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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 ...


24

It was a real failure (albeit triggered externally rather than accidentally), just not the only failure that can happen. and it is the worst case of a series of the most likely failure scenarios: multiple engine failure. If you want to test every conceivable way a rocket can fail, you're looking at thousands if not hundreds of thousands of possible failure ...


19

You seem to think they were testing in ideal conditions. That's as far from truth as you can get. The abort happened at the moment in flight with worst aerodynamical conditions (called maxQ), when booster flies still low enough in atmosphere for significant drag to be present, yet fast enough already. If Dragon can escape at this moment, it can escape at any ...


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 ...


18

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

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 ...


8

No. One of NASA's requirements for Crew Dragon and Starliner is that they are able to provide a full envelope abort window for the launch. 5.6.1.2 The CCTS shall provide abort capability from the launch pad until orbit insertion to protect for the following ascent failure scenarios (minimum list): a. Complete loss of ascent thrust/propulsion. b. ...


5

I have not yet found the abort limit figure. According to Saturn V AS-507 "G" Mission Launch Vehicle Operational Flight Trajectory - September Launch Month (a trajectory planning document for Apollo 12), the peak Qɑ for a nominal flight would be between 18 and 22 kNº/m^2 (= kPaº):


5

In the post-launch media event with Jim Bridenstine and Elon Musk, a similar question was asked and Elon said that the capsule would be able to "fly through the fireball" and explained how that even in a critical failure, the Falcon 9 doesn't really explode, rather it causes a huge fireball (no big pressure wave). Additionally, it was mentioned that the ...


3

I think you are working from a faulty assumption here. ...if the booster engines were still firing, would it collide with Dragon? If the booster engines are still firing, there's no reason to trigger the escape -- other than severe control malfunction (a la Ariane 5), which wasn't what was tested here. Any kind of failure of the booster that is not a ...


3

Partial answer to help bound the values: The SA-507 Flight Manual page 3-9 says the nominal meter indications shouldn't exceed 25% to 50% of the limit. With the max nominal numbers in the other answer of 20 kNº/m^2 that puts the limit somewhere between 40 - 80 kNº/m^2.


2

Forget about the SRBs, they play no role in an abort. You don't even select the RTLS abort until after SRB sep. The earliest RTLS selection is made at 2m30s allowing time for SRB sep induced transients to be damped out, and for second stage guidance to converge. Therefore, an abort could be initiated before SRB sep, but the vehicle would not begin ...


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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