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FUS, Plus EUS, Plus ICPS? :huh:

That sounds even less plausible.

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17 minutes ago, RCgothic said:

FUS, Plus EUS, Plus ICPS? :huh:

That sounds even less plausible.

Yah know, sounds like those roclets i build in the first days of ksp. A rocket with 11 stages.

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48 minutes ago, RCgothic said:

FUS, Plus EUS, Plus ICPS? :huh:

That sounds even less plausible.

The rocket equation is a harsh master.

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EUS is never going on a FH. FH's maximum fairing size is 5.2m. EUS is 8.4m. 

ICPS would at least fit within the fairing. 

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Moved the April's fool to it's own thread, now that it and the following discussion have become too many and too off-topic.

 

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56 minutes ago, RCgothic said:

EUS is never going on a FH. FH's maximum fairing size is 5.2m. EUS is 8.4m. 

ICPS would at least fit within the fairing. 

This would require an custom fairing anyway because orion abort option. 

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Posted (edited)
2 hours ago, RCgothic said:

EUS is never going on a FH. FH's maximum fairing size is 5.2m. EUS is 8.4m. 

ICPS would at least fit within the fairing. 

That's what Wikipedia says, but it's got to be a typo. Orion is only 5m around, and the EUS is it's service module. None of the renderings I've seen have a massively outsized service module.

Edit:

File:Orion_Service_Module.jpg

Looks like 5.x meters to me.

Edited by Rakaydos

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There's a difference between a custom fairing to cover Orion and its LES at about 5m diameter at around Falcon's normal fairing size, and flaring out an interstage to cover EUS at 8.4m. The EUS is the same diameter as the SLS core.

The Orion service module (built by ESA) is narrower than Orion.

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EUS is full diameter (8.4m).

20160010361.Figure-1.SLS-Block-Developme

 

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1 minute ago, Flying dutchman said:

we have had a hopper test fire.

What? When? I don' t think anything happened last night and I don't think the window has opened yet today.

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1 hour ago, Rakaydos said:

That's what Wikipedia says, but it's got to be a typo. Orion is only 5m around, and the EUS is it's service module. None of the renderings I've seen have a massively outsized service module.

Edit:

File:Orion_Service_Module.jpg

Looks like 5.x meters to me.

The EUS is the exploration upper stage for SLS Block 1B which is intended to push both Orion+SM and any comanifested payload to TLI. The EUS is not Orion's SM.

Orion's SM is smaller than Orion, but Orion is still just over 5 meters. The internal envelope of a FH fairing is 4.7 meters. You cannot fit Orion on FH without a custom fairing.

If Orion+SM was launched on FH without ICPS, you could create a custom fairing that is the same diameter as the current version but truncates at the top of the service module, just as was done with EFT-1:

Spoiler

Orion-D4Hcutaway.jpg

DIV usually flies with a 5-meter fairing; here it was truncated into three sections enshrouding the (dummy) SM but terminating at the top of the SM. You would see the same custom adapter on Falcon Heavy.

This is possible because the SM will fit within the 4.7-meter internal envelope of the existing Falcon family fairing. However, the ICPS (which is literally a DCSS from the Delta IV family) is 5.2 meters and would not be able to fit inside this envelope. Either Falcon Heavy would need a new 5.5-meter fairing to wrap the ICPS + SM + Orion, or the entire upper stack from ET-1 would have to be dropped on top of a custom truncated 5-meter fairing stretching from the top of FHS2 to the base of the DCSS/ICPS's hydrogen tank.

Another significant issue raised by Bridenstine is the integration and erection of the FH in either configuration. FH is horizontally-integrated, rolled to the pad, erected, and then prop-loaded. However, Orion and the SM were intended to be vertically-integrated. Not only would that need to change, but they would also have to contend with a much more top-heavy FH, meaning the TEL might struggle to get it vertical.

9 minutes ago, Flying dutchman said:

we have had a hopper test fire.

I've seen detanking flares but no test fires yet...where are you getting this?

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Yeah, no hopper test fire yet as far as I can tell.

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5 hours ago, RCgothic said:

FUS, Plus EUS, Plus ICPS? :huh:

That sounds even less plausible.

Here's what could actually work, right now, with no modifications to anything other than software:

  1. Repeat EFT-1, leaving Orion and its fully-fueled ESM in an elliptical earth orbit.
  2. Launch a reused Dragon 2 on FHB5e into the same elliptical earth orbit; do not separate Dragon 2 from FHUS.
  3. Use Dragon 2's autonomous docking capabilities to mate Orion and Dragon 2. Software updates required for Dragon 2 to compensate for the added mass and altered CoM with the FHUS still attached.
  4. Use residuals in FHUS to push Crew Dragon + Orion + ESM into TLI.
  5. Orion and Crew Dragon separate after TLI. FHUS is ejected into heliocentric orbit; Crew Dragon completes a mid-course correction and performs a free-return; Orion performs DRO or NRHO injection for EM-1.
  6. Crew Dragon tests heat shield on entry from cislunar space.
  7. Orion performs cislunar mission, then burns EOI for completion.

No new vehicles, no new adapters, nothing. FH has same US configuration as in the Tesla test flight (modifications for extended restart).

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I may have mixed up the European Service Module and the Exploration Upper Stage.

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11 minutes ago, sevenperforce said:

Here's what could actually work, right now, with no modifications to anything other than software:

  1. Repeat EFT-1, leaving Orion and its fully-fueled ESM in an elliptical earth orbit.
  2. Launch a reused Dragon 2 on FHB5e into the same elliptical earth orbit; do not separate Dragon 2 from FHUS.
  3. Use Dragon 2's autonomous docking capabilities to mate Orion and Dragon 2. Software updates required for Dragon 2 to compensate for the added mass and altered CoM with the FHUS still attached.
  4. Use residuals in FHUS to push Crew Dragon + Orion + ESM into TLI.
  5. Orion and Crew Dragon separate after TLI. FHUS is ejected into heliocentric orbit; Crew Dragon completes a mid-course correction and performs a free-return; Orion performs DRO or NRHO injection for EM-1.
  6. Crew Dragon tests heat shield on entry from cislunar space.
  7. Orion performs cislunar mission, then burns EOI for completion.

No new vehicles, no new adapters, nothing. FH has same US configuration as in the Tesla test flight (modifications for extended restart).

I'm pretty sure that without added RCS on the Falcon second stage, that the spacecraft cannot translate sideways, as the RCS thrusters are all on one side of the COM. It can translate forward and backwards, but nothing else. Docking like that (especially without KSP's magic reaction wheels) would be really difficult, probably too difficult to be considered by NASA.

@Flying dutchman I believe that is the flare stack. If you look closely you can see the hopper to the left of it.

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7 minutes ago, Ultimate Steve said:

I'm pretty sure that without added RCS on the Falcon second stage, that the spacecraft cannot translate sideways, as the RCS thrusters are all on one side of the COM. It can translate forward and backwards, but nothing else. Docking like that (especially without KSP's magic reaction wheels) would be really difficult, probably too difficult to be considered by NASA.

Dragon 2 has 18 Draco thrusters. It can translate sideways while mated to the FHUS by using off-axis thrusters to compensate for pitch control. Software problem.

Would use more props than nominal docking, but again, totally doable. 

 

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That was burning off methane, not Raptor firing.

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11 minutes ago, sevenperforce said:

Dragon 2 has 18 Draco thrusters. It can translate sideways while mated to the FHUS by using off-axis thrusters to compensate for pitch control. Software problem.

 Would use more props than nominal docking, but again, totally doable. 

So cancelling the rotation wouldn't lead to a loss of translation because of the angles of off-axis thrusters? Can you explain that better to me? That doesn't seem like it should work in my head, but I may be wrong. 

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17 minutes ago, Ultimate Steve said:

So cancelling the rotation wouldn't lead to a loss of translation because of the angles of off-axis thrusters? Can you explain that better to me? That doesn't seem like it should work in my head, but I may be wrong. 

Like holding the end of a broom in 2 hands. You need to push down on the broomhandle at the end to keep it from falling out of your hands, but can lift closer to the middle to keep it in the air even though it's off balance. You spend more effort than if you were holding it in the middle.

in this analogy, the second stage is the broom, and different RCS thrusters are your hands.

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Right, I get it now. I had it earlier and commented to say so, but it looks like the forum ate my reply.

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Also Orion has full mobility. All Dragon needs to do is hold orientation, which is easy, even connected to a FUS.

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