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8 hours ago, tater said:

I was actually looking at the above F9/Crew Dragon image, and thinking about the relative size compared to Titan II GLV and came across this image (and noticed your name on it). The only edit I might suggest is to do Shuttle more like F9—cargo, and cargo plus the Orbiter in gray (the spacecraft are considered as part of the payload mass for the others). Looks like the heaviest Shuttle as launched (full) was 122,683 kg (Atlantis, STS-117). Would put the true capability of Shuttle in better context (else the others should have the crew vehicle excluded as well).

The only trouble is that then the Shuttle's payload is amped up by its 9.5 tonnes of engine that were decidedly NOT part of the payload in any meaningful way.

You almost want to have four different measures: payload (total mass to LEO including terminal stage), uncrewed cargo (amount of deliverable upmass to LEO without crew), crewed cargo (amount of deliverable upmass to LEO along with a crew vehicle), and crew capacity.

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Just now, sevenperforce said:

The only trouble is that then the Shuttle's payload is amped up by its 9.5 tonnes of engine that were decidedly NOT part of the payload in any meaningful way.

Yeah, I edited my most recent post after an espresso to add that SLS effectively drags the core (102t) to orbit—or could.

I even mentioned the engines, lol. So yeah, LEO calcs are non-trivial, it's never a great metric when all the vehicles are not all optimized for LEO.So you could do Shuttle minus engines, I suppose. 112t? Then of course there's the fact that SLS might be differently optimized for cargo to LEO if that was the goal.

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1 hour ago, tater said:

Yeah, I edited my most recent post after an espresso to add that SLS effectively drags the core (102t) to orbit—or could.

The Shuttle could have dragged the ET to orbit, too, though without any significant internal payload...and, indeed, there were suggestions of doing so in order to use the ETs as orbital habs. So "could" is not a great metric. F9's first stage "could" enter orbit as an SSTO.

1 hour ago, tater said:

I even mentioned the engines, lol. So yeah, LEO calcs are non-trivial, it's never a great metric when all the vehicles are not all optimized for LEO.So you could do Shuttle minus engines, I suppose. 112t? Then of course there's the fact that SLS might be differently optimized for cargo to LEO if that was the goal.

Let's see here:

Vehicle | Crew Vehicle | GLOW | Gross Mass to LEO | Cargo to LEO (uncrewed) | Cargo to LEO (crewed) | Crew Vehicle Mass | Crew Capacity

  • Atlas LV-3B
  • Titan II GLV
  • Saturn 1B
  • Saturn V
  • STS
  • Ares I
  • Falcon 9 Block 5
  • Atlas V N22
  • SLS Block 1
  • SLS Block 2
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Closer photos of SN4:

Worst damage seems to be to some sort of lagging on the test stand. SN4 itself doesn't seem too bothered structurally.

I think if there was serious damage it would be to Raptor20 from directed fire suppression. 

Also the flight readiness review is in progress:
Edited by RCgothic
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29 minutes ago, RCgothic said:

Closer photos of SN4:

Worst damage seems to be to some sort of lagging on the test stand. SN4 itself doesn't seem too bothered structurally.

I think if there was serious damage it would be to Raptor20 from directed fire suppression. 

Also the flight readiness review is in progress:

More probably damage to electronic because of fire suppression. Probably why they lost control and had to wait for boil out. 
You have the purely mechanical over-pressure valves then you have the computer operated systems who can vent faster. reducing the pressure in tanks. 

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9 minutes ago, magnemoe said:

More probably damage to electronic because of fire suppression. Probably why they lost control and had to wait for boil out. 
You have the purely mechanical over-pressure valves then you have the computer operated systems who can vent faster. reducing the pressure in tanks. 

Damage to electricals probably isn't that serious. Hoping Raptor 20 is still in good condition!

 

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22 hours ago, lolkekov said:

I don't understand a bit why they decided to send pensioners into space...

They might be already more familiar - one has flown as pilot twice, the other as mission specialist. The same way how they flew Apollo crews on STS-1.

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2 hours ago, tater said:

NHQ202005210007.jpg

Looks like I have good timing...

screenshot14.png
screenshot15.png
screenshot26.png

Spoiler

Doug and Robert aren't in the Crew Dragon; they're in the observation deck module on top of the crew access tower. Crew Dragon is integrated fully filled to save time, but Falcon 9 is unfilled and must be lifted to the vertical first, or the (Transporter)-Erector won't have enough juice to lift it. The Crew Access Arm is fully articulating and they walk down it and climb in before the vehicle is filled. 

Tanks are filled from the reservoir in the access tower. At T-2, the engines ignite; at T=0, the clamps release, the giant decoupler ring unlocks, the erector arms retract and pull back, and Falcon 9 lifts off.

At stage separation, the first-stage engines are shut down, RCS is activated, the upper stage is decoupled, and a pusher rod shoves the upper stage engine away. The upper stage has RCS on the Crew Dragon is not activated until it separates. There are no active reaction wheels on the vehicle (although they are activated in case of aborts to stabilize because we don't have differential thrust guidance on the SuperDracos).

It uses three-engine boostback, entry, and landing burns. Grid fins are fully functional and provide roll, pitch, and yaw authority. Landing legs deploy and lock into place and cannot be refolded.

After reaching orbit, Crew Dragon separates, activates its own RCS, and opens its nose cone using a powered hinge, exposing and activating the four primary Draco thrusters. They are automatically turned off when the nose cone is closed. Docking and undocking are straightforward. During re-entry, steering is accomplished by roll control only. A hatch pops off the base of Crew Dragon to expose the drogues, which are jettisoned with a decoupler when the mains pop.

100% stock.

Does anyone have a low-part-count stock ISS I can borrow?


 

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Just now, RealKerbal3x said:

@sevenperforce Lovely stock Dragon/F9! Did you make that for the NASA challenge, and how many parts is it?

Yes, I made it for the challenge though I won't be able to fly it unless I can scare up an ISS to send it to.

I used a lot of subassemblies so I am not sure of the final part count but I think it is probably somewhere around 1100. Maybe as low as 800. I wanted to use an actual crawler for the Falcon 9 as well as using a stock Tesla Model X to take Bob and Doug from the Astronaut Complex to the pad, but that was a bit too much.

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1 hour ago, YNM said:

They might be already more familiar - one has flown as pilot twice, the other as mission specialist. The same way how they flew Apollo crews on STS-1.

The most important thing is that the result is achieved :) I hope they chose the right people. Age is only a number :D

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36 minutes ago, CatastrophicFailure said:

@sevenperforce I’m curious to hear how you made that pusher work...

The decoupler is attached directly to the base of the upper-stage tank and translated down; it has zero-force decoupling and is autostrutted to the Crew Dragon for stability. Staged decoupling is off. The interstage (built from a fairing) is attached to the decoupler and translated up to hide it; its staging is also obviously off and it is autostrutted to the upper-stage tank. The engine assembly (it's actually 15 parts and has the same puffy, crinkly foil of the one we're used to) is surface-attached to the base of the upper-stage tank. A pusher rod with three struts is surface-attached to the interstage; it has a circular grip pad and a tiny-sized nose cone on the end.

I use an action group to decouple and extend the rod simultaneously, pushing the upper-stage engine free of the interstage. Then I spacebar to stage the engine.

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On 5/21/2020 at 12:14 AM, tater said:

 

Spoiler

9tHHXGwFbQxHheJscAw_TvId02OENHouZI5tQtE1

 

@jadebenn, this should be posted in a few threads, great image. I was actually looking at the above F9/Crew Dragon image, and thinking about the relative size compared to Titan II GLV and came across this image (and noticed your name on it). The only edit I might suggest is to do Shuttle more like F9—cargo, and cargo plus the Orbiter in gray (the spacecraft are considered as part of the payload mass for the others). Looks like the heaviest Shuttle as launched (full) was 122,683 kg (Atlantis, STS-117). Would put the true capability of Shuttle in better context (else the others should have the crew vehicle excluded as well).

EDIT: Coffee in me and I just posted something that @sevenperforce posted as well, right after I did—Shuttle engine mass probably not counted as payload for fair comparison, so that makes Shuttle closer to 112t (pretty close to SLS).

Here, I threw this together.

Human Launch Vehicle Liftoff Thrust Gross Mass to LEO Cargo to LEO (uncrewed) Comanifested Cargo Crew Vehicle Crew Vehicle Mass Crew Operation
Atlas LV-3B 1881 1360 0 0 Mercury 1400 1 1962-1963
Titan II GLV 1900 10201 7900 0 Gemini 3790 2 1965-1966
Saturn 1B 7100 31600 21000 0 Apollo CSM 14690 3 1968-1975
Saturn V 35000 153500 118000 16400 Apollo CSM 28800 3 1968-1972
STS 30250 114509 104000 24310 Orbiter 78000 7 1981-2011
Ares I 15000 41287 25400 0 Orion 26520 4 N/A
Falcon 9 B5 7607 27300 22800 6000 Dragon 2 15525 7 NET 2020
Atlas V N22 7204 15437 17211 0 Starliner 13000 7 NET 2020
SLS Block 1 39440 98490 95000 0 Orion 26520 4 NET 2021
SLS Block 1B 39440 115205 105000 11000 Orion 26520 4 NET 2025

Italicized values are theoretical/not-demonstrated. To get on the list, a vehicle must have been an orbital-class crewed launch vehicle that had at least one test launch from US soil. Operational period refers to actual crewed orbital flight, not launch vehicle activity generally. 

Edited by sevenperforce
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21 minutes ago, sevenperforce said:

Here, I threw this together.

Human Launch Vehicle Liftoff Thrust Gross Mass to LEO Cargo to LEO (uncrewed) Comanifested Cargo Crew Vehicle Crew Vehicle Mass Crew Operation
Atlas LV-3B 1881 1360 0 0 Mercury 1400 1 1962-1963
Titan II GLV 1900 10201 7900 0 Gemini 3790 2 1965-1966
Saturn 1B 7100 31600 21000 0 Apollo CSM 14690 3 1968-1975
Saturn V 35000 153500 77000 16400 Apollo CSM 28800 3 1968-1972
STS 30250 114509 104000 24310 Orbiter 78000 7 1981-2011
Ares I 15000 41287 25400 0 Orion 26520 4 N/A
Falcon 9 B5 7607 27300 22800 6000 Dragon 2 15525 7 NET 2020
Atlas V N22 7,204 15,437 17211 0 Starliner 13,000 7 NET 2020
SLS Block 1 39440 98490 95000 0 Orion 26520 4 NET 2021
SLS Block 1B 39440 115205 105000 11000 Orion 26520 4 NET 2025

Italicized values are theoretical/not-demonstrated. To get on the list, a vehicle must have been an orbital-class crewed launch vehicle that had at least one test launch from US soil. Operational period refers to actual crewed orbital flight, not launch vehicle activity generally. 

This is a bit confusing, I tough Saturn 5 was more than 100 ton to LEO, yes part of this was 3rd stage use for lunar injection burn, 3rd stage also did the circulation burn into LEO.
It also launched Skylab. 
Shuttle itself was not cargo although it was used as an short term space station for many missions but the dry mass for return should not count for it or starship. 

A bit hard to see the italic but assumes its Ares and SLS, both Falcon 9 and Atlas has many launches but none manned. 
Falcon 9 and Starliner bought states 7 crew even if it will only be used with 4, do they have an emergency 7 man capacity as in 3 spare seats probably so they can evacuate ISS on their own. 

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