that you’re at 6 flights, still think 10 is possible? What do you think will be the limiting factor that will end their service life span?
I don’t want be cavalier, but there isn’t an obvious limit. 100+ flights are possible. Some parts will need to be replaced or upgraded. Cleaning all 9 Merlin turbines is difficult. Raptor is way easier in this regard, despite being a far more complex engine.
Falcon 9 was designed for maximum reliability and is the first orbital class rocket capable of reflight → spacex.com/vehicles/falco…
Hi all,sorry for bringing up an old Thread, but i didnt want to make a new one just because of my question.Since 2019 i have the impression, that more or less all F9 Launches come up with a cleary visible angle of attack of F9 stack roughly in the last 30 to 40 sec prior to MECO. As an example ive chosen Starlink Launch L23 from 2021-04-07. The effect im talking about starts at T+ 01:40 and lasts (with increasing angle) until T+ 02:24, when the F9 stack returns to zero angle of attack just before MECO. Well at least it seems to be an angle of attack to my eyes ...Its not only this launch, its more or less all launches i watched since nearly 2 years. Onboard footage also often shows a slight deviation of the plume in the same direction, which can be seen in ground footage.My idea was, that this angle of attack is maybe used to generate lift. I talked with others in another Forum about this, but it seems im alone with what i think is clearly visible and what i think could be the reason for. I know here are the greatest experts availabe for a normal person like i am... so may i ask for help about this point? Im of course happy to learn that im wrong with my impressions Thank you all very much in advance!Greetings
I'm not saying you are wrong about the pitch changes, but you do need to be careful of camera angles. What you are seeing could be primarily an artefact of the increasing range, coupled to a yaw manoeuvre, or a combination of yaw and pitch.
Quote from: STS-200 on 06/12/2021 09:36 pmI'm not saying you are wrong about the pitch changes, but you do need to be careful of camera angles. What you are seeing could be primarily an artefact of the increasing range, coupled to a yaw manoeuvre, or a combination of yaw and pitch.Hi STS-200,thank you for your reply and your thoughts. I fully understand what you say and yes, if this camera angle would be the only one showing the effect, i would be with you. But the effect, deviation of plume and change of pitch in relation to the horizon, can cleary be seen in onboard footage too. As an example, here is a star link launch from 2021-05-04:...Take a look at the plume and the horizon of earth relative to the rocket body. The plume is very symmetrical until around T+ 01:30. Roughly at that point, the plume starts to shift slighty to the left (which is, in this video, upwards... or in other words, the pitch of the rocket body seems to go upwards). While there seems to be no real noticable change in relation of horizon line and rocketbody, the effect of shifted plume is increading over time. It becomes - at least for my eyes - very obvious at around T+ 01:50 and even more from T+ 02:00 on up to around T+ 02:25 (roughly). Then it gets very interesting. In the timeframe T+ 02:26 to T+ 02:27 there is a sudden shift of rocketbody in relation to the horizon. The rocket seems to be pitching back to what seems zero angle of attack in the ground footage. Sadly then there is a swap to another cam onboard, inside the interstage. i would have loved to have the view of the outside of the rocket for 3 sec longer. But anyway, my point is: Onboard footage seems to match what can be seen from ground footage, even though these are two different launches. And i found a lot of other launches with more or less same behaviour (either from ground or onboard footage). So i tend to think, that the observation is not an artifact of camera angle, but something real.But still, im happy to learn that im just plain wrong of course GreetingsExcalibur
Useful chart from NASA’s Launch Services Program presented at today’s planetary sciences decadal survey steering committee meeting, comparing performance of launch vehicles at several C3 (characteristic energy) values.
For comparison, performance of various SLS versions from a separate presentation at the meeting (doesn’t assume additional kick stages).
Accurate. Show that Falcon Heavy addresses all use cases.
OK, yes this video does make it much clearer what is going on. It is not a camera angle issue, but it isn't actually a pitch-up either.At about 1:30, the rocket's pitch rate drops significantly, perhaps to zero. As you noted yourself - before this you can see the horizon shift in the view as the rocket slowly pitches down, then the view stops changing.There is no pitch-up, there is just an absence of pitch-down.At constant pitch, the AoA will gradually increase as the rocket's velocity vector becomes more horizontal (it is still accelerating upwards, but it is accelerating downrange much more quickly). As AoA increases, the plume will appear to become slanted relative to the rocket, as once the the exhaust gases have left the engine nozzles, they are deposited into the atmosphere along the path of the rocket's flight (i.e. along the velocity vector, which is not in the same direction the rocket is pointing, due to the AoA).As you say, just before the view changes at about 2:26, the rocket starts to pitch down again; this would be the start of the manoeuvre to return to a low AoA for staging and the early part of 2nd stage flight.
