ULA launch and discussion thread

[Exoscientist]

 Not lying. Just puzzling. Why not just give give it 3 BE-4’s so can launch fully loaded without side boosters? With side boosters you then get even higher payload.

I used the payload estimator of Silverbirdastronautics.com to estimate a LEO payload of ~27 tons using 3 engines on the first stage w/o side boosters. This would beat the ~22 ton payload of the Falcon 9.

 BTW, it could then also do SSTO without the Centaur V upper stage. ;-)

   Robert Clark

Edited March 22, 2023 by Exoscientist

[tater]

2 hours ago, Exoscientist said:

 Not lying. Just puzzling. Why not just give give it 3 BE-4’s so can launch fully loaded without side boosters? With side boosters you then get even higher payload.

I used the payload estimator of Silverbirdastronautics.com to estimate a LEO payload of ~27 tons using 3 engines on the first stage w/o side boosters. This would beat the ~22 ton payload of the Falcon 9.

Engines cost money, and old space currently throws away engines. Not sure what the SRMs cost vs the ~$7M each the Be-4s cost. FWIW, when the ULA rocketbuilder site was around, each SRB apparently added ~$6.8M to the launch cost. That means they obviously pay less than that per SRM (cost on that calculator was retail).

 

2 hours ago, Exoscientist said:

 BTW, it could then also do SSTO without the Centaur V upper stage. ;-)

Aside from a gross reduction in payload, they'd also need to restart the Be-4s to deorbit the core (unsure the ULA version can do this).

Edited March 22, 2023 by tater

[mikegarrison]

3 hours ago, Exoscientist said:

Can Vulcan Centaur launch on just two BE-4 engines without side boosters?

 This Blue Origin page says Vulcan Centaur can get 10.8 tons payload to LEO on its two BE-4 engines without using side boosters:  

 But we can calculate the mass of the Vulcan booster to show its beyond that of the thrust of the two BE-4 engines.

Robert, I have noticed that you often use PD-type estimation tools and assume they are more correct than the numbers provided by the companies that actually have done all the detail design and manufacturing of the hardware in question. I suggest you might want to rethink the accuracy of that approach.

[Exoscientist]

“PD”?

 I use the numbers provided by the companies when provided. But some key numbers often are not provided such as stage dry masses, and often propellant masses. I asked Tory Bruno once about this and he said it was for competitive advantage.

 

  Bob  Clark

[tater]

22 minutes ago, Exoscientist said:

 I use the numbers provided by the companies when provided. But some key numbers often are not provided such as stage dry masses, and often propellant masses. I asked Tory Bruno once about this and he said it was for competitive advantage.

The bottom line is that ULA would not be offering a no-SRM Vulcan to customers—at reduced cost for reduced payload—without having done the numbers.

If it's in their user's guide, it works—they have the real numbers, we don't.

PS—this is ULA, not ARCA, they have done the math, and are legit.

[Kerballlistic07]

	GEO	GTO	LEO-REF	LEO-ISS	LEO-POLAR	MEO	TLI
0 Solids	N/A	3,500 kg 7,700 lbs	10,800 kg 23,800 lbs	9,200 kg 20,300 lbs	8,500 kg 18,700 lbs	N/A	2,300 kg 5,100 lbs
2 Solids	2,600 kg 5,700 lbs	8,400 kg 18,500 lbs	19,000 kg 41,900 lbs	16,300 kg 35,900 lbs	15,200 kg 33,500 lbs	3,900 kg 8,600 lbs	6,300 kg 13,900 lbs
4 Solids	4,900 kg 10,800 lbs	11,700 kg 25,800 lbs	24,600 kg 54,200 lbs	21,600 kg 47,600 lbs	20,000 kg 44,100 lbs	6,200 kg 13,700 lbs	9,200 kg 20,300 lbs
6 Solids	6,500 kg 14,300 lb	14,500 kg 32,000 lbs	27,200 kg 60,000 lbs	25,800 kg 56,900 lbs	23,900 kg 52,700 lbs	8,100 kg 17,900 lbs	11,500 kg 25,400 lbs
Upgrade	7,000 kg 15,400 lbs	15,300 kg 33,700 lbs	27,200 kg 60,000 lbs	26,900 kg 59,300 lbs	24,900 kg 54,900 lbs	8,600 kg 19,000 lbs	12,100 kg 26,700 lbs

Stole this from ULA's website. It would appear that performance would be comparable to Atlas V 401, with a slight upgrade.

1 hour ago, tater said:

PS—this is ULA, not ARCA, they have done the math, and are legit.

BTW this is amazing.

1 hour ago, Exoscientist said:

I asked Tory Bruno once about this and he said it was for competitive advantage.

BTWBTW This is also amazing that you know Tory!

[Exoscientist]

59 minutes ago, Kerballlistic07 said:

	GEO	GTO	LEO-REF	LEO-ISS	LEO-POLAR	MEO	TLI
0 Solids	N/A	3,500 kg 7,700 lbs	10,800 kg 23,800 lbs	9,200 kg 20,300 lbs	8,500 kg 18,700 lbs	N/A	2,300 kg 5,100 lbs
2 Solids	2,600 kg 5,700 lbs	8,400 kg 18,500 lbs	19,000 kg 41,900 lbs	16,300 kg 35,900 lbs	15,200 kg 33,500 lbs	3,900 kg 8,600 lbs	6,300 kg 13,900 lbs
4 Solids	4,900 kg 10,800 lbs	11,700 kg 25,800 lbs	24,600 kg 54,200 lbs	21,600 kg 47,600 lbs	20,000 kg 44,100 lbs	6,200 kg 13,700 lbs	9,200 kg 20,300 lbs
6 Solids	6,500 kg 14,300 lb	14,500 kg 32,000 lbs	27,200 kg 60,000 lbs	25,800 kg 56,900 lbs	23,900 kg 52,700 lbs	8,100 kg 17,900 lbs	11,500 kg 25,400 lbs
Upgrade	7,000 kg 15,400 lbs	15,300 kg 33,700 lbs	27,200 kg 60,000 lbs	26,900 kg 59,300 lbs	24,900 kg 54,900 lbs	8,600 kg 19,000 lbs	12,100 kg 26,700 lbs

Stole this from ULA's website. It would appear that performance would be comparable to Atlas V 401, with a slight upgrade.

BTW this is amazing.

BTWBTW This is also amazing that you know Tory!

 

  Not like I know him. I asked via his twitter account:

  Bob Clark

[tater]

Trying to figure out rocket specs to do calculations is fine, and we all have to guess until given accurate data by the manufacturer if we want to figure out interesting architectures using a given vehicle.

But when given actual performance data by the provider, you need to do your estimation using rocket calculators (or just math) using the known performance to anchor those calcs. So do your estimate for no SRMs, then change what you need to until you hit their numbers. 10,800kg to a LEO reference orbit. So plug in your dry mass numbers, and you get <0 payload to LEO. Start dropping propellant mass as a start and iterate until you get 10.8t. Maybe the dry mass is a little high. Maybe the BO stats on Be-4 are sandbagged?

[Kerballlistic07]

35 minutes ago, Exoscientist said:

Not like I know him. I asked via his twitter account:

I shouldn't have assumed haha 

9 minutes ago, tater said:

Maybe the BO stats on Be-4 are sandbagged?

Would NOT shock me at all!

2 hours ago, tater said:

If it's in their user's guide, it works—they have the real numbers, we don't.

Been snooping around ULA's website and I can't seem to find one as of now. Just the Rocket Rundowns, posters, and other information, but no official user's guide. Hope we see one soon! Love peering through those!

[Exoscientist]

19 hours ago, tater said:

Trying to figure out rocket specs to do calculations is fine, and we all have to guess until given accurate data by the manufacturer if we want to figure out interesting architectures using a given vehicle.

But when given actual performance data by the provider, you need to do your estimation using rocket calculators (or just math) using the known performance to anchor those calcs. So do your estimate for no SRMs, then change what you need to until you hit their numbers. 10,800kg to a LEO reference orbit. So plug in your dry mass numbers, and you get <0 payload to LEO. Start dropping propellant mass as a start and iterate until you get 10.8t. Maybe the dry mass is a little high. Maybe the BO stats on Be-4 are sandbagged?

 

 I  had estimated that  the Vulcan Centaur  given three BE-4's could get ~27 tons to LEO. But that was using a weight-optimized Vulcan dry mass estimate. However, I tried the SilverbirdAstronautics.com estimator on the Vulcan with the usual two BE-4's in the two side booster configuration and it gave results well above what was given on the ULA page on the Vulcan Centaur. So I think my dry mass estimate was too optimistic, i.e., too low.

 What I used was 25,000 kg for the Vulcan booster dry mass given three engines. The basis for that estimate is the weight-optimized Falcon 9 booster, using aluminum-lithium for the tanks, gets about a ~25 to 1 mass ratio. Then since methalox is at about 80% density of kerolox it should get about 20 to 1 mass ratio. This would give the Vulcan booster a dry mass of 25,000 kg.

 But that dry mass results in a badly overestimated V/C with two side boosters payload compared to that stated by ULA. So here's a another stab at a dry mass estimate. Make a comparison to the Atlas V booster mass ratio. This is hardly weight-optimized using just standard aluminum for the tanks as does the Vulcan stage. The Atlas V booster has a mass ratio of only 15 to 1.  Then the Vulcan with methalox at only 80% the density of keralox might get ~12 to 1 mass ratio. So the Vulcan dry mass might be as high as 45,000 kg. This results in a much closer Silverbirdastronautics.com payload estimate to the ULA numbers.

 

  Bob Clark

[tater]

From the Berger article on Dream Chaser, which is to be the second Vulcan certification flight.

Quote

The nominal plan for these certification launches entails flying Astrobotic's lunar lander on the "Cert. 1" mission in May, and Dream Chaser on "Cert. 2" in August. During a teleconference with reporters about one month ago, United Launch Alliance CEO Tory Bruno insisted that this schedule would allow Vulcan to become certified and fly its first national security mission "at the end of the year, out in quarter four."

Now Cert 2 (Dream Chaser) is NET December 17, 2023.

[sevenperforce]

On 3/22/2023 at 1:27 PM, Exoscientist said:

According to the heights given along the side of the image on the right, the bottom of the booster tank is at about 20 feet high, and its top at about 110 feet, for a length of 90 feet, 27.4 meters. The diameter is 5.4 meters, for a radius of 2.7 meters. Then the volume is π*2.7²*27.4 = 627.5 m³ . The density of methalox or methanolox at the mixture ratio of liquid O2 to CH4 of 3.6 is about 800 kg/m³. Then the mass of the propellant is 502,000 kg.  

 But the sea level thrust of the BE-4 engine is 550,000 pounds, so two is 1,100,000 pounds, i.e., 500 metric tons force. So two BE-4’s could not even loft the booster stage, let alone the upper stage and payload.

By my measurements of that image I'm getting a volume of 322.7cubic meters for the LOX tank and downcomer and a volume of 278.9 cubic meters for the LNG tank. Assuming non-densified propellant that gives 486 tonnes of propellant. But that's not accounting for ullage, etc., or launching with the possibility of slightly less propellant as @tater noted.

[RCgothic]

So Vulcan probably isn't launching H1:

 

 

[tater]

 

Quote

"A column of burning, clear hydrogen shot up into a mushroom cloud that dwarfed the test stand," one source said. "Their test article is definitely more than just 'damaged.'"

 

 

[FleshJeb]

This is why I'm taking the short odds on that tank farm next to Starship being an extraordinarily bad siting decision.

[tater]

 

[steve9728]

The "first launch curse":

knock knock*

[Meecrob]

Vulcan should do well, ULA is pretty good at not producing explosions.

[tater]

So Q3 earliest I guess.

[tater]

 

[tater]

 

[tater]

 

[Exoscientist]

 The “Angry Astronaut” gives a review of potential buyers of ULA and concludes Blue Origin would be the best match:

 He suggests keeping Tory Bruno to remain as head of ULA after the takeover. I agree Blue Origin would be a good match. A key reason is Blue Origin is committed to reusability for their launch vehicles. But  “Angry” notes their slow approach won’t work  when SpaceX is advancing so rapidly.  He feels Tory Bruno would promote a faster approach. I like Tory, but quite frankly he was only giving lip service to reusability at ULA. With the leadership at Blue Origin giving the directive that reusability has to be primary at ULA it might work.

  Bob Clark

 

[mikegarrison]

59 minutes ago, Exoscientist said:

 The “Angry Astronaut” gives a review of potential buyers of ULA and concludes Blue Origin would be the best match:

 He suggests keeping Tory Bruno to remain as head of ULA after the takeover. I agree Blue Origin would be a good match. A key reason is Blue Origin is committed to reusability for their launch vehicles. But  “Angry” notes their slow approach won’t work  when SpaceX is advancing so rapidly.  He feels Tory Bruno would promote a faster approach. I like Tory, but quite frankly he was only giving lip service to reusability at ULA. With the leadership at Blue Origin giving the directive that reusability has to be primary at ULA it might work.

  Bob Clark

 

Either I am confused or the guy in the video is confused. He says it would be horrible if ULA was sold to one of the "old space" companies -- but ULA *is* "old space". It's currently jointly owned by Boeing and Lockheed Martin, although at least one or both of those companies apparently want out, because it's up for sale.

[Exoscientist]

3 hours ago, mikegarrison said:

Either I am confused or the guy in the video is confused. He says it would be horrible if ULA was sold to one of the "old space" companies -- but ULA *is* "old space". It's currently jointly owned by Boeing and Lockheed Martin, although at least one or both of those companies apparently want out, because it's up for sale.

 Yes, I find that puzzling as well. If Blue Origin bought ULA does that mean it would own both the Atlas V and Delta IV and all their intellectual property?

  Bob Clark

Edited May 15, 2023 by Exoscientist