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SpaceX's Big Falcon Topic 2

SpaceChampion

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3 hours ago, Ghjhero said:

Is the launch going to be live streamed tomorrow?

Most definitely yes.

In a conference call with the press today Musk said if they wanted to do so they could attach 4 side boosters to the core booster, to make a Falcon Super Heavy.  Financially focusing on BFR makes more sense, but they have that option if it takes longer to make BFR than they expect.

Also sounds like they've decided against human-rating the Falcon Heavy to loft humans for now, so that Lunar fly-by Dragon flight they had booked by unidentified customers would probably be done with an early BFR flight in a few years instead.  BFR development is proceeding very well so far though.

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41 minutes ago, SpaceChampion said:

Most definitely yes.

In a conference call with the press today Musk said if they wanted to do so they could attach 4 side boosters to the core booster, to make a Falcon Super Heavy.  Financially focusing on BFR makes more sense, but they have that option if it takes longer to make BFR than they expect.

Also sounds like they've decided against human-rating the Falcon Heavy to loft humans for now, so that Lunar fly-by Dragon flight they had booked by unidentified customers would probably be done with an early BFR flight in a few years instead.  BFR development is proceeding very well so far though.

BFR is the what Musk is hoping to use to take colonists to Mars correct? How is it different from the Heavy?

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1 hour ago, Ghjhero said:

BFR is the what Musk is hoping to use to take colonists to Mars correct? How is it different from the Heavy?

Yes.  The upper stage of F-Heavy and F9 are not reusable.  There was talk about trying to upgrade them to make them so, but probably not worth the time and effort given their BFR plans.  F9/FH are both 3.7m in diameter at the upper stage, and this size limits the what you can send up anywhere to those dimensions.  The BFR is 9m in diameter, fully reusable two stage rocket with the upper stage capable of landing on Mars up to 150 tons.  FH could land about 50 tons on Mars with refuelling in Earth-orbit.  That's actually quite sufficient for an Apollo-style program to place feet on Mars, but not suitable for long term colonization campaign.  Full reusability means BFR will actually be cheaper than F9 or FH to launch.  BFR will also be an all methane rocket, instead of kerosene, so it can be refuelled from Martian resources (water + carbon dioxide turned into methane and oxygen).

 

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56 minutes ago, SpaceChampion said:

Yes.  The upper stage of F-Heavy and F9 are not reusable.  There was talk about trying to upgrade them to make them so, but probably not worth the time and effort given their BFR plans.  F9/FH are both 3.7m in diameter at the upper stage, and this size limits the what you can send up anywhere to those dimensions.  The BFR is 9m in diameter, fully reusable two stage rocket with the upper stage capable of landing on Mars up to 150 tons.  FH could land about 50 tons on Mars with refuelling in Earth-orbit.  That's actually quite sufficient for an Apollo-style program to place feet on Mars, but not suitable for long term colonization campaign.  Full reusability means BFR will actually be cheaper than F9 or FH to launch.  BFR will also be an all methane rocket, instead of kerosene, so it can be refuelled from Martian resources (water + carbon dioxide turned into methane and oxygen).

 

Thanks for the clarification. So as i understand it, the FH would be the transportation vessel for trips to Mars while the BFR is intended to be more spacious in order to accommodate the 100 or so colonists on each BFR. 

Is there any timeline for when the BFR would be test launched?

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38 minutes ago, Ghjhero said:

Thanks for the clarification. So as i understand it, the FH would be the transportation vessel for trips to Mars while the BFR is intended to be more spacious in order to accommodate the 100 or so colonists on each BFR. 

Is there any timeline for when the BFR would be test launched?

Falcon Heavy might only launch satellites, robots and rovers to Mars.  They could stick a Dragon capsule on it and qualify it for humans, but a Dragon is only capable of about about 7 days of life support.  Enough for a trip to the Moon and back.  Not enough for a Mars trip for humans, or even one human for 4 weeks or so is not long enough.  They'd have to design and build a transportation module with life support for many years.  Instead of doing that, they're going to replace Falcon + Dragon with BFR.  So the upper stage of BFR eliminates the need for a separate crew vehicle.  Dragon couldn't get off Mars to go back home anyway.

For a timeline, we can only know what SpaceX itself has said:  "SpaceX will begin full-scale construction of the first BFRs in the second quarter of 2018, with the aim to launch the first two BFR missions in the 2022 interplanetary alignment and launch window to Mars. Those two missions will then be followed by four BFR missions in 2024 to the red planet."

Long before that they have to test it, and gain experience flying it.  They're probably working on the 6-engine upper stage BFS (Big Falcon Spaceship) first before they build the 31-engine lower stage BFR (Big Falcon Rocket, sometimes called the Big Falcon Booster).  There could be test flights this year similar to their Grasshopper (Falcon 9 prototype) program, where they just launch a few hundred meters into the air and hover.

Then they have to test landing the BFR into the launch cradle.  The BFS has legs (for Mars) but the BFR does not.  It lands into a cradle that stays behind after launches.  The idea is to speed up turn-around time between launches so it lands on the launch pad / cradle, refuels and launches again.  This requires pinpoint accuracy with landings, which they have with Falcon 9 already.  This would have to be some time before 2020 I'd think.

Then full scale test of BFR (with BFS) to orbit, then later somewhere like the Moon.  2021?

These are all optimistic, the actual timeline is expected to be a bit longer.

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Yeah that timeframe is pretty optimistic, however even if things were to get pushed back a lot I think there’s a good shot we will have humans on Mars by the end of the next decade. I am happy to be able to watch the process unfold! Thanks again for the updates, your knowledge is very helpful!

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Here's a google map of SpaceX's launches showing the ground tracks of rockets and and positions of F9 and (today's) FH landings, if anyone is interested in seeing how far out in the the ocean the drone ships are when ship landings happen.  West coast launches fly southward to get into polar orbits for flights like the Iridium constellation. and East coast launches fly eastward for satellite launches and north-eastward for ISS missions.

The drone ship for Falcon Heavy's landing attempt of the core booster isn't as far out as I was expecting, it's actually around the distance as they go for some F9 flights.  But I'm sure that is because it is a demo flight and they're not burning all the fuel to get a heavy payload to geosynch transfer orbit.  The Tesla is pretty light after all.

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