Don't forget to save fuel for reuse.
You are not alone in getting such "not that big" results. Right now we're all over the map with possibly conflicting years old Elon statements and crazy big BFR/MCT rumors on Reddit. But the bottom line is that it does not even take the "mid sized" 15 million LB thrust vehicle to meet the LEO payload claims.Postponing the architecture announcement for the 3rd time indicates to me that everything is in a high state of flux. They've likely done some next level of detail of engineering analysis and arrived at some key numbers different than expected, which iterates revisions. With Musk the decisions will not be just space cadet tech driven but will also have a strong best economic model (as he best believes it) influencing size/capability tradeoffs.
BFR is much more than 100 tons to LEO. That much is clearly established.
Quote from: Robotbeat on 02/06/2016 12:57 amBFR is much more than 100 tons to LEO. That much is clearly established.The 100 tonnes figure was the useful payload landed on Mars IIRC. This is by a ship/lander that will refuel and depart sans 100 tonnes payload. The mass to LEO will vary considerably(though always be much larger than 100 tonnes) depending how refueling is incorporated and how you account for the spaceship itself.
Hello. I have a question, I know you had probably talk about this but I cant find it.What kind of propulsion will have second stage?
I'd also assumed RTLS in my past calculations but have come to believe that the 1st stage will instead land on a floating platform, as less propellant is needed with no boost-back.
Technical query for my BFS models.What's a rational target range for T/W of the 2nd stage at ignition taking into account gravity losses, etc.?I would expect it could be less than a 1st stage's preferred T/W.How low can it be at ignition?
The 2nd stage of this supposed TSTO has near but not equal to Earth SSTO performance and is a SSTO when departing Mars' surface.
Quote from: philw1776 on 02/06/2016 01:32 pmThe 2nd stage of this supposed TSTO has near but not equal to Earth SSTO performance and is a SSTO when departing Mars' surface.Can you clarify if you actually mean SSTLMO (to Low Mars Orbit) or SSTTEI (to trans-Earth-Injection). The latter is what everyone claiming integrated 2nd stage seems to be aiming for and it tends to yield a mars take off mass >1000 mt. The former is my position and involves SEP transit vehicles or refueling in mars orbit with SEP delivered propellants and keeps mars take-off mass to ~400 mt.
... How realistic is this?
...I read that novel too. But... Colonists are people. It will only take one going koo-koo to jeopardize everyone and the ship.
Quote from: JamesG123 on 02/05/2016 11:41 pm...I read that novel too. But... Colonists are people. It will only take one going koo-koo to jeopardize everyone and the ship. And if you catch the kook in time, you run a quick experiment to determine how long someone lasts outside the airlock.
I like the way he listed space tourism as something *other* companies are doing.. and he specifically mentioned orbital space tourism in that list. I'd love to know when SpaceX decided they were too good for this market.