kerbiloid

Hologram world.

Do not not do what you should do.

4d world. The ball is a 4d ball.

Starship payload is less than hundred tonnes.

Gravity prevents the throwing.

They found a minefield. Tourists on Minmus.

0.8 .. 1.1, and Starship is two-staged, so more 1.1 than 0.5. On their official site 1.1. *** Okay, let's calculate again (skipping the intermediate explanations, as they stay same). Booster thrust = 33 * 230 = 7 590 tf. T/W = 1.5 Total launch mass = 7590 / 1.5 ~= 5 060 t. Starship: Thrust = 9 * 230 = 2 070 tf. T/W = 1..1.1 Starship total mass = 2 070 / (1 .. 1.1) ~= 1 900 .. 2 100 t. Booster total mass = 5 060 - (1 900 .. 2 100) = 2 960 .. 3 160 t. Let's take the booster = 3 380 t from the example, it looks reasonable. So, Starship total mass = 5 060 - 3 380 = 1 680 t. T/W = 2 070 / / 1 680 ~= 1.23, a little great for the upper stage, but let's have in mind the 6 instead of 9 on the intermediate version. *** Booster operational fuel: 3 000 t, ISP = 340 s. Booster delta-V = 340 * 9.8 * ln(5 060 / (5 060 - 3 000)) ~= 3 000 m/s, of 9 600 required (or 9 000 from the example). *** Starship: Total mass = 1 680 t. Required delta-V = 6 600 (or 6 000) m/s, ISP = 370 s. Mass ratio = exp(6 600 (or 6 000) / (370 * 9.8)) = 6.2 (or 5.2). Final mass = 1680 / (6.2 or 5.2) = 270 or 320 t. Operational fuel mass = 1 680 - 270 or 320 = 1410 or 1 360 t. Tank + engines mass (from booster) = (1410 or 1 360 t) / 14.5 ~= 97 or 94 t. So, the garage + avionics + heat protection + cargo = 1 680 - (1410 + 97 or 1 360 + 94) = 1 680 - (1507 or 1454) = 173 or 226 t. Shuttle: total = 105 overloaded - 30 + 15 = 90 t. cabin ~ 10 t. booster engines ~10 t. cargo = 15 t. So, garage + avionics + heat protection = 90 -10 -10 -15 ~= 55 t. Payload = 15 t (landable in case of emergency) or 30 (if Shuttle is lost) + 10 t of cabin + 10 t of engines = 35 .. 50 t. So, full payload to total "what to land" mass ~= (35..50:55) = 0.6..0.9. Starship doesn't have a LES, and is declared human-rated, and has no "hard landing option" due to no gears, It either lands together with human cabin, or crashes. In Starship the landing mass is up to = 173 or 226 t, including ~95 t of tanks and engines (see above). Garage + avionics + heatshield + payload = (173 or 226) - 95 = 78 or 131 t. They can't return it without garage, avionics, and heatshield, as they are parts of the Starship, Payload / (garage, avionics, and heatshield) in Shuttle = 0.6 .. 0.9. So, 0.9 Payload = 70 or 118 t. So, if magically reduce the delta-V loss from 9.6 km/s to 9.0 km/s, it can take 118 t max. If take 9.6 km/s the reusable Starship payload is ~ 70 t. As original sixpack of the Raptors provides 2/3 of full thrust, so delta-V loss is greater, the 6 Raptor-2 version may have ~60 payload. *** (All of that is under assumption that 33 Raptors hadn't get into resonance and explode, and Starship had revamped into proper shape with proper heatshield, and that the thin and bulky tanks of Starship hadn't crashed.) Actually, 75% of that in best case. Read the calculation, updated after the @RealKerbal3x's notes.

230? Wiki says 185. Thrust ~185 tf (1.81 MN; 410,000 lbf) for Raptor 1 25% of difference. According to wiki, 185 * 33 / 1.5 ~= 4 000 t. +/- 1000 t? Well, let's go with 5 000 t. (It would be nice of course, if he was decoding the abbreviations. It this case I would not need to recalculate "mf" as "m final" instead of "m fuel"). fuel : empty 3000 + 380 - 220 : 220 ~= 14. Looks reasonable bor a booster, let's take it. I honestly have no idea what does this techobubble mean at all, and why should be care about angles, when the author just said: (Actually, 9.6, but who cares). All angles are already included. This 9..9.6 km/s presumes the optimal angle. The vertical-schmertical is a nonsense, the rocket is just moving by the optimal trajectory with nearly zero AoA and spending the energy against gravity and air drag. All we need to know is So, we need the Starship initial mass ratio: exp(6 000 / (370 * 9.8)) ~= 5.2 1620 /5.2 ~= 310 t. So, if take the same ration for landing (380 : 220), the empty mass of Starship is 150 / 380 * 220 = 86 t. The fuel mass = 1620 - 310 = 1310 t. The fuel:empty = 1310 : 86 ~= 15. So the aerobraking and deorbiting stage, with a reusable cargo bay, equipped with door mechanisms and so on, with command&control equip, with avionics, with heat protection, has greater fuel:dry mass ratio than the booster which reenters at an almost airplane 2 km/s speed? Seriously? Is the cargo bay, where they put the payload, massless or what? The winglets? The tyles? What do we have is a payload mass 160 t for a fully Starship's propulsion unit. I.e. exactly what I said about Saturn (140 t, expendable). Wait... But as the initial mass of Starship is 1620 t, it requires 1620 / 230 = 7 raptors But everywhere (in wiki, in video) it has just 3 raptors. So, T/W is < 0.5, and the whole underthrusted thing dives into ocean after having lost 1 km/s of delta-V. Kaboom! Splash-X !!! *** Let's recalculate. Thrust = 33 * 185 tf (according to wiki, rather than to the unknown source). Launch mass at T/W = 1.5 (from the given) = 33 * 185 / 1.5 = 4 070 t. Starship thrust = 3 * 185 tf. T/W (from the online calculator) ~= 1.1. Mass = 185*3/1.1 ~= 504 t. Let it be 600 t. (Starship + fuel + cargo), as the given T/W is ~1. Booster total mass = 4070 - 600 ~= 3470 t. Compared to the 3 380 t from forum, it almost same. Bingo. Buster fuel ratio: let's take the same = 3 470 / 3 380 * (3 380 - 220) ~= 3244 t. Operational = 3244 * (3 380 - 380) / (3 380 - 220) ~= 3 180 t. Booster delta-V ~= 340 * 9.8 * ln(4 070 / (4070 - 3 180)) ~= 5 065 m/s. A little much for a booster, but let's take it, as 5 000 - (9 600 - 7 800) of loss ~= 3 200 m/s of resulting speed. So, we need 4.6 km/s more from the upper stage. Total mass = 600 t. mass ratio = exp(4600 / (370 * 9.8)) ~= 3.55 Final mass = 600 / 3.55 ~= 170 t. Spent fuel = 600 - 170 = 430 t. Tank mass = 430 / 15 (see the booster) ~= 30 t. So, the garage + cargo = 170 - 30 = 140 t. Exactly Saturn V, but by 1 000 t heavier (because no hydrolox. And see: we didn't substract a heatshield and wings. If take the shuttle shape and mass ratio, a reusable stage would carry just 25% of the total mass as payload, so 140 / 4 ~= 35 t. *** So, we can conclude that the NSF post was using an overestimated Raptor thrust for booster, twice overestimated thrust for Starship, spent no mass on heatshield, avionics, wings, etc, and thus is a full nonsense is rersult. The realistic value is 140 t as fully expendable and ~50 t as reusable if the Boca-Chica shamans had improved the heat protection so much, otherwise 35. And see, we have treated the fuel tanks as steel-skinned and requiring no heat protection. Otherwise the reusable Starship is impossible at all (which is most probable). As the Soviets found out, 5 acoustic sources are better that 30+. Currently it's in only in PR. N-1 at least tried four times. Gas physics stays same.

Why did they start this at all, when smaller ones were easier to use?

Because the "barn" is a nuclear interaction cross-section unit, so what should he do there? What's better, cadmium or boron?

Makes umbrellas for robots.

Two energetical crysises later. Seriously. So, by 2050.

I forgot to add the mass of SpaceX mana which lets a 350 s ISP hydrocarbon + LOx rocket lift threetimes greater mass than earlier. What is "payload" and the "2nd stage"? That's why I would prefer a simple calculation here rather than magic Musk numbers.

Another weird thing from the close region. https://en.wikipedia.org/wiki/Black_Sea_deluge_hypothesis It's weird to think that the real origin of the neolythic and thus the modern civilisation can be on the toxic bottom of the Black Sea, and that those people were living in a paradise of that giant chalice and seeing the world from absolutely another pov. Btw, from there.

SHUTTLE pilot? Shuttle PILOT?

S-8 is not S-5. S-5 was 135 t always. The early SS/SH hype was about 500+ t to LEO. I compare a kerolox rocket to another kerolox rocket without SpaceX magic. ~[snip]~ (I guess, methalox is closer to the kerolox, rather than to the hydrolox, isn;t it?)

The Raptor thrust is ~180 tf. 30+ engines ~= 5 500 tf of thrust, i.e. ~4 500 t of total launch mass. The fuel is hydrocarbon, no hydrogen. So, the launch mass of SH+SS ~= 1.5 N1 launch mass (also hydrocarbon fuel) or ~1 UR-700 (hypergolic, with a little less ISP). This means payload of 140 .. 150 t to LEO. As the Raptors are definitely more effective than the old NK-33 or RD-270, let it be twice. Exactly 150+ t of total mass is what we have for the payload, plus 150 for the upperstage included. That's all. a 150 t reusable (if lucky) craft with 50 t of payload. They are juggling with payload mass since the project beginning. Originally it was 550. And they never made the mass distribution clear. Upd. The Shuttle cargo bay. 18 m long, 4.6x4.6 m wide. Cross-section area = 4.6 * 4.6 ~= 20 m2. Starship, a squared corridor in the cylindric hull: (9 / sqrt(2) )2 ~= 40 m2, twice as Shuttle. So at average cargo density it's twice as capable. On the published picture it's a little longer. Say, same 18 m (i.e. two diameters and not longer than a raiload car, because the cargo should be delivered by standard roads, cars, and trailers) 30 t * twice = 60 t. So, again we get the maximum payload value of 60 t. So, everything tells us that its cargo mass is ~55 t. *** If replace the cargo bay and the cabin with a shroud, its payload mass should be ~150 t, (But without Starship, only with its engines and tanks). *** So, SH/SS is 1.5 times heavier than Saturn with same payload, rather exotic landing tower, and rather doubtful chain of engines. Just a worse version of Saturn wannabe reusable.

How much in the bay? 150 t of reusable = dry mass = empty mass + cargo mass. As Starship is closer to a heatproof spaceplane rather than to a lightweight upper stage, it looks reasonable to take Shuttle as a reference. 105 t of dry mass (let's forget its small fuel tanks) = ~75 t of empty (60 t of the spaceplane itself + ~10 of the 2nd stage engines) + 30 t of cargo (overloaded) or 15 t of cargo (landable). So, as the Space Shuttle cargo mass is ~30/105 .. 15 / 90 = 0.25 of dry mass For Starship the cargo mass is ~150 * 0.25 ~= 40 t, i.e. two Protons or probably one Falcon Heavy. Let's add, say, 15 t of cabin, and it's ~55 t. 150 t of reusable can't carry 300 t in the bay. It's an expendable fairing + shroud. So, 300 should be the total Starship mass, including fuel.

300 tons is what? The Starship in total or what it can carry in a 9x10 m cargo bay?

It's like a 200+ mm APDS, it can hit a Landkreuzer. If attach it to an anti-tank railgun. 59 MJ per shot, 1 round per 5 seconds, 12 rpm. It could protect the reactor plant from a tank assault.

P.S. The boeingers think so, too.

Yes, and Saturn V was actually flying. So, probably you will hear this not once again before Starssip becomes new Saturn V three fourth of Saturn V, based on the payload mass.

These cutouts are "gulfs" with open coastline. The round(ed) holes inside (which are to lighten the construction or to screw something there, or to let the wires pass through) are "lakes", with close coastline. Both are stress concentrators, but the "lakes" weaken the structure less that the "gulfs" (like a pierced sheet of paper compared to a partially torn from one side if pull it apart). If this was by design, they could drill more holes, but unlikely make the ring thinner by the cutouts. Nobody attaches the nozzle to the hull. The support structure carries the combustion chamber with a short part of the nozzle, while the most part of the nozzle is attached to that. It was much easier to put 30 smaller engines on the Saturn-V 1st stage rather than develop F-1. But for reasons they preferred the headache of making a bigger engine.

The next episode of the series will probably be caused by the first stage engines still put too close to each other like in the first versions of the second stage.

On the first stage it tells that the required engine number was underestimated (possibly because the available engine thrust was overestimated, compared to the actual). Otherwise they would just make the pencil a meter wider, and needed no skirt (which is additional air drag). On the upper stage this in turn is forced by the lower stage diameter (and probably by the fires in almost every test caused by the engines put too close to each other), as no engineer in clear mind would make these cutout willingly. (Because they both weaken the constructon and complicate the production)