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VeinPlumber t1_j1r18z8 wrote

Cause satellites can be insured and rebuilt if the launch fails, and launch escape systems add more complexity and cost to an operation (both the rocket and satellite).

People on the other hand, while they can be insured, it's the rebuilding part that we aren't so great at - hence launch escape systems for people, not satellites.

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LA_Dynamo t1_j1rcdqt wrote

Not just that, the satellites have to be built to withstand the additional g forces of an abort. This means more weight and complexity.

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[deleted] t1_j1r2ah8 wrote

[deleted]

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shardamakah t1_j1r3i3p wrote

Hey I’m a satellite launch insurance agent, I was wondering if your policy was up to date?

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[deleted] t1_j1r2mzr wrote

As well as the cost of replacing vs loss of life as u/VeinPlumber points out, I'm not sure of the stresses that occur when a launch escape system fires, but I imagine it is significant, like how ejecting from a jet puts extreme pressure on the pilot and often injures them. If that's the same with launch escape, then the technology in the spacecraft might not survive a launch escape or would be unusable afterwards. Satellites are designed to withstand certain pressures and temperatures for a certain amount of time during launch, while still ultimately functioning as intended. Add the wacky stresses of a launch escape and it would ruin whatever is in there, maybe. An engineer can correct me. But if so, cheaper and more straightforward to focus on successful launches than designing technology anticipating a failure.

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Dragonfly_Select t1_j1r6o14 wrote

Even if it survived, would you trust sending it back into orbit without taking it apart and putting it back together again?

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_d3vnull_ t1_j1r2jjr wrote

Just a few ideas: more complex to build, add costs, reduce the amount of payload and may even deny an target orbit depending on the launch vehicle.

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mcoombes314 t1_j1r0ywb wrote

What do you mean, like a launch escape system to salvage the payload if there's a failure early on in the flight, equipped with parachutes so that it can be retrieved?

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heartofdawn t1_j1r4r52 wrote

It's the tyranny of the rocket equation. The more mass you add, the more fuel you need to reach orbit. But that fuel also has mass, so you need even more fuel to lift the fuel you've just added, as well as bigger tanks- adding even more mass...

To maximize the amount of actually useful stuff in space (the satellites) you want to make the rocket as light as possible. Adding an ejection system would add significant mass as it would have to take the satellites, the payload adapter and the fairings, separate them from the rest of the rocket, parachute them back to Earth and then survive out in the ocean for several hours (most launches are over water to prevent you from hitting someone in cases like this) until they can be recovered.

And that's on top of the extra cost and complexity such as system would add. Since non-organic payloads can readily be rebuilt, it's just not worth it.

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Loa_Sandal t1_j1r51tj wrote

Satellites aren't expensive because of what they're made of. It's getting them into orbit that's the valuable part.

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Skyhawkson t1_j1r6cvm wrote

Satellites typically cost way more than their launch cost. The US Dept of Defense often flies billion dollar satellites on $150M launches

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roguetrick t1_j1r9nf9 wrote

What the hell are they doing? Funding a secret chip fab?

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shanlar t1_j1r2qb9 wrote

blue origin rockets do have a fail safe to eject the payload and self destruct the rocket.

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otatop t1_j1r4o4s wrote

All manned rockets have a launch escape system to protect the crew and all rockets have flight termination systems to destroy the rocket in case of failure.

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shanlar t1_j1r5y9c wrote

i am referring to unmanned rockets

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demanbmore t1_j1r2zs8 wrote

Those systems are possible, but they add weight and complexity to launch vehicles that strive to minimize weight and complexity. There's a cost to build and launch such a system, there's risk of failure of that system itself, and there's risk that that system could be the cause of catastrophic failure of the entire launch vehicle, especially if an ejection system uses any sort of explosive device to achieve ejection. Simply put, those who design and launch satellites have determined it is better to risk the loss of a satellite here and there than to try to reduce that risk with an ejection sytem.

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chriswaco t1_j1r4b25 wrote

Plus the satellite would have to be engineered to handle 6Gs of force compared to 3G in a normal flight, and it most likely would need to be waterproofed somehow.

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Alikont t1_j1r43ud wrote

Satellites are very fragile and complex enough already.

If you will also need to make satellite to survive sudden high horizontal acceleration of ejection system and not fail it will greatly complicate it.

Better to just insure/eat-the-loss and make another one.

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MaceKiller t1_j1r7swr wrote

Basically, the rocket is designed to withstand the extreme conditions of a launch, and the satellite is typically safest inside the rocket during this process. Adding an ejection system, which would allow the satellite to separate from the rocket in the event of an emergency, would increase the weight and complexity of the launch vehicle. This would also increase the cost of the launch and add additional risk to the process, as the timing and conditions for an ejection would need to be carefully planned and coordinated. Ultimately, the decision to include an ejection system on a rocket is a trade-off between these factors, and in many cases, it may not be worth the added expense and risk for a satellite launch.

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NerdyLumberjack04 t1_j1rce0y wrote

According to Stack Exchange, such systems have been proposed for nuclear reactors, because it would be a Very Bad Thing to leave it on a rocket on the verge of exploding.

Otherwise, the money and engineering effort it takes to build a launch escape system is simply better spent on making the original launch successful. Or just building a replacement satellite.

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its-octopeople t1_j1r51y4 wrote

Edit: I can't find any evidence to back up this claim. I don't think such a system has actually been used

I think some radioisotope-powered probes had something like that, in response to worries about a launch failure releasing radioactive materials into the atmosphere.

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AduroTri t1_j1r8y2p wrote

Because, it's a rocket we are dealing with. They are naturally explosive. When dealing with rockets and explosives. There is no "safe" option.

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TirayShell t1_j1r9ojo wrote

Math. Every little gram costs a lot of money to get into space.

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Grimsage777 t1_j1rcdwy wrote

Hardware is insurable and replaceable. Human life isn't.

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