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I know that, Crew Dragon was initially designed for vertical landing on solid surfaces, as a reusable spacecraft, and then some changes were made to make it capable of landing in water using parachutes, as a non reusable module.

Crew Dragon landing

Crew Dragon landing

Instead of detaching from the main thrusters (as the bell of Soyuz), Crew Dragon lands together with the main engines and tanks of fuel also they serve no purpose once the parachutes are deployed, more precisely once the capsule enters the atmosphere. On the contrary they make the lander heavier.

Boeing CST-100 Starliner seems to be a much clever design than Crew Dragon, in theory even better than Soyuz because it has only two instead of three modules. CST-100 can land both on water and on the ground and only the bell comes down to earth without the main thrusters as in the case of Crew Dragon.

Am I right or I am missing something?

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    $\begingroup$ I think it would be good to rephrase the question title to be about the landing system itself or the fuel for propulsion vs parachute rather than dragon as a whole $\endgroup$
    – Speedphoenix
    Jun 5, 2020 at 21:25
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    $\begingroup$ Can you explain why you think not throwing away the most expensive parts of the vehicle is "flawed"? I have a hard time following your logic. $\endgroup$
    – Jörg W Mittag
    Jun 6, 2020 at 7:48
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    $\begingroup$ Those expensive parts are useless if they are not reusable. It does not make too much sense to land with them and then throw them because the heavier the landing capsule is the more parachutes and heavier reentry shield it has to use. $\endgroup$
    – user16613
    Jun 9, 2020 at 9:12

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It seems like you are considering design for re-use as a flaw.

The Super Draco engines are kept since they can be reused. They need them for abort, so unless they ditch them, they cost payload mass to support them.

The CST-100 needs a new service module for each flight with new engines and whatnot, versus the much simpler/cheaper trunk the Dragon needs.

CST-100 drops its heat shield to expose the landing air bags, so it needs a new one for each mission.

Basically SpaceX designed Dragon for more complete reuse than Boeing did with the CST-100. This makes sense, since SpaceX is flying on a reusable first stage and CST-100 flies on an entirely discarded booster (Atlas V).

In your question title, you ask if Dragon is an improvisation with no future, which is actually different I think than the body of your question. Dragon is actually a dead end. It will only ever fly a few dozen missions.

Starship will very quickly eclipse Dragon once it starts flying. However it is a logical extension of an existing vehicle, and is necessary tool until something better is available. If you like, imagine the Atlas 3. It was the step stone to the Atlas 5 and had no real future, but proved out technologies and ideas.

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    $\begingroup$ Do you know the landing mass of Crew Dragon, CST-100 Starliner and Soyuz? $\endgroup$
    – user16613
    Jun 5, 2020 at 19:05
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    $\begingroup$ @RobertWerner African or Eurpoean (Monty Python joke). Do you mean dry mass on landing, or returned payload mass? $\endgroup$
    – geoffc
    Jun 5, 2020 at 19:19
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    $\begingroup$ I mean the total mass (including that of the parachutes) the three capsules have when they touch the surface of Planet Earth, after coming back from space. $\endgroup$
    – user16613
    Jun 5, 2020 at 19:29
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    $\begingroup$ @RobertWerner That sounds like a good question. Why don't you ask it? Betcha get some upvotes and points for it. :) $\endgroup$
    – geoffc
    Jun 5, 2020 at 19:48
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    $\begingroup$ @geoffc: "Starship will very quickly eclipse Dragon once it starts flying." - Why is that? $\endgroup$
    – pat3d3r
    Jun 8, 2020 at 7:00
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First of all, Crew Dragon can actually be reused. NASA has agreed to permit reuse of both rockets and the capsule after the second longer-term mission.

Of some note, the capsule was always designed to land with parachutes, they were only going to be a backup system. As it stands now, the propulsion is the backup system and the parachutes are the main system.

The fuel doesn't go to complete waste. Crew Dragon has a common fuel tank for emergency use as well as the smaller thrusters that point it in the right direction and do orbital maneuvering. The only wasted part is the engines, which is a fairly small weight really.

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    $\begingroup$ If Crew Dragon is really reusable (but we have to be sure) then the design is not flawed, at least in theory. $\endgroup$
    – user16613
    Jun 5, 2020 at 19:03
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    $\begingroup$ The question is how reuseable. But in any case, it will almost certainly be more reusable than Soyuz. $\endgroup$
    – PearsonArtPhoto ♦
    Jun 5, 2020 at 19:30
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If I remember correctly Spacex wanted Crew Dragon to land on legs, but NASA would not approve this design, only parachute landing. This is why the Engines are built in. Maybe NASA will approve this method one day.

Source (partial): https://spaceflightnow.com/2017/07/19/propulsive-landings-nixed-from-spacexs-dragon-spaceship/

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    $\begingroup$ Sources, please. $\endgroup$
    – DrSheldon
    Jun 5, 2020 at 21:19
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    $\begingroup$ "Propulsive landings nixed from SpaceX’s Dragon spaceship" (spaceflightnow.com/2017/07/19/…) $\endgroup$
    – user16613
    Jun 6, 2020 at 8:32

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