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by zlsa 2423 days ago
SpaceX originally planned to develop a [propulsive landing system](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), a plan to send uncrewed Dragons to the surface of Mars, along with it.)

2 comments

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...

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?
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.

Because landing on land allows for faster retrieval of the astronauts and cargo, and is better for the capsule.