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Why don't they already carry payloads? Is there anything worth taking up with the current expected value of it exploding ect?
by icpmacdo 2y ago
Why don't they already carry payloads? Is there anything worth taking up with the current expected value of it exploding ect?
- antoniuschan99 2y agothey carried a banana this time :)
- deleted 2y ago[deleted]
- ethbr1 2y agoIs the Starship upper stage boosting itself up to full orbit yet?
- deleted 2y ago[deleted]
- fastball 2y agoOrbit is not about distance, it is about speed (perpendicular to gravity). Starship deliberately did not reach orbital velocity on this flight, so although they are fairly certain it is capable of doing so (esp after testing engine relight on this flight), they have not done it yet. Not being at orbital velocity is one reason why they are not delivering payloads. The reason for choosing not to go orbital at this point is indeed as another commenter said: safety. A craft which has not reached orbital velocity is therefore traveling on a parabola, which has a predictable flight path. If they lose control of all systems, they can still be confident that it will crash where they want it to (in this case, the Indian Ocean). If instead you boost enough to get orbital and then lose control, it is much harder (almost impossible) to know where the craft will end up. SpaceX (and the FAA) wants to make sure everything works properly by doing sub-orbital flights, then when they are fairly confident nothing will completely break on them they can start testing in an orbital regime, by powering on Starship's engines long enough to achieve the requisite speed.
- fixprix 2y agoThey don't need to relight to reach orbit, they just performed SECO a bit early. For reference at 190 km up which Starship reached, it needs to go 28,000 km/h to stay in orbit. Today it was flying at 26,000 km/h.
- hnaccount_rng 2y agoBut then they’d need to relight in order to break orbit. So technically correct ;)
- mgsouth 2y agoNo. This and all previous flights have intentionlly been barely sub-orbital, with less than one orbit. Launch in Texas, re-entry over Indian Ocean. A full orbit at that altitude takes about 90 minutes; this was over in a little over an hour. The reason was safety. If it was orbital, then controlling the re-entry would require a sucessful relight of the engines. If that failed then the re-entry point would depend upon the vagaries of orbital decay from residual atmospheric drag. That's no doubt why today's relight was so brief; they didn't want to significantly alter the reentry point.
- deleted 2y ago[deleted]
- mohaine 2y agoI don't believe this is quite correct. The last few trips are actually orbital, just not of the correct elliptical shape to do more than a half orbit as the perigee is less than the radius of earth. If earth was a point mass, it would have orbited. This means you don't have to do anything to deorbit while proving you could have made a full orbit if you wanted to.
- Toutouxc 2y ago> the perigee is less than the radius of earth Which is what we call "sub-orbital" :)
- gpm 2y agoIf the earth suddenly became a point mass except for all the humans, we'd all already be in orbit. At the "top" of a highly elliptical orbit that passes relatively close to that point mass, yes, but an orbit. Everything that was within the Earth's sphere of influence, not moving so fast to be on an escape trajectory, and not with 0 horizontal velocity relative to the point mass would be in an orbit. Orbital means "on a trajectory that doesn't intersect (or escape from) the body you are orbiting", otherwise the word is meaningless.
- kbelder 2y ago
- nomilk 2y agoThe utility of test flights doesn't come from delivering a payload; but from collecting data. For example today's test involved intentionally weakening starship's heat shield to see if previous estimates of required shielding had been too conservative.
- soheil 2y agoWell looks like you imposed a qualification on these types of flights and now by definition they cannot deliver payload. The flights could deliver cheap payload for example.
- AlessandroF6587 2y ago"The payload is data." Elon The data they get from the test and they focus on getting the most and most valuable data. This is an explicit choice. A physical payload at this stage would reduce the overall value that they are able to get from a flight.
- cwillu 2y agoYou can't deliver a payload to orbit if you're not planning on going to orbit. They have a launch licence for a particular mission plan. The license for Falcon 9 and Falcon Heavy specifically says “Authorization: SpaceX is authorized to conduct flights of launch vehicles: […] (c) Transporting Dragon 2 to low Earth orbit or a payload to orbit;” The license for Starship/Super Heavy Launch Vehicle does not include such an authorization. https://www.faa.gov/media/69476 https://www.faa.gov/media/69476 https://www.faa.gov/media/75501 https://www.faa.gov/media/75501
- gpm 2y agoSpeculation: Putting a starship in low earth orbit right now would be a bit reckless, because if the engines fail to relight it's going to come down at some point in a completely random spot along the trajectory, and it's quite a large piece of debris that is designed to not burn up. By contrast this test (which involved the first 0g relight of a raptor) was designed so that if that failed the ship would still come down in a designated keep out zone in the ocean. Even ignoring the safety risk, the value SpaceX gets from this flight is largely testing the re-entry (heatshield, flaps, etc) of starship. Putting it in an orbital trajectory risks a failed engine relight making it impossible to test that, because the ship will be dead (out of power) by the time it comes back down. Whatever low-cost payload you could put up there for "free" (the cost of risking the payload being destroyed if the test flight goes wrong too early) might not be sufficient to pay for the risk stopping in an orbital trajectory imposes on the test objectives. Now that they've successfully lit a raptor in 0g, I imagine they're a fair bit more likely to make the subsequent flights orbital.
- PittleyDunkin 2y ago> Putting a starship in low earth orbit right now would be a bit reckless, because if the engines fail to relight it's going to come down at some point in a completely random spot along the trajectory, and it's quite a large piece of debris that is designed to not burn up. More relevantly—it's harder to make a marketing stunt out of a fallible mission.
- rogerrogerr 2y agoIs it your position that flight 6, or the Starship program, or SpaceX is a marketing stunt?
- deleted 2y ago[deleted]
- MarkusQ 2y agoWhat exactly do you think they're marketing? And don't say launch services, 'cause you're using "it's a marketing stunt" to explain why they aren't taking payloads. "It's R&D" makes a heck of a lot more sense.
- baq 2y agoTheir payload door situation is complicated.
- busssard 2y agocan you elaborate? https://ringwatchers.com/article/ship-pez-dispenser https://ringwatchers.com/article/ship-pez-dispenser Seems like their door is made exactly for the purpose of dispensing starlink satelites, with minimal impact to the hull integrity..
- baq 2y agoThe first time they tested it in space it didn't open and they haven't tested since. I don't expect this to be a major showstopper but obviously they must figure it out before they can start making money off of starship.
- modeless 2y agoIt's exactly because they hadn't demonstrated engine relight in space yet. That means they couldn't guarantee they would be able to deorbit Starship in a controlled way. An uncontrolled deorbit would be bad because it could come down literally anywhere and large chunks would hit the ground. Because they couldn't guarantee precise deorbiting, they never put it in orbit to begin with. Starship was on a ballistic trajectory that falls back to Earth. Any payloads they deployed would fall back too, unless they carried their own rockets to reach orbit themselves.
- chippiewill 2y ago> Starship was on a ballistic trajectory that falls back to Earth Actually Starship on this flight wasn't quite on a ballistic trajectory, the periapsis was actually above the ground so it counts as an orbital trajectory. Without the atmosphere it would keep going.
- adastra22 2y agoLots of technical speculation in the sibling comments. I suspect the real answer is that any real payload would require at least FCC approval, and possibly modification of their FAA flight plan. The income from the payload would not be worth the delay.
- hoschicz 2y agothey showed a banana in the payload bay, that was the testing payload:) they pushed the rocket to the limits in this flight
- Treegarden 2y agoFrom what I followed, its because: They already send payload to space with the falcon rockets (reliable cash cow) and the only point of starship system is proof of concept of full reusability. There is no point to the whole project if they dont achieve this. They are constrained in launches, either through regulatory (FCC) or engineering timeline and so far, every launch counted. They achieved a substantial improvement. If they dont catch the starship (upper stage), the whole project is pointless so its important keep things simple (details like payload door, cargo dont matter) until they achieved the whole loop (land & catch starship) They already have a cheap way of launching. Cheap for current market rate. Whole point of this project is to improve cost by / 1000. They achieved substantial progress with every flight. 1. It flies, 2. hot staging 3. reach orbit 4. land both & heat shield, 5. catch booster, 6. extreme conditions & improve heat shield.