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A SpaceX Falcon 9 rocket has exploded at Cape Canaveral

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Re: A SpaceX Falcon 9 rocket has exploded at Cape Canaveral

#201

Post by krschultz »

garyclarke27 wrote: post #194
artursapek wrote: post #51

Looks like they had a payload go with it. Sad. > "SpaceX confirm Amos-6 was aboard the Falcon 9 and was lost in the explosion." https://twitter.com/NASASpaceflight/status/77135388623807283...

How stupid, to test with satalite on-board?? esp considering how expensive they are, they should use a dummy the same size and weight. You can't test satalite functionality on the ground so a completly pointless risk to include it.

There are actually things to test in the integration between the rocket and satellite. It's not like the satellite is a dump piece of steel sitting on top of the rocket. The payload has its own computer, power systems, and propulsion. The interactions between that and the launching rocket / ground systems matter. Also mating the two is non-trivial, so you can push the static fire back closer to the launch if you are doing it with the payload on board.

A static fire without the payload on the rocket was already done in Texas several weeks ago. This is the final dress rehearsal before launch. I always thought of these tests as low risk, but I guess nothing in rocketry is low risk.

Re: A SpaceX Falcon 9 rocket has exploded at Cape Canaveral

#202

Post by akiselev »

jsprogrammer wrote: post #188
Phlarp wrote: post #125

Earlier quoted context omitted.

For more context, all (edit: American!) rockets for decades have had onboard self destruct systems and a "Range Safety Officer" on the ground whose entire job is to determine if and when to deploy this self destruct system. The cruise missile scenario is highly unlikely as the rocket itself would be destroyed soon after leaving its intended trajectory.

How often is the self-destruct mechanism tested?

Very often. Air Force range safety guidelines require a million dollar flight termination system and most of that cost is testing and quality control. I don't have an authoritative list of all flight terminations but it happens at least once every few years whenever a rocket fails to follow the set flight path.

Re: A SpaceX Falcon 9 rocket has exploded at Cape Canaveral

#203

Post by rayiner »

abduhl wrote: post #175
dogma1138 wrote: post #166

Earlier quoted context omitted.

It's a deal breaker most likely, the terms of the deal were based on AMOS-6 becoming operational by march 2017. There has been high level of criticism in Israel about the deal as many seen this as giving up it's sovereignty over its space platforms even tho under the deal the all operations of spacecom platforms would be still handled from Israel proper, I'm sure the r/conspiracies is already booming with sabotage th…

Sounds like SpaceX just killed multiple deals for this company. Could someone who knows about this kind of stuff (I assume this subset of the population is small) comment on whether there is recourse against SpaceX for losing the payload?

The risk of this happening was almost certainly accounted for in the contractual relationship.

Re: A SpaceX Falcon 9 rocket has exploded at Cape Canaveral

#204

Post by ProAm »

dogma1138 wrote: post #185
wyager wrote: post #174

Earlier quoted context omitted.

Won't they just relaunch in a few months? Not sure what the rebuild timeline is.

It takes years to build a satellite, the bus, and every component is purposely built each component and the satellite itself goes through months of testing and even if they could build one within 6 months all of the contracts would expire by then which will require Spacecom to open the bids again. All of the contracts were based on AMOS-6 being operational by a given date, AMOS-6 has been "under construction" for pro…

That's why you always build two.

Re: A SpaceX Falcon 9 rocket has exploded at Cape Canaveral

#205

Post by dandelany »

dogma1138 wrote: post #42
avian wrote: post #37

Earlier quoted context omitted.

I'm sure it's not like that. Pressure relief valves aren't exactly rocket science.

You can't vent rocket fuel, the kerosine will ignite from the expansion and the friction in the valve alone. Venting liquid oxygen is also a really really bad idea.

On the contrary, venting LOX is very common and easily visible in the lead-up to nearly every Falcon 9 launch. Google "falcon 9 lox vent" for plenty of videos/photos.

Re: A SpaceX Falcon 9 rocket has exploded at Cape Canaveral

#206

Post by rpazyaquian »

antisthenes wrote: post #162
skadamat wrote: post #146

Earlier quoted context omitted.

It's pretty well documented that people at SpaceX work 80+ hours a week consistently: https://www.quora.com/How-many-hours-a-week-does-a-typical-S... http://spacenews.com/op-ed-3-things-to-know-if-you-want-to-w... https://www.reddit.com/r/spacex/comments/25ixxq/is_spacex_wo...

Wouldn't be surprised if some overworked engineer made a mistake.

I agree. I bet that the 80+ hour work weeks are going to result in death someday.

Re: A SpaceX Falcon 9 rocket has exploded at Cape Canaveral

#207

Post by garyclarke27 »

krschultz wrote: post #201
garyclarke27 wrote: post #194

Earlier quoted context omitted.

How stupid, to test with satalite on-board?? esp considering how expensive they are, they should use a dummy the same size and weight. You can't test satalite functionality on the ground so a completly pointless risk to include it.

There are actually things to test in the integration between the rocket and satellite. It's not like the satellite is a dump piece of steel sitting on top of the rocket. The payload has its own computer, power systems, and propulsion. The interactions between that and the launching rocket / ground systems matter. Also mating the two is non-trivial, so you can push the static fire back closer to the launch if you are…

Would they do so if human cargo?

Re: A SpaceX Falcon 9 rocket has exploded at Cape Canaveral

#208

Post by dogma1138 »

monocasa wrote: post #198

That was my immediate thought too. Israel is known for playing rough when it comes to sovereignty concerns, particularly of a technological nature.

The Israeli government has approved the deal with China, if they didn't want it to go through they would have blocked it, their MOD has oversight on virtually all exports and international dealings.

Israel needed AMOS-6 more than anyone else because communication satellites are important for national security and are used by military and national defense agencies.

Even if somehow your crackpot theory had merit delaying the launch would have been an easier and cheaper way of tanking the deal than sabotaging a rocket.

This wasn't an Iranian spy satellite, Israel has no interests in hurting it national security, economy, and reputation by blowing their own shit up, I don't even understand why people would think they blew it up.

Re: A SpaceX Falcon 9 rocket has exploded at Cape Canaveral

#209

Post by jakub_h »

ProAm wrote: post #204
dogma1138 wrote: post #185

Earlier quoted context omitted.

It takes years to build a satellite, the bus, and every component is purposely built each component and the satellite itself goes through months of testing and even if they could build one within 6 months all of the contracts would expire by then which will require Spacecom to open the bids again. All of the contracts were based on AMOS-6 being operational by a given date, AMOS-6 has been "under construction" for pro…

That's why you always build two.

"That's why you always build two."

Unless you're a Raman. Then you'll build three.

Re: A SpaceX Falcon 9 rocket has exploded at Cape Canaveral

#210

Post by rattray »

dogma1138 wrote: post #208
monocasa wrote: post #198

That was my immediate thought too. Israel is known for playing rough when it comes to sovereignty concerns, particularly of a technological nature.

The Israeli government has approved the deal with China, if they didn't want it to go through they would have blocked it, their MOD has oversight on virtually all exports and international dealings. Israel needed AMOS-6 more than anyone else because communication satellites are important for national security and are used by military and national defense agencies. Even if somehow your crackpot theory had merit delayi…

> Even if somehow your crackpot theory had merit

We try to avoid that kind of tone here, regardless of the merits of anyone's comments.

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