Quote from: TomH on 09/22/2016 03:57 pmQuote from: Bynaus on 09/22/2016 05:31 am...A figure shown by a user on twitter showing essentially the BFR-boosted BFS flying to Mars, refueling there and flying back to Earth entry was commented by him to be the best representation of the MCT to date...Anyone have that image or a link to it? That's something I would like to see!I remember seeing this, was this it? It looks like Elon's comment about it being the closest guess he's seen so far is above the linked tweet and is actually about a diagram of a Hyperloop track. I don't see a reply from Elon about the MCT diagram.
Quote from: Bynaus on 09/22/2016 05:31 am...A figure shown by a user on twitter showing essentially the BFR-boosted BFS flying to Mars, refueling there and flying back to Earth entry was commented by him to be the best representation of the MCT to date...Anyone have that image or a link to it? That's something I would like to see!
...A figure shown by a user on twitter showing essentially the BFR-boosted BFS flying to Mars, refueling there and flying back to Earth entry was commented by him to be the best representation of the MCT to date...
Hi Everyone, this is a concept of a monolithic BFS: http://imgur.com/gallery/fGzkH
Quote from: BSenna on 09/23/2016 01:58 amQuote from: mfck on 09/23/2016 01:28 amQuote from: BSenna on 09/22/2016 11:23 pmNot specified, they look thin but ithis concept is more about the layout of the components and the general idea.Landing legs for such a rig would be a major component and the general idea (of anything spaceflight, let alone an ITS) would be to comply with laws of physics and waltz your design around the constraints they impose. Do you know why people find rockets beautiful?I've done this prevously, I thought a little about the system, but I simply didn't mind to put on the final renderings.Uh... it's better, but only marginally... I suggest you try to thoughtfully brake some things in your spare time. All kinds of things, of different materials, sizes and shapes. Also, try to be creative with how you apply the force needed to brake a thing - fast, slow, point, area, etc. While you are at it, remember that force has a vector and try to visualize it.
Quote from: mfck on 09/23/2016 01:28 amQuote from: BSenna on 09/22/2016 11:23 pmNot specified, they look thin but ithis concept is more about the layout of the components and the general idea.Landing legs for such a rig would be a major component and the general idea (of anything spaceflight, let alone an ITS) would be to comply with laws of physics and waltz your design around the constraints they impose. Do you know why people find rockets beautiful?I've done this prevously, I thought a little about the system, but I simply didn't mind to put on the final renderings.
Quote from: BSenna on 09/22/2016 11:23 pmNot specified, they look thin but ithis concept is more about the layout of the components and the general idea.Landing legs for such a rig would be a major component and the general idea (of anything spaceflight, let alone an ITS) would be to comply with laws of physics and waltz your design around the constraints they impose. Do you know why people find rockets beautiful?
Not specified, they look thin but ithis concept is more about the layout of the components and the general idea.
Quote from: BSenna on 09/22/2016 10:44 pmHi Everyone, this is a concept of a monolithic BFS: http://imgur.com/gallery/fGzkHNice one, wouldn't be surprised if the final thing looked a lot like this, but landing this thing vertically doesn't look practical. It's just a hunch, but I think it's gonna land horizontally, using a separate set of smaller engines. I don't think the MCT/ITS/whatever will have more than 2-3 Raptors and they will be used for orbital stuff, not landing. Oh, and deployable skids on the sides of the thermal shielding would be more robust than current F9 legs for the same mass. Well, only 4 days left until, hopefully, we know more.
While a horizontal lander would be better for cargo access, the MCT/ITS would need to launch from the surface of Mars, and there would be extra weight and complexity to support the loads of the vehicle landing on its side in addition to the loads generated by the main engine's thrust along the vehicle's longitudinal axis.
Its really puzzling. If you ask me I would think about a 20 years test programme with SEP, expandable disposable habitats, etc. But the rumour mill quasi-consensus point other way. On the Mars landing field, I agree, but other engines would add mass just for landing, and there is the coming back problem, the need to reorient the ship for take-off.
Quote from: BSenna on 09/23/2016 02:13 pmIts really puzzling. If you ask me I would think about a 20 years test programme with SEP, expandable disposable habitats, etc. But the rumour mill quasi-consensus point other way. On the Mars landing field, I agree, but other engines would add mass just for landing, and there is the coming back problem, the need to reorient the ship for take-off.Think of smallish engines in nacelles placed high on both sides of the ship. You could use the side engines for take off and fire the big ones (Raptors) high in the atmosphere. The mass argument is reasonable, but this alternative provides for a more flexible design. Also, smaller engines far from the ground would prevent damage from dust or rocks blasted off. Several small motors provide redundancy, so a single damaged engine would not risk the whole mission. Add a detachable nose and a ramp like some cargo planes or ferries and you get an easy to operate roll-on roll-of ship. Just a thought anyway.
Quote from: 2552 on 09/23/2016 12:34 amQuote from: TomH on 09/22/2016 03:57 pmQuote from: Bynaus on 09/22/2016 05:31 am...A figure shown by a user on twitter showing essentially the BFR-boosted BFS flying to Mars, refueling there and flying back to Earth entry was commented by him to be the best representation of the MCT to date...Anyone have that image or a link to it? That's something I would like to see!I remember seeing this, was this it? It looks like Elon's comment about it being the closest guess he's seen so far is above the linked tweet and is actually about a diagram of a Hyperloop track. I don't see a reply from Elon about the MCT diagram.That is definetly the image I was thinking of. but I can't find Elon's tweet/comment on it. Perhaps it was deleted. The best I can come up with is a blog entry repeating what the tweet said (including the picture): https://rocketry.wordpress.com/2013/07/15/spacex-f9-next-generation-booster-gets-full-duration-burn/"Pretty close to what I have in mind". So its not the Hyperloop tweet, although the content is similar.
Quote from: Bynaus on 09/23/2016 08:24 amQuote from: 2552 on 09/23/2016 12:34 amQuote from: TomH on 09/22/2016 03:57 pmQuote from: Bynaus on 09/22/2016 05:31 am...A figure shown by a user on twitter showing essentially the BFR-boosted BFS flying to Mars, refueling there and flying back to Earth entry was commented by him to be the best representation of the MCT to date...Anyone have that image or a link to it? That's something I would like to see!I remember seeing this, was this it? It looks like Elon's comment about it being the closest guess he's seen so far is above the linked tweet and is actually about a diagram of a Hyperloop track. I don't see a reply from Elon about the MCT diagram.That is definetly the image I was thinking of. but I can't find Elon's tweet/comment on it. Perhaps it was deleted. The best I can come up with is a blog entry repeating what the tweet said (including the picture): https://rocketry.wordpress.com/2013/07/15/spacex-f9-next-generation-booster-gets-full-duration-burn/"Pretty close to what I have in mind". So its not the Hyperloop tweet, although the content is similar.Maybe it actually was deleted, I just found this reddit comment that has a screenshot of John Gardi's MCT diagram and Elon's reply to it saying it's "pretty close to what I have in mind."Also, this Google+ post has a direct link to Elon's tweet, but the tweet doesn't exist anymore.
Quote from: 2552 on 09/23/2016 04:55 pmQuote from: Bynaus on 09/23/2016 08:24 amQuote from: 2552 on 09/23/2016 12:34 amQuote from: TomH on 09/22/2016 03:57 pmQuote from: Bynaus on 09/22/2016 05:31 am...A figure shown by a user on twitter showing essentially the BFR-boosted BFS flying to Mars, refueling there and flying back to Earth entry was commented by him to be the best representation of the MCT to date...Anyone have that image or a link to it? That's something I would like to see!I remember seeing this, was this it? It looks like Elon's comment about it being the closest guess he's seen so far is above the linked tweet and is actually about a diagram of a Hyperloop track. I don't see a reply from Elon about the MCT diagram.That is definetly the image I was thinking of. but I can't find Elon's tweet/comment on it. Perhaps it was deleted. The best I can come up with is a blog entry repeating what the tweet said (including the picture): https://rocketry.wordpress.com/2013/07/15/spacex-f9-next-generation-booster-gets-full-duration-burn/"Pretty close to what I have in mind". So its not the Hyperloop tweet, although the content is similar.Maybe it actually was deleted, I just found this reddit comment that has a screenshot of John Gardi's MCT diagram and Elon's reply to it saying it's "pretty close to what I have in mind."Also, this Google+ post has a direct link to Elon's tweet, but the tweet doesn't exist anymore.The overall idea behind that makes sense if the goal is simple reusability operations. However, "no refueling" in Earth orbit is not an option unless you want the second stage to require SSTO-like delta-v performance or have extremely low mass margins. There will probably be MCTs/ITSs acting as tankers in the plan.
Well, the "no refueling" part is actually the only point that is contradicted by something Elon said himself (that there will be re-fueling before departure). So its a safe bet that this point is (among others, perhaps) why he said "pretty close" and not "spot on".
I mean, if you do a densified liquid methalox rocket with on-orbit refueling, so like you load the spacecraft into orbit and then you send a whole bunch of refueling missions to fill up the tanks and you have the Mars colonial fleet - essentially - that gets built up during the time between Earth-Mars synchronizations, which occur every 26 months, then the fleet all departs at the optimal transfer point.
Of course is science fiction. I took more time on these first concepts, before the "put the entire thing on the surface of mars" rumour, I guess.
1) a2) 9-12 engines3) 8.5-10 m diameter4) 5)c) BFS contains smaller 'ejection pod' where humans reside during launch6) 7) a)direct entry 8.) c) All chemical for now, but plans to incorporate SEP down the roadI hope it will be called Bender
Well, this didn't get the traction that I'd hoped, but I'm still wondering if anyone would like to 'put their money where their mouth is' and declare their positions on the (hopefully) upcoming reveal details. Only a few days left! I'll start with my guesses:1-a, 2-31, 3-15m, 4-17.5Mlbs, 5a, 6a, 7a, 8cQuote1) Overall Launch Architecture a) MCT is composed simply of a BFR 1st stage and BFS 2nd stage/spacecraft (only) b) Boost phase consists of 2 stages, which put the BFS into orbit c) Other: 3rd stage, 'half' stages, drop tanks, etc. a) MCT is composed simply of a BFR 1st stage and BFS 2nd stage/spacecraft (only)Quote2) Number of Raptor Engines on BFR (1st stage)27 engines. Quote3) Diameter of BFR (1st stage)15-20 meters Quote4) Total Raptor 1st stage thrust (sl)Don't know. Quote5) LAS Architecture a) No LAS - BFS is the escape mechanism b) Traditional LAS - above BFS and is nominally jettisoned during launch phase c) BFS contains smaller 'ejection pod' where humans reside during launch d) Other, non-traditional LAS design d) Other, non-traditional LAS designQuote6) Shape and Landing Mode of BFS a) Capsule (perhaps elongated), w/ TPS on base b) Cylindrical or biconic - horizontal landing c) Cylindrical or biconic - vertical landing d) OtherCapsule, will probably be a human rated Red Dragon. Quote7) Mars and Earth return a) BFS does direct entry into Mars and Earth atmosphere b) BFS does orbital capture before performing entry burn and landing c) Same as b, but upon Earth return, stays in orbit for next synod c) Same as b, but upon Earth return, stays in orbit for next synodQuote Use of non-chemical thrust a) Not part of the plan b) Will use SEP for some/all of the big transits c) All chemical for now, but plans to incorporate SEP down the road C, all chemical for now, but will probably look into electrical engines once the technology has developed.
1) Overall Launch Architecture a) MCT is composed simply of a BFR 1st stage and BFS 2nd stage/spacecraft (only) b) Boost phase consists of 2 stages, which put the BFS into orbit c) Other: 3rd stage, 'half' stages, drop tanks, etc.
2) Number of Raptor Engines on BFR (1st stage)
3) Diameter of BFR (1st stage)
4) Total Raptor 1st stage thrust (sl)
5) LAS Architecture a) No LAS - BFS is the escape mechanism b) Traditional LAS - above BFS and is nominally jettisoned during launch phase c) BFS contains smaller 'ejection pod' where humans reside during launch d) Other, non-traditional LAS design
6) Shape and Landing Mode of BFS a) Capsule (perhaps elongated), w/ TPS on base b) Cylindrical or biconic - horizontal landing c) Cylindrical or biconic - vertical landing d) Other
7) Mars and Earth return a) BFS does direct entry into Mars and Earth atmosphere b) BFS does orbital capture before performing entry burn and landing c) Same as b, but upon Earth return, stays in orbit for next synod
Use of non-chemical thrust a) Not part of the plan b) Will use SEP for some/all of the big transits c) All chemical for now, but plans to incorporate SEP down the road