14 ms·
Not yet, not until re-entry. It's arguably the most dangerous part of the missions since launching on Falcon 9 has happened many times before. Both Soyuz and t
by kanox 6y ago
Not yet, not until re-entry. It's arguably the most dangerous part of the missions since launching on Falcon 9 has happened many times before.
Both Soyuz and the Space Shuttle had fatal accidents on re-entry.
- boardwaalk 6y agoI don’t believe SpaceX has ever not tried and succeeded to return a Dragon sent to ISS back to Earth.
- Robotbeat 6y agoThat is true, but it has only had one successful reentry (one out of one attempts) of a Dragon Crew capsule design (which, granted, is only slightly different than Dragon Cargo).
- chrisweekly 6y agoFor clarity: I think "tried and not succeeded" is the intended phrasing.
- boardwaalk 6y agoI meant “not (tried and succeeded).” English is great.
- caconym_ 6y agoYou're not wrong, but I think it's cool how much safer the generic capsule design is than something like the Shuttle. Really the Shuttle got a whole lot wrong—heat-intolerant aluminum structure and critical, sensitive machinery directly beneath a layer of tiles so fragile you can crush them in your hands (IIRC). SpaceX's Starship will probably be a lot more tolerant to defects in the heat shield because of the relatively heat-tolerant steel underneath, but landing safely relies on the operation of massive aero surfaces and a relight of the engines with thrust vectoring. It'll be interesting to see how that goes.
- zitterbewegung 6y agoThis is at the stage where you cant really make assumptions about what may happen because you don't know what could go wrong. (A.K.A you don't know what you don't know).
- free_rms 6y agoI'm not claiming that OP or I are experts, but there's actually a pretty big body of knowledge for capsule re-entry. It's more 'known problems' than 'unknown unknowns'.
- caconym_ 6y agoAll you need to bring a traditional capsule design down to ~sea level terminal velocity safely is a blunt body with offset CG and the kind of circular ablative heat shield that's been shown over decades to be simple, safe and reliable. You don't even need active control unless you want more precision for hitting your landing target. The biggest risk, assuming your position and velocity were correct at interface, is the parachutes–which is why SpaceX took so much time testing and refining them. Things can always go wrong, but we know enough about both classes of vehicle to be able to say that the Shuttle's design was in general terms both more complex and more risky. This is slightly off topic, but the Shuttle was horribly unsafe on the way up as well as on the way down. Using solid rocket boosters with no means to get the crew safely off the stack until they stop burning is, for lack of a better word, demented. The Crew Dragon/Falcon 9 stack offers realistic abort modes from the moment fueling begins until the vehicle reaches its intended orbit.
- one2know 6y agoThe Shuttle was built to bring down soviet spy satellites and spacecraft, so in that regard, it was the best design made.
- whoisthemachine 6y agoHuh interesting. Do you have sources for that information?
- diebeforei485 6y agoDragon has come back before (without crew) so this isn't a total unknown.
- manicdee 6y agoAfter reentry the next most dangerous part of the entire launch/return process is likely landing at sea and being rescued by helicopters or ships. So I will be holding my metaphoric breath until the astronauts are delivered from SpaceX responsibility to NASA responsibility, which should be on land somewhere in Florida (too lazy to look it up sorry not sorry)
- martyvis 6y agoThe Crew Dragon is very similar to the Cargo Dragon that has already had nearly 20 returns from orbit without incident, so there is already quite a bit of experience in the systems that will be used tomorrow.