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SpaceX originally planned to develop a [propulsive landing system](https://youtu.be/Cf_-g3UWQ04?t=90 https://youtu.be/Cf_-g3UWQ04?t=90), but this was dropped du

by zlsa 7y ago

SpaceX originally planned to develop a [propulsive landing system](https://youtu.be/Cf_-g3UWQ04?t=90 https://youtu.be/Cf_-g3UWQ04?t=90), but this was dropped due to several reasons: * The additional risks of a relatively untested system * Starship development had begun, which would make Dragon obsolete Propulsive landing of Dragon was therefore scrapped (and [Red Dragon](https://en.wikipedia.org/wiki/SpaceX_Red_Dragon https://en.wikipedia.org/wiki/SpaceX_Red_Dragon), a plan to send uncrewed Dragons to the surface of Mars, along with it.)

DuskStar 7y ago
Don't forget the biggest reason - the LES system used the same fuel as the propulsive landing system, and they only carried enough for one of the two. Which meant that landings after using the LES would require a parachute, and if you're carrying a parachute with you anyways why not just use it all the time?
- cameldrv 7y ago
  It seems to me that the parachute(s) you need for LES wouldn't need to be as complex and capable as landing parachutes. The LES parachute(s) will be firing at quite low speeds, so they don't need to be too strong. The LES parachute(s) also don't need to be nearly as reliable or give nearly as soft a landing. Ejection seats in combat aircraft show the same tradeoff -- it's considered acceptable to have ejection seats that fail sometimes and sometimes cause a landing injury. Hopefully you never have to use it, and so even if it fails or injures you say 10% of the time, it's much better than certain death in a pad explosion or similar.
- gpm 7y ago
  Because landing on land allows for faster retrieval of the astronauts and cargo, and is better for the capsule.
skunkworker 7y ago
The propulsive landing is still potentially a backup option to a parachute failure in the future. Q: Are thrusters programmed as backup if chutes fail to deploy properly? A: Most likely, but this is contingent upon NASA review & approval https://twitter.com/elonmusk/status/1104510803313487872?lang=en https://twitter.com/elonmusk/status/1104510803313487872?lang...

by zlsa 7y ago

DuskStar 7y ago

Don't forget the biggest reason - the LES system used the same fuel as the propulsive landing system, and they only carried enough for one of the two. Which meant that landings after using the LES would require a parachute, and if you're carrying a parachute with you anyways why not just use it all the time?

cameldrv 7y ago
It seems to me that the parachute(s) you need for LES wouldn't need to be as complex and capable as landing parachutes. The LES parachute(s) will be firing at quite low speeds, so they don't need to be too strong. The LES parachute(s) also don't need to be nearly as reliable or give nearly as soft a landing. Ejection seats in combat aircraft show the same tradeoff -- it's considered acceptable to have ejection seats that fail sometimes and sometimes cause a landing injury. Hopefully you never have to use it, and so even if it fails or injures you say 10% of the time, it's much better than certain death in a pad explosion or similar.
gpm 7y ago
Because landing on land allows for faster retrieval of the astronauts and cargo, and is better for the capsule.

skunkworker 7y ago

The propulsive landing is still potentially a backup option to a parachute failure in the future. Q: Are thrusters programmed as backup if chutes fail to deploy properly? A: Most likely, but this is contingent upon NASA review & approval https://twitter.com/elonmusk/status/1104510803313487872?lang=en https://twitter.com/elonmusk/status/1104510803313487872?lang...