Interesting that John Insprucker mentioned on the Iridium launch webcast that the ASDS does *not* send any signals to the returning stage; it only receives telemetry from the stage.We have known this pretty much from the beginning, but some people were skeptical, so it's worth noting that we now have confirmation of the fact directly from SpaceX.
Quote from: Kabloona on 06/26/2017 06:37 pmInteresting that John Insprucker mentioned on the Iridium launch webcast that the ASDS does *not* send any signals to the returning stage; it only receives telemetry from the stage.We have known this pretty much from the beginning, but some people were skeptical, so it's worth noting that we now have confirmation of the fact directly from SpaceX.Yes, good to have that confirmation. I would still like to know why. Is it because of some patent issue or just because they do not see any advantage in two way communication.
Yes, good to have that confirmation. I would still like to know why. Is it because of some patent issue or just because they do not see any advantage in two way communication.
Quote from: guckyfan on 06/26/2017 06:44 pmQuote from: Kabloona on 06/26/2017 06:37 pmInteresting that John Insprucker mentioned on the Iridium launch webcast that the ASDS does *not* send any signals to the returning stage; it only receives telemetry from the stage.We have known this pretty much from the beginning, but some people were skeptical, so it's worth noting that we now have confirmation of the fact directly from SpaceX.Yes, good to have that confirmation. I would still like to know why. Is it because of some patent issue or just because they do not see any advantage in two way communication.Because there's no good reason. ASDS positioning and F9's GPS accuracy seem to be the last of their worries.
It's far easier to get an accurate position of a fixed barge than a moving ship. However, a moving ship could provide a more stable platform in rough seas for a larger scaled vehicle, as well as a more rapid return or longer downrange (lofted, "gentler" EI (no entry burn) using less props for more efficient boost(lifting not ballistic, higher drag/alpha) ).
i swear i heard that droneship at least sends windspeed data to stage
Quote from: drzerg on 06/26/2017 11:07 pmi swear i heard that droneship at least sends windspeed data to stageNo. Many people have speculated that it does or insisted it "needs to" so many people have believed that. But there has never been any evidence from a credible source to support the idea that the ASDS sends information to the ASDS rocket.
Quote from: Kabloona on 06/26/2017 06:37 pmInteresting that John Insprucker mentioned on the Iridium launch webcast that the ASDS does *not* send any signals to the returning stage; it only receives telemetry from the stage.We have known this pretty much from the beginning, but some people were skeptical, so it's worth noting that we now have confirmation of the fact directly from SpaceX.His exact words were "The drone ship does not send commands to the first stage in flight." That leaves open whether or not commands are given to the stage after it lands, perhaps as part of safing it. I'm not sure why that would be necessary though: the safing process could and probably should be entirely automatic. After all, the rocket knows when it has landed.
Quote from: Kabloona on 06/26/2017 06:37 pmInteresting that John Insprucker mentioned on the Iridium launch webcast that the ASDS does *not* send any signals to the returning stage; it only receives telemetry from the stage.We have known this pretty much from the beginning, but some people were skeptical, so it's worth noting that we now have confirmation of the fact directly from SpaceX.Corollary. Why does the ASDS need to receive telemetry from the stage? It knows it's on its way, it doesn't need to move, it doesn't need to know anything.
Sorry if I missed it in this mass of ASDS threads, but has there been any attempt made at an estimate of total cost of ASDS, barge + materials + thrusters + avionics + paint etc. I.E. what might SpaceX insure them for (assuming they could get insurance for something they are actively targeting with multiple tons of incoming ballistic "missile") or what might it cost them to replace from the ground up? I think when they were first announced (ASDS in general) I made a super rough estimate of $3m for a Marmac, $1m for the steel deck plating, $500k for the thrusters, and another $500k for labor, paint and fuel, plus $250k for towing for the first landing attempt mission. Anyone else have any guesses or adjustments?
Since each ASDS has caught one stage... that later has reflown... (two reflown to date)I think we can safely say that both are nearing cash positive on the Spacex books... all in...
Quote from: JamesH65 on 06/27/2017 10:16 amQuote from: Kabloona on 06/26/2017 06:37 pmInteresting that John Insprucker mentioned on the Iridium launch webcast that the ASDS does *not* send any signals to the returning stage; it only receives telemetry from the stage.We have known this pretty much from the beginning, but some people were skeptical, so it's worth noting that we now have confirmation of the fact directly from SpaceX.Corollary. Why does the ASDS need to receive telemetry from the stage? It knows it's on its way, it doesn't need to move, it doesn't need to know anything.In this case, the ASDS serves as a data relay for SpaceX, since by the time the stage is closing in on the ASDS, it is below the horizon from the launch pad.