These photos of SpaceX's Crew Dragon abort launch are just stunning

Jan 23, 2020
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Would this jettison escape system have work in a accident similar to Space Shuttle Challenger, where the the explosion occurred while the command vehicle was still attached to booster..ie not jettison first?
 
Nov 25, 2019
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Would this jettison escape system have work in a accident similar to Space Shuttle Challenger, where the the explosion occurred while the command vehicle was still attached to booster..ie not jettison first?

No. The shuttle was destroyed by aerodynamic force when one booster attachment point failed and caused the shuttle to yaw. The shuttle was not designed for air hitting from the side and broke up.

When you have an aircraft with a node and wings and tail it MUST be kept pointed "nose to the wind" or the structure fails.

When you have two solid boosters that are side by side there is nothing to do if one fails. The asymmetric thrust will break up the vehicle.

Back in the 70s Aerospace Corp. calculated that there would be a 2% failure rate for shuttles. This was the best estimate. NASA did not like the answer and buried the study. But it turned out to be about right. There is no good way to abort a shuttle launch. Only a few minutes of the launch is abortable for most minutes the result is "everyone dies". This is why they retired the shuttle. There was no possible fix and they would just have to cancel it or accept a 2% loss.
 
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Jan 23, 2020
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Would this jettison escape system have work in a accident similar to Space Shuttle Challenger, where the the explosion occurred while the command vehicle was still attached to booster..ie not jettison first?

Challenger didn't explode. It broke up when the SRB separated from the ET, and what you saw was the fuel and oxidizer spreading out into the air. Challenger wasn't destroyed by an explosion. She was torn apart by aerodynamic stresses.

But in an explosion, the idea is that the SuperDracos have enough thrust to pull the capsule out of the explosion and on its way to deploying parachutes. The capsule will have to ride out the shockwave.
 
Jan 16, 2020
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What's the future for this capsule? Refurbishment for another mission, the bone yard?
From what I have read, unlike Boeing capsules that are designed to land on terra firma and be reused, SpaceX astronaut capsules land in water and cannot be reused. So, they have to build an entirely new capsule for the next flight. I can't imagine how much that costs and why didn't SpaceX, known for reusability, skip this important point? They certainly have the technology and knowhow to land on land, they do it all the time. I read recently that Musk is talking about trying to capture astronaut capsules using their fast net equipped boats, as they have tried a number of times to grab satellite rocket fairings before they splashdown. Bold idea, but their track record needs improvement with very few captures on record. Sounds to me like an afterthought on Elon's part to preserve a used capsule for future reuse. Personally, why can't SpaceX modify their super Dragon capsule thrusters to ignite for that brief moment before touchdown on land?
 
Jan 23, 2020
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My father was the launch conductor for Gemini 6 and 7. He went on to be the test manager for the lunar module on Apollo 11 and Apollo 13. So, here’s his summary of the Space X abort- escape test... Great test to prove that the crew capsule can escape and land successfully if All engines shut down in flight. However, since the beginning of the Space Program (Mercury, Gemini, Apollo, Apollo/ Soyez, Shuttle) there has never been one incident when all engines just shut down in flight. Even if this was the scenario (for the first time) the test should have reflected a more worst case scenario. Yet, instead, Space X had the capsule jettison away several seconds ahead of a timed shutdown. This artificially gave the crew capsule a thousand plus yards of “head start” with an advanced velocity before the vehicle actually self destructed from aerodynamic forces. A true worst case ( but realistic scenario) would have been to activate the same abort-escape procedure not until the vehicle began to break apart ( therefore, rapidly burning “exploding” ).. So, in conclusion... A great test under simulated conditions that probably would not reflect a realistic situation. Let’s hope we never have to find out if the abort system works under more stressful conditions!
 
Nov 25, 2019
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From what I have read, unlike Boeing capsules that are designed to land on terra firma and be reused, SpaceX astronaut capsules land in water and cannot be reused. So, they have to build an entirely new capsule for the next flight. I can't imagine how much that costs and why didn't SpaceX, known for reusability, skip this important point?

They did not design for reuse because that would save NASA money but cost SpaceX more. This contract was awarded "fixed price" so anything that removes risk and cost makes more many for SpaceX. The ONLY customer for this is NASA so reuse is not in SpaceX's advantage.
 
Jan 23, 2020
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No. The shuttle was destroyed by aerodynamic force when one booster attachment point failed and caused the shuttle to yaw. The shuttle was not designed for air hitting from the side and broke up.

When you have an aircraft with a node and wings and tail it MUST be kept pointed "nose to the wind" or the structure fails.

When you have two solid boosters that are side by side there is nothing to do if one fails. The asymmetric thrust will break up the vehicle.

Back in the 70s Aerospace Corp. calculated that there would be a 2% failure rate for shuttles. This was the best estimate. NASA did not like the answer and buried the study. But it turned out to be about right. There is no good way to abort a shuttle launch. Only a few minutes of the launch is abortable for most minutes the result is "everyone dies". This is why they retired the shuttle. There was no possible fix and they would just have to cancel it or accept a 2% loss.
 
Jan 23, 2020
4
0
510
Visit site
No. The shuttle was destroyed by aerodynamic force when one booster attachment point failed and caused the shuttle to yaw. The shuttle was not designed for air hitting from the side and broke up.

When you have an aircraft with a node and wings and tail it MUST be kept pointed "nose to the wind" or the structure fails.

When you have two solid boosters that are side by side there is nothing to do if one fails. The asymmetric thrust will break up the vehicle.

Back in the 70s Aerospace Corp. calculated that there would be a 2% failure rate for shuttles. This was the best estimate. NASA did not like the answer and buried the study. But it turned out to be about right. There is no good way to abort a shuttle launch. Only a few minutes of the launch is abortable for most minutes the result is "everyone dies". This is why they retired the shuttle. There was no possible fix and they would just have to cancel it or accept a 2% loss.
Thanks, good info. Completely makes sense about the aerodynamic forces tearing it apart. Interesting data on the failure rate.
 
Jan 23, 2020
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Challenger didn't explode. It broke up when the SRB separated from the ET, and what you saw was the fuel and oxidizer spreading out into the air. Challenger wasn't destroyed by an explosion. She was torn apart by aerodynamic stresses.

But in an explosion, the idea is that the SuperDracos have enough thrust to pull the capsule out of the explosion and on its way to deploying parachutes. The capsule will have to ride out the shockwave.
This SuperDracos system is crazy cool. Good to see that the astronauts would have a fighting chance at survival in the worse case scenario of an anomoly.
 
May 2, 2020
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From what I have read, unlike Boeing capsules that are designed to land on terra firma and be reused, SpaceX astronaut capsules land in water and cannot be reused. So, they have to build an entirely new capsule for the next flight. I can't imagine how much that costs and why didn't SpaceX, known for reusability, skip this important point? They certainly have the technology and knowhow to land on land, they do it all the time. I read recently that Musk is talking about trying to capture astronaut capsules using their fast net equipped boats, as they have tried a number of times to grab satellite rocket fairings before they splashdown. Bold idea, but their track record needs improvement with very few captures on record. Sounds to me like an afterthought on Elon's part to preserve a used capsule for future reuse. Personally, why can't SpaceX modify their super Dragon capsule thrusters to ignite for that brief moment before touchdown on land?
The dragon is designed to be used up to 10 times no matter the recovery.
in the future, the dragon will land on land with the abort system. Only so much be done in stages, so the land system was put back to a later date.
The escape system is worthless in a launch explosion of the booster. It takes whole seconds to react, and seconds for the system to work. You only have a fraction of a second. It was designed to lift off a defective booster still in the tower, the Russians did that once, or if the booster had to be distorted in mid flight for whatever reason.
 

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