SpaceX COTS Demo 1 Updates

[alexw]

Falcon 9 isn't really "EELV class", which is no criticism.

The most often flown Atlas V is the 401 config, Falcon 9 has basically the same payload capacity to GTO.
It might not be as scalable as the EELVs yet (no F9H) but I would certainly consider it in their class.

FWIW, I agree with Jim that the Falcon-9, in its current form, is a Delta-II-class launch vehicle.  The Raptor upper stage and possibly F-1e core derived LFB boosters might change that but that's off-topic for this thread.

    Why do you think so?

    With a 5m fairing, at 10mT to LEO (28.5 200km), 8.3mT to sun-synchronous (LEO 200km), 3-3.5mT to GTO (1500 m/s delta-V to go trajectory), Falcon 9 looks to slot in between Atlas V 501 and 511, often closer to 511.

    For Earth-escape orbits, naturally, Centaur pulls ahead.

    Delta II, Taurus II, and Soyuz...err.. 2, all seem to be in a lesser performance class.
   -Alex

[Ben the Space Brit]

Falcon 9 isn't really "EELV class", which is no criticism.

The most often flown Atlas V is the 401 config, Falcon 9 has basically the same payload capacity to GTO.
It might not be as scalable as the EELVs yet (no F9H) but I would certainly consider it in their class.

FWIW, I agree with Jim that the Falcon-9, in its current form, is a Delta-II-class launch vehicle.  The Raptor upper stage and possibly F-1e core derived LFB boosters might change that but that's off-topic for this thread.

    Why do you think so?

Because the Atlas-V-401 and -501 are being marketed by ULA as a direct replacement for the Delta-II.

[Robotbeat]

Isn't it true that EELVs were originally intended not to have solid strap-ons? So, certainly Falcon 9 is in the same class as the original spec for EELVs. Who knows where Falcon 9 will be in 8 years time.

This is a little pointless argument. Kind of like the HLV argument. It's better just to explicitly say what payload capacity you're talking about.

[ugordan]

Because the Atlas-V-401 and -501 are being marketed by ULA as a direct replacement for the Delta-II.

Say what? They may offer Atlas V 401 as a Delta II replacement, but only because it's the next cheapest LV they have. It's still substantially more powerful than a Delta II.

The thing with F9 is that its maxed-out performance roughly equals the basic EELV configurations. And that maxed out performance hasn't even been demonstrated yet. EELV only pick up from there. The next step for F9 is the Heavy.

I wouldn't call F9 "EELV class", although I wouldn't call it Delta II class, either. It fits somewhere in between, closer to Atlas V 401 than Delta II.

[Antares]

Isn't it true that EELVs were originally intended not to have solid strap-ons?

No, quite the opposite.  Solid strap-ons were always intended so that EELVs could be more closely matched to the payload mass.

PS: IMO, the F9 performance numbers don't yet pass my sanity check.  Parametrically, I think they're 10-15% too high.  Maybe they require the upgraded Merlin, which would make them more believable.

[Robotbeat]

Isn't it true that EELVs were originally intended not to have solid strap-ons?

No, quite the opposite.  Solid strap-ons were always intended so that EELVs could be more closely matched to the payload mass.

PS: IMO, the F9 performance numbers don't yet pass my sanity check.  Parametrically, I think they're 10-15% too high.  Maybe they require the upgraded Merlin, which would make them more believable.

Yeah, the Falcon 9 is not really humming along, yet.

But, I swear that I heard that at least one of the EELVs was not originally (when first proposed) supposed to have solid strap-ons.

[edkyle99]

Isn't it true that EELVs were originally intended not to have solid strap-ons?

No, quite the opposite.  Solid strap-ons were always intended so that EELVs could be more closely matched to the payload mass.

PS: IMO, the F9 performance numbers don't yet pass my sanity check.  Parametrically, I think they're 10-15% too high.  Maybe they require the upgraded Merlin, which would make them more believable.

The original designs for EELV did not have strap on solid motors.  Both Lockheed Martin and Boeing proposed use of different upper stages to cover different payload ranges.  Solids were added later, though designers may have contemplated their use from the outset.

Here's a look at the early EELV plans.
http://www.globalsecurity.org/space/library/report/1997/nov_ovrw.pdf

 - Ed Kyle

[ugordan]

PS: IMO, the F9 performance numbers don't yet pass my sanity check.  Parametrically, I think they're 10-15% too high.  Maybe they require the upgraded Merlin, which would make them more believable.

The numbers they float around now definitely assume Block 2 and have for some time, at least since the User Guide v1 was released back in 2008. One still wonders what other caveats those performance figures assume, though.

[Jim]

No, quite the opposite.  Solid strap-ons were always intended so that EELVs could be more closely matched to the payload mass.

Hate to correct you there.  Solids were added later in the program after commercial comsats were growing.  That is why the VIF has 1.X levels.

[Comga]

I apologize for making a simple remark that seems to have set off this F9 vs EELV discussion.  It really wasn't that important, and it was noted as OT at the time

[beancounter]

When will Jim revise his launch prediction? 

[butters]

When will Jim revise his launch prediction? 

It's still officially NET Nov 8, so even with a 1.5x time dilation to convert SpaceX time into standard time, there's still a high probability of a Nov launch date, especially since there's nothing else scheduled on the Eastern Range in mid-late Nov.

They have a static fire test that they want to do roughly one week before launch.  They may want to get that out of the way before the Shuttle launch on Nov 1 and the DIVH launch on Nov 4.  If they have to wait until after the range calms down, then Nov 8 may not be possible and the launch date may slip a week or so.

So I think that if we see a static fire by the end of this month, then Nov 8/9 looks good, but if not, then Nov 15-18 seems more likely.

But Jim may have a different and invariably more credible prediction...

[Lars_J]

A new spaceX update: http://www.spacex.com/updates.php

In it Elon mentions a planned 4 hr mission duration. So at least 2 orbits.

There's also this best shot yet of the Dragon, showing the heat shield: http://www.spacex.com/assets/img/20101001_dragonc1.jpg

There's also an internal shot of 'the second production Dragon spacecraft', showing some cargo racks and people: http://www.spacex.com/assets/img/20101001_scott.jpg (seems fairly roomy)

[Ben the Space Brit]

A new spaceX update: http://www.spacex.com/updates.php

...

There's also an internal shot of 'the second production Dragon spacecraft', showing some cargo racks and people: http://www.spacex.com/assets/img/20101001_scott.jpg (seems fairly roomy)

That would be the COTS-2 spacecraft, so it makes sense that it would be internally rigged like an operational CRS flight so that the flight dynamics match up to the real thing as much as possible.  As for the size, don't be fooled.  I suspect t hat we're looking from a camera flush up against the inner hull.  That will distort the perspective a little.

[corrodedNut]

Has this thing gotten bigger since Flight1? IIRC this was the source of the infamous "ice explosion" in pictures from the Flight1 static fire. Does anyone know or remember what it's for? 2nd stage telemetry? Perhaps improved for post-seperation tracking?

[Hauerg]

Has this thing gotten bigger since Flight1? IIRC this was the source of the infamous "ice explosion" in pictures from the Flight1 static fire. Does anyone know or remember what it's for? 2nd stage telemetry? Perhaps improved for post-seperation tracking?

Camera housing and live video downlink? So that they have an idea what happened if recovery of stage 1 fails again?

[ugordan]

It's an RP-1 tank relief vent.

[butters]

Also referring to the rear view shot of the first stage...

Did the first F9 have that clean flat expanse of white insulation(?) on aft surface of the thrust structure, with openings only for the throats of the engines and the turbopump exhausts? 

It looks really slick, and I don't remember seeing the first F9 looking so well dressed on her business end.  Is this a new attempt to achieve first stage recovery?  That would make sense, if it is indeed a modification for flight 2 and not just a part of the late integration steps that wasn't shown in the flight 1 update photos.

If they can recover the first stage this time around, in any reasonably intact condition, that would be a very impressive success for SpaceX.

[gospacex]

Also referring to the rear view shot of the first stage...

Did the first F9 have that clean flat expanse of white insulation(?) on aft surface of the thrust structure, with openings only for the throats of the engines and the turbopump exhausts? 

It looks really slick, and I don't remember seeing the first F9 looking so well dressed on her business end.  Is this a new attempt to achieve first stage recovery?  That would make sense, if it is indeed a modification for flight 2 and not just a part of the late integration steps that wasn't shown in the flight 1 update photos.

If they can recover the first stage this time around, in any reasonably intact condition, that would be a very impressive success for SpaceX.

Non-intact condition will be ok too. They can look at the wreck and figure out what gave up first, what didn't work as expected etc. Can't do that if the stage is 3 miles down in the ocean...

[Ben the Space Brit]

Non-intact condition will be ok too. They can look at the wreck and figure out what gave up first, what didn't work as expected etc. Can't do that if the stage is 3 miles down in the ocean...

That shouldn't be an issue, so long as the vehicle doesn't loose structural integrity.  The propellent tanks, once empty, should act as huge buoyancy tanks.