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24

The test they were doing didn’t require parachutes. Data-taking ended right after the capsule separated from the tower. Since the capsule’s behavior after that was not part of the test, it could be an inert item. To extend the test through parachute deployment, the capsule would have to be much more complex with the parachutes, deployment system, and a ...


19

Lower orbits are faster, higher is slower, so by adjusting orbit altitude you can get an orbit that gains or lags until you are in position do execute a Hohmann transfer. The orbit period is around two hours and the velocities involved around a mile a second so 1000 miles does not have to take that long to close up. Especially if you get both craft change ...


17

No. I think this is actually the May 23, 1965 A-003 test, described in my answer to the question, Could a spacecraft spin so fast that it spontaneously deconstructs? Notice that the rocket and Apollo CM are spinning. That isn't supposed to happen. In A-003, improperly installed gyros caused the vanes on the fins to deflect fully in one direction, imparting ...


16

There were specific procedures for an abort at any time during the powered descent and after landing. The abort case at the planned time of landing (about 12 minutes after PDI) is covered in this chart: It is from the LM Rendezvous Procedures - G Mission PDF page 78. It's a bit crowded, but it shows the relative profile between CSM and LM, centered on the ...


15

From the article: Tuesday’s launch was more focused on testing the launch abort system itself. The parachutes on Orion have been tested 47 times.


12

There are no published/proposed abort modes for ascent. We can speculate that some incidents can be survived by letting Starship tumble free and light it's own engines to burn to a low orbit or land depending on altitude and velocity, but that capability has not been proposed by SpaceX. Landing redundancy is provided by carrying 7 deep throttling, sea level ...


12

This is not a complete answer as I do not know the status of the parachute development, but here are some reasons a parachute is not needed: Ejected Data Recorders: These ~20 data recorders, literally Raspberry Pis with parachutes and waterproofing, all get the complete telemetry data from the test. This is made up of accelerometer, gyroscope, magnetometer ...


11

Here's an official response: NASA has already fully qualified the parachute system for flights with crew through an extensive series of 17 developmental tests and 8 qualification tests completed at the end of 2018. Test data from 890 sensors was sent in real-time to ground sites as well as recorded on board by 12 data recorders. The 12 data recorders ...


11

It seems that someone on the /r/spacexlounge subreddit had the same question: We know from the FAA filing for the pad abort that Dragon has a fuel capacity of 1388kg, and we know that it's max landing mass should be around 8.9 tonnes. If we round that up to 9 tonnes, and then plug in the specific impulse for SuperDraco of 235 seconds, we get a Delta-...


8

It was impossible to restart the engines in flight. If for no other reason, the pressure/temperature conditions for the "start box"1 were not met in flight. Also, Post Shutdown to Engine Ready was not a legal transition in the controller flight software. There were also considerations of engine drying (removal of residual water after shutdown), prelaunch ...


7

Please refer to this diagram while reading this answer. You mentioned modification of the first stage trajectory in response to initiation of an RTLS abort; this was in fact allowed for, within the stringent constraints of the first stage ascent. A pitch bias would be added to the pre-programmed pitch attitude to loft the trajectory above the nominal. You ...


7

Here is a graphic og the ascent and landing profile that shows the default to water trajectory, with the "corrected" landing if the computer determines all is well.


6

The Block 5 Falcons uses a new system called AFT (Autonomous Flight Termination) that is run by the booster, not the flight safety officer any longer. Additionally you can hear them call out during launch that the flight termination system is safed on the way up, before the booster tries to land. The theory is the booster is basically empty at that point ...


6

To be fair, I asked, so I could answer, so it would be ready when people come looking. SpaceX aims at the water, away from the actual landing point (pad, barge, whatever) and only diverts if all is going well. They thought about this exact circumstance in advance and it worked well. They did not need to divert away as they were not yet aimed at the landing ...


6

Really this is several questions. Launch abort, and landing abort/recovery questions. Launch abort, there is not yet a lot of good answers, and may have to wait for future information. Landing abort we know they intend to land on at least 3 engines, which they changed from 2 to 3 in the various iterations. This is designed to allow engine out on landing. ...


3

Your question is based on a misunderstanding- the External Tank propellant tanks did in fact have relief valves. The 02 valve relieved at 24 psid and the H2 valve relieved at 36 psid. From the 1982 Press Manual, pages 92-95 GremlinWrangler's comment about the inadvisability of venting hydrogen is well founded - see Flight Rule A5-154 whose rationale ...


3

Using Super Dracos, yes. Musk quotes from the thread: Dragon 2 was designed to land using thrusters, with parachutes as backup. Switched to chutes as primary, due to difficulty of proving safety, but Dragon can still do it. https://t.co/Mr7VFIQwWf ... For cargo missions, propulsive land landing should be no problem. Doesn’t have same safety ...


2

I can't place when he said this, but I remember, Musk was asked about this in some interview. He said it could land propulsivly, but it would be a hard landing because the landing gear that was originally planned is not there. He did not indicate if they had programmed that option into the return sequence. It sounded to me like a theoretical answer. ...


1

The parachutes and the heat shield were already tested with the EFT-1 launch, in 2014, with a real capsule!


1

Because a massive Saturn V (or even a Saturn IB) can't tumble 260 °/s like a Little Joe can. Even if it could, the abort system is triggered at 20 °/s: Within 2.5 seconds after lift-off, a launch vehicle malfunction caused the vehicle to go out of control. The resulting roll rate caused the launch vehicle to break up before second-stage ignition,...


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