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The plume from new stubby bell on 2nd stage doesn't have greenish tinge that I normally see.  Could the green tinge have been from aft portion of longer bell getting too hot?  Iconel has copper iirc. Stubby seems much cooler given duller flame color in general

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34 minutes ago, darthgently said:

The plume from new stubby bell on 2nd stage doesn't have greenish tinge that I normally see.  Could the green tinge have been from aft portion of longer bell getting too hot?  Iconel has copper iirc. Stubby seems much cooler given duller flame color in general

Does Mvac use film cooling? Sorta looks like it.

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6 minutes ago, AckSed said:

Frigging hell that is a sine-wave of launches and landings. How much upmass is that now?

239 launches according to the video

Wiki: 17.4 t (38,000 lb) when landing on ASDS

So 4158.6 tons max if they were all F9 drone landings, but there were also some heavies and plenty of launches below max capacity, so no idea on the actual total, but that seems like a reasonable ball-park.

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The idea of having a 4+ deep queue production line of evolving prototypes of >Saturn V sized rockets is mind boggling compared to industry norms.  Consider that when New Glenn makes its first flight I wonder if it might be the only one, or maybe one of two, prototypes.  SpaceX is not just making rockets fungible, rather than precious, unique, and rare, via F9, it is doing similar with Starship+booster prototypes.  This is the way

Edited by darthgently
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3 hours ago, darthgently said:

SpaceX is not just making rockets fungible, rather than precious, unique, and rare, via F9, it is doing similar with Starship+booster prototypes. 

The building requirements really help. Steel welded in open air rather than finely machined aluminum ala Atlas 5 or Vulcan. Or even if they had stuck with thier earlier plan of carbon fiber bodies. Would we have seen this kind of cadence if every piece was being rolled on a huge machine in California? 

Somehow I doubt it.

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On 6/12/2023 at 8:56 PM, tater said:
On 6/12/2023 at 8:21 PM, darthgently said:

The plume from new stubby bell on 2nd stage doesn't have greenish tinge that I normally see.  Could the green tinge have been from aft portion of longer bell getting too hot?  Iconel has copper iirc. Stubby seems much cooler given duller flame color in general

Does Mvac use film cooling? Sorta looks like it.

The sea level Merlin 1D dumps the gas generator exhaust overboard, but the MVac delivers the gas generator exhaust into the downstream portion of the nozzle. The purpose here isn't really film cooling so much as it is squeezing a little extra Isp out of the engine by increasing mass flow through the end of the nozzle (just like the original F-1 engines did), but it does do a little film cooling, and that's why it looks the way it does.

To @darthgently's question: I believe that SpaceX switched the nozzle extension material from a metal alloy to  carbon-carbon some time around 2019 but I could be wrong. If it's RCC, any green tinge would not be from copper. The initial green tinge comes from the use of TEA-TEB for starts and restarts, but that usually fades quickly. It might just be a camera artifact.

On 6/13/2023 at 9:14 AM, darthgently said:

That 2nd tweet really drives it home.  We are well into a new era

Amazing.

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On 6/13/2023 at 9:47 AM, Terwin said:

239 launches according to the video

Wiki: 17.4 t (38,000 lb) when landing on ASDS

So 4158.6 tons max if they were all F9 drone landings, but there were also some heavies and plenty of launches below max capacity, so no idea on the actual total, but that seems like a reasonable ball-park.

From 2010 through 2019, Falcon 9 and Falcon Heavy launched 428.3 tonnes to orbit, not including the Zuma launch or the NROL-76 (although both of those were RTLS, so fairly low total mass). From 2019 through 2022, Falcon 9 and Falcon Heavy launched 1,251.1 tonnes to orbit, not including a number of classified NROL launches or Transporter-2 through Transporter-5.

So far this year, SpaceX has sent 434.0 tonnes to orbit using forty launches and is on track for a total of 100 total launches. So the total mass SpaceX has put in orbit is somewhere slightly above 2,114 tonnes. Keep in mind that many of these launches went below LEO, so they had lower gross mass but much higher energy.

With a current capacity of 100 Falcon 9 launches per year and a per-launch demonstrated max payload of 17.6 tonnes with RTLS, SpaceX can put 1,7600 tonnes into LEO annually.

21 minutes ago, Superluminal Gremlin said:

What the SR-71 used?

Yep. Also what the F-1 engine used, what Rocketlab uses for its Rutherford engine, and what Firefly Aerospace uses to ignite its Reaver engine. Its application is more common with rocket engines than jet engines, actually. The JP-7 fuel used for the SR-71 is notoriously difficult to ignite, so that's why they skipped a conventional ignition plug system and went with TEA-TEB.

The SR-71 could refuel in-flight so its persistence was typically limited by how much TEA-TEB it could carry and how many times it fired its afterburners. 

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The 2 ships are gonna be very important cuz of Artemis 3&4, these ships will perform the orbital refuelling test and like sn25 being a copy of sn24, sn27 is a backup copy for ship 26. With ship 28 and  ship 26 the test will go to test orbital refuelling.

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