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Besides, there is no guarantee that any launch company that is fed and nourished through these protections, will innovate and evolve beyond the constraints & expenses typically imposed by servicing these interests and remain a commercially viable/competitive entity. (if they ever were to begin with)
Indeed.
Arianespace has. ULA has not.
Quote from: rcoppola
But in the final analysis, I ask myself this question: What would it cost to design and build a reusable A6, a fleet of reusable capsules to put on top of it, then to launch and recover them 12 times? Would Arianespace have been able to compete with SpaceX's offer on that initial Commercial Cargo Contract, before they received the benefits of having done so in the first place? IMO...not a chance. And that's ok.
That's might generous of you. I guess it depends on what side of the boundary wall you sit, how much you trust that a countries access to space will remain "assured."
Quote from: rcoppola
2020 will see the board do a reset of sorts with Vulcan, New Glenn, A6 competing against a fully mature F9/FH Block 5. Let the games begin.
"Fully mature" that is until F9 block 6 is introduced. 
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SpaceX General Section / Re: Falcon-9 propellant feed system.
« Last post by speedevil on Today at 06:45 AM »

What could be the diameter of these openings....because these openings seem small for the flow rate of the propellant...or the feedlines dia increases afterwards??
The flowrate per engine is 270kg/s or so for both propellants.

Neglecting to properly measure things, it looks like the top guys hat width is about equal to the outside of the flange of the tubes on the tank,, call it 30cm, or 25cm internal.
20cm will lead to, with a flow of 270l/s a speed of ten meters a second or so.

Neglecting a bunch of stuff, and assuming it's water, and plugging it into the first pipe-flow calculator I find, I get ~1PSI pressure drop over 5m of pipe, with that diameter.
In other words, probably not enough to matter in a meaningful way.
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Suborbital Missions / Re: The suborbital thread!
« Last post by Lewis007 on Today at 06:45 AM »
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SpaceX General Section / Re: Wider fairing on top of F9/FH
« Last post by su27k on Today at 06:43 AM »
This is why a larger fairing is not needed.

They'll need longer fairing for EELV Category C payloads.
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Launch services compare better to taking buses instead of buying cars.
I presume you mean in the sense of a "ticket to ride" rather than an outright purchase of a transport vehicle?

Safety wise I think car crashes massively outnumber bus crashes in the US.
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I find it interesting that OneWeb is applying to license thousands of MEO satellites and gives no indication in their application that they would ever be deorbited.
Under the current orbital debris mitigation guidelines, OneWeb can leave them in the operational 8500 km circular orbit.  The guidelines say that disposal orbits should be above 2000 km, and stay at least 500 km away from 20200 km (12-hour orbit) and at least 500 km below or 300 km above 35800 km (GEO).

https://www.orbitaldebris.jsc.nasa.gov/library/usg_od_standard_practices.pdf

So, in other words, no de-orbiting at all.  >:(   (yes I know graveyard orbits are established practice and make a certain amount of sense for some orbits - but the sheer amount of satellites for this constellations should give people pause)
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Historical Spaceflight / Re: Good Apollo 11 Video
« Last post by catdlr on Today at 06:22 AM »
Bump.  I found an additional Apollo 11 launch video consisting of various black and white pad cameras and one color camera from the press area provided by an unknown network feed.

1969 Apollo 11 Saturn V launch, 1969 TV broadcast

Raw Space
Published on Jan 28, 2017

1969 TV broadcast of the launch of the Apollo 11 Saturn V rocket which carried astronauts Neil Armstrong, Buzz Aldrin, and Michael Collins to the Moon.  Armstrong and Aldrin landed the lunar module "Eagle" and became the first humans to set foot on another celestial body.  Collins piloted the command module "Columbia" in its orbit around the Moon.

https://www.youtube.com/watch?v=xdxzMPi19sU?t=001

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I just watched the first episode and it looks exciting so far.
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This is why a larger fairing is not needed.
That's the Curiosity rover, isn't it? Falcon Heavy is now not planned to go to Mars. Or at least that won't be its main role. It's a workhorse to deliver large payloads to GTO and the very few direct-to-GEO Air Force/Government missions.

How about Iridium-NEXT Flight 2:



That's reportedly a 9600 kg payload, 10 satellites weighing in at 860 kg each and a 1000 kg dispenser. Judging by eye, you wouldn't get another tier on top, due to the taper off the fairing. If other payloads are similar in density, you won't need to go much heavier before the volume becomes an issue.

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