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SpaceX General Section / Re: F9 Block 5 Updates and Discussion
« Last post by Alexphysics on Today at 12:48 PM »
There's no reason to have more debate on that, it's solved now. From the GAO report:

Quote
To better understand the propellant loading procedures, the program and SpaceX agreed to demonstrate the loading process five times from the launch site in the
final crew configuration prior to the crewed flight test. The five events
include the uncrewed flight test and the in-flight abort test.
Therefore,
delays to those events would lead to delays to the agreed upon
demonstrations, which could in turn delay the crewed flight test and
certification milestone

As you can see, the in-flight abort will now be used as another test for the fuelling procedure in the final crew configuration, so it has to be an entire Falcon 9 Block 5 rocket. No more debate, no more rumors, just fact.
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SpaceX General Section / Re: F9 Block 5 Updates and Discussion
« Last post by glanmor05 on Today at 12:15 PM »
There's a lot of debate about that on the In-Flight Abort specific thread.  It seems like Core 1042 (Block 4) MIGHT do the job?

Nevertheless, my original question is answered.  Thanks again.
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SpaceX General Section / Re: F9 Block 5 Updates and Discussion
« Last post by Alexphysics on Today at 12:02 PM »
The in-flight abort will use a complete Block 5 rocket (first and second stages).
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SpaceX General Section / Re: F9 Block 5 Updates and Discussion
« Last post by glanmor05 on Today at 11:54 AM »
Thank you.  So next B5 flight (is the next flight) 08/22/18?

Only non-Block 5 flight planned thereafter is the in-flight abort test, so all being well the 7 flight thing won't come into play as regards delaying first crew flight?
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SpaceX General Section / Re: F9 Block 5 Updates and Discussion
« Last post by Star One on Today at 11:41 AM »
I have tried searching for this information, but can't find it (maybe on L2?).

My understanding is that SpaceX need to conduct 7 Block 5 flights (with no design changes) before being allowed to launch commercial crew?

I further understand that the initial flight of Block 5 didn't count because the new COPV design wasn't flown on that flight?

Which mission currently plans to use a core with the new configuration?  I assume each block 5 flight beyond that will fly the new tanks so there should be more than enough for this to become a limiting factor?

The next Block 5 flight will feature the new COPV design and count as the first of the seven.
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SpaceX General Section / Re: F9 Block 5 Updates and Discussion
« Last post by glanmor05 on Today at 11:32 AM »
I have tried searching for this information, but can't find it (maybe on L2?).

My understanding is that SpaceX need to conduct 7 Block 5 flights (with no design changes) before being allowed to launch commercial crew?

I further understand that the initial flight of Block 5 didn't count because the new COPV design wasn't flown on that flight?

Which mission currently plans to use a core with the new configuration?  I assume each block 5 flight beyond that will fly the new tanks so there should be more than enough for this to become a limiting factor?
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Excessive Water intrusion into the spacecraft on splashdown, to begin with...
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Both the Ground to Sat and the Sat to Ground link is a Spotbeam steered by the phased array. To communicate at all, (at least at any reasonable bandwidth) the ground-station needs to know both its own location and the current orbital parameters of all satellites it wants to communicate with. Each sat in turn needs to know its own orbital
location at any time and the location of each ground station it communicates with (and directs spot beams to)

Likely even the receiving link would need to know the angle from which the beam is incoming in order to demodulate and route the signal from a single source - through the phased array.

Not with centimeter accuracy, but within a few kilometers, more than enough to easily enforce license/region boundaries. If any country forbids SpaceX to operate within its borders it would be trivial to prevent their sats to steer their beams there, based on a zone-map, which would render any groundstations smuggled there inoperational.


The same is true if some country limits the availability of frequencies to a subset (or even superset) of the current FCC permit. SpaceX customers could still operate groundstations there but to be licensed they would have to limit themselves to the available frequencies. In turn the sats would have to limit themselves to the same for all spot-beams directed into that area.

Similar to how WIFI or GSM uses different channels in different parts of the world. In the US base stations need FCC license, in the EU they need a CE label, in China they need whatever authority is responsible for that. And the sats need to adhere to the same standard while overflying and communicating with equipment in that area with respect to used frequencies, max transmit power/field strength, and likely also regarding what data is transferred to where if the country in question imposes restrictions.

Just like the sats can easily be programmed to adhere to these restrictions, they could also be programmed to selectively ignore them. - I.e. allow mobile ground stations leased to the CIA to operate worldwide on a selective frequency band with guaranteed bandwidth. The tight spotbeams would make sure these transmissions wouldn't be easily intercepted/localized. Of course that would be in violation with local laws - but if a CIA spy in ****redacted**** wants to send their data back to HQ through an encrypted sat link, they won't bother to license and register their equipment with the local authorities - and if they are caught the unlicensed usage will be the least of their worries.

Most likely the CIA in particular would use existing dedicated government sats for that already up there, but who knows, sometimes maybe you need more bandwidth for some nifty videos ;) And SpaceX could offer similar premium contracts to other agencies around the globe that don't have the resources to operate their own sat network. Operating ground stations at their own risk.


That being said, OneWeb also uses PhasedArrays and spot beams and as such also knows where a ground station is and to which relay-station the link is being forwarded - even if its just a bent-pipe type of link, the beams are steered tightly. As such enforcing the sat to not relay data between endpoints in China and the relay in Japan would be just as easy - even though they are technically "in range" of the sat. Even with a bent pipe architecture, the sat can still choose which direction to forward the incoming data. And it can choose not to.


All in all the capability of inter-sat links doesn't make a big difference. The real question is if governments trust the sat operator to enforce the arbitrary gov restrictions they might impose - or not. That can include routing all traffic to a specific national ground-relay/firewall/intercept gateway. Whether inter-sat links are involved or not doesn't really change that.

In most cases SpaceX would likely profit more from compliance. Exceptions might exist for political reasons.
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Remember to stay on topic. Do so from this point onwards and we won't have to delete any posts.
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