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I'm not an engineer (well not that kind), but it seems to me relying wholly on thrusters seems kind of iffy on being fully stable... wouldn't maybe having the r

I'm not an engineer (well not that kind), but it seems to me relying wholly on thrusters seems kind of iffy on being fully stable... wouldn't maybe having the rockets slow down the craft to the point where drones could lasso it, or connect to it, or even built in wings could expand with copter blades to steady it and lower it down more gentle? I mean early space-flight used parachutes, that's an option too though I'd imagine a space capsule weighs a shit ton less.... I just wouldn't trust my family on a rocket like this, feels very pre-mature. Like there's something missing to ensure it doesn't do a back flip at the end...per se.

Nekhrimah 6y ago
Starship is being designed to land on Mars. Therefore it needs to land safely with only what comes with the vehicle. Note Mars atmosphere is 1% pressure of Earth.
NortySpock 6y ago
https://www.youtube.com/watch?v=OIuGfXp-Ok8 https://www.youtube.com/watch?v=OIuGfXp-Ok8 Helicopter blades have been proposed and tested, but apparently Roton, an early space company, did not have nearly enough money. Also they pursued a SSTO platform that they didn't have the efficiency margins to pull off.
- colordrops 6y ago
  Holy crap, so that's what the craft in Kin Dza Kza are based on: https://medium.com/@andreifyodorov_65581/kin-dza-dza-was-directed-by-soviet-georgian-filmmaker-georgy-danelia-in-1986-7dc95f08c7ef https://medium.com/@andreifyodorov_65581/kin-dza-dza-was-dir... Amazing movie by the way.
mLuby 6y ago
(I don't understand the downvotes; you're asking the same reasonable questions that I'm sure Elon asked too.) From what I've read, passive landing solutions like parachutes, wings, rotors, air bags, etc. are feasible only for smaller payloads. Think Apollo/Soyuz capsules, or the first couple Mars landers, or RocketLab's Electron rocket with a parachute. I'm sure the JPL engineers would have preferred a tried-and-tested passive parachute (and maybe some airbags) over a sky-crane, but the latest rovers are just too heavy for safe parachute landing. I believe it's the same situation with Falcon 9 and Starship recovery. And remember that SpaceX's Dragon capsule demonstrated an impressive propulsive landing, but NASA said no thanks and required parachutes.
nickik 6y ago
You are not the first to think about this. You need to consider how freaking gigantic this thing is. It literally like a huge building falling out of the sky. That scale alone makes most of these solutions silly. Here for example NASA idea for the Saturn V: https://thespacereview.com/archive/3741a.jpg https://thespacereview.com/archive/3741a.jpg The problem with ideas like this is that you have to develop another huge difficult large scale engineering project. That you need to maintain, update operate and so on. And even if you do that, is this gigantic device actually more stable then just relaying on your well tested well engineered rocket engine? On smaller vehicles you can do air capture because you can use commercial helicopters. See RocketLab doing this currently: https://cdn4.dogonews.com/images/e97aac75-0e4b-442e-b484-a71ab50d1b9d/dims-5.jpeg https://cdn4.dogonews.com/images/e97aac75-0e4b-442e-b484-a71... Now, parachutes simply don't scale that large. It simply doesn't work. > I just wouldn't trust my family on a rocket like this, feels very pre-mature. Like there's something missing to ensure it doesn't do a back flip at the end...per se. Well it is pre-mature. Nobody denies this. This is the first vehicle ever to fly a Full-Flow Stage Combustion engine. Its one of the single biggest flying devices ever made by humans. It uses a re-entry procedure that has never been done before. With a combination of structure and heat shield that has never been done before. With a landing maneuver that has never been done before. This will likely fly 100 times before humans get on it, and then only astronauts. All that said however, there is no inherent reason why relaying on your engine and thrusters should be unstable. You can have redundancy in those systems.

Nekhrimah 6y ago

Starship is being designed to land on Mars. Therefore it needs to land safely with only what comes with the vehicle. Note Mars atmosphere is 1% pressure of Earth.

NortySpock 6y ago

https://www.youtube.com/watch?v=OIuGfXp-Ok8 https://www.youtube.com/watch?v=OIuGfXp-Ok8 Helicopter blades have been proposed and tested, but apparently Roton, an early space company, did not have nearly enough money. Also they pursued a SSTO platform that they didn't have the efficiency margins to pull off.

colordrops 6y ago
Holy crap, so that's what the craft in Kin Dza Kza are based on: https://medium.com/@andreifyodorov_65581/kin-dza-dza-was-directed-by-soviet-georgian-filmmaker-georgy-danelia-in-1986-7dc95f08c7ef https://medium.com/@andreifyodorov_65581/kin-dza-dza-was-dir... Amazing movie by the way.

mLuby 6y ago

(I don't understand the downvotes; you're asking the same reasonable questions that I'm sure Elon asked too.) From what I've read, passive landing solutions like parachutes, wings, rotors, air bags, etc. are feasible only for smaller payloads. Think Apollo/Soyuz capsules, or the first couple Mars landers, or RocketLab's Electron rocket with a parachute. I'm sure the JPL engineers would have preferred a tried-and-tested passive parachute (and maybe some airbags) over a sky-crane, but the latest rovers are just too heavy for safe parachute landing. I believe it's the same situation with Falcon 9 and Starship recovery. And remember that SpaceX's Dragon capsule demonstrated an impressive propulsive landing, but NASA said no thanks and required parachutes.

nickik 6y ago

You are not the first to think about this. You need to consider how freaking gigantic this thing is. It literally like a huge building falling out of the sky. That scale alone makes most of these solutions silly. Here for example NASA idea for the Saturn V: https://thespacereview.com/archive/3741a.jpg https://thespacereview.com/archive/3741a.jpg The problem with ideas like this is that you have to develop another huge difficult large scale engineering project. That you need to maintain, update operate and so on. And even if you do that, is this gigantic device actually more stable then just relaying on your well tested well engineered rocket engine? On smaller vehicles you can do air capture because you can use commercial helicopters. See RocketLab doing this currently: https://cdn4.dogonews.com/images/e97aac75-0e4b-442e-b484-a71ab50d1b9d/dims-5.jpeg https://cdn4.dogonews.com/images/e97aac75-0e4b-442e-b484-a71... Now, parachutes simply don't scale that large. It simply doesn't work. > I just wouldn't trust my family on a rocket like this, feels very pre-mature. Like there's something missing to ensure it doesn't do a back flip at the end...per se. Well it is pre-mature. Nobody denies this. This is the first vehicle ever to fly a Full-Flow Stage Combustion engine. Its one of the single biggest flying devices ever made by humans. It uses a re-entry procedure that has never been done before. With a combination of structure and heat shield that has never been done before. With a landing maneuver that has never been done before. This will likely fly 100 times before humans get on it, and then only astronauts. All that said however, there is no inherent reason why relaying on your engine and thrusters should be unstable. You can have redundancy in those systems.