Exoscientist

I was using “cost” and “price” interchangeably, which I shouldn’t have done. What I meant was price to the customer. Currently, that’s $67 million for the F9. So still going by the €40 million first order estimate for the price of two SRBS, resulting in an estimate of a €35 million price for the Ariane 6 without SRB’s, suggests a price for a 3 Vulcain Ariane 6 as €55 million, still less than the $67 million price for the F9. I’m betting that the production of the Ariane 5 cores can be restarted much more quickly and less costly, than if it were an entire new development from scratch. Again, that is one of those impertinent questions that someone, anyone in the European space community should ask. “Nolandung”, do you have a source for the 91 M€ for Ariane 64 and 74 M€ for the Ariane 62 price numbers? The higher price numbers I cited come from 2021. Robert Clark

Good you are using the Silverbird Astronautics estimator but it does have some quirks. First, it always takes the vacuum values for both thrust and Isp even for first stage engines because it already takes into account the diminution at sea level. Another key point is that you should set the inclination to match the latitude of the launch site to maximize payload. This is actually a fact of orbital mechanics. So after selecting the launch site as Kourou, French Guyana for the Ariane, set the launch inclination as 5.2 degrees to match that sites latitude. Also, you should probably set the “restartable upper stage” option as No, since this sometimes reduces payload when selected Yes, perhaps because it will keep some propellant on reserve for restart. Here we are finding the max expendable payload, so we’re not using a restart option. About using the larger Ariane 5 propellant tank for the 3 Vulcain version, once it is observed that this way you can match the Falcon 9 payload and at lower cost, it will become apparent that is the way to go. Bob Clark

F9 still has higher thrust than dry mass of booster even using only one engine. So F9 uses what SpaceX calls “hover-slam” where the thrust is precisely timed so that vehicle reaches 0 velocity just as it touches down. The same could work with the Vulcain throttled down on only one engine. Actually I don’t like “hover-slam”. Better: use two Vinci engines. They are only 160 kg each and would allow hovering landing. Bob Clark

For the higher thrust of three Vulcains you should use the higher propellant load of the Ariane 5. Even the later Ariane 5 “E” version at a larger 170 ton propellant load would work. To get a better estimate that takes into account lift off TWR use the Silverbird Astronautics payload estimator at https://www.silverbirdastronautics.com/LVperform.html Bob Clark

I get in the range of 20 tons to LEO by the rocket equation. I used the 158 ton propellant load of the original Ariane 5 “G” version. I bumped its dry mass to 14 tons for the 3rd Vulcain. I used a Centaur-like upper stage with an approx. 90% propellant fraction at 40 ton propellant mass at only 4 tons dry mass. I also assumed it had a high efficiency hydrolox vacuum engine matching the RL-10, as the Ariane 6 Vinci engines does, at 465 s vacuum Isp. Then the rocket equation gives a delta-v of: 434*9.81Ln(1 + 158/(14 + 44 +20)) + 465*9.81Ln(1 + 40/(4 + 20)) = 9,190 m/s, probably sufficient to orbit with a 20 ton payload. The rocket equation does not take into account takeoff TWR though so you need a more accurate payload estimator to say for sure. Bob Clark

Three Vulcains means it could loft higher mass so you could use a larger upper stage. Try it with a 40 ton propellant load hydrolox upper stage. Bob Clark

Thanks for that. The key question is how quickly that reusable system can be fielded. ArianeSpace has said already a reusable system won’t be fielded until the 2030’s. ULA was driven to the brink of bankruptcy by denying the importance or reusability, as did ArianeSpace also. It becomes extremely dubious that ArianeSpace can survive another decade by offering the non-reusable Ariane 6 at 2 to 3 times higher price than the reusable Falcon 9. By the way, in discussing above why the ESA member states producing the solid side boosters want to keep using solids in all ESA launchers I neglected to mention the most important reason: as I showed above the SRB’s make up the largest cost of the Ariane 6, more than the cost of the entire rest of the rocket. But that means by geo-return the companies in those countries making the SRB’s receive the greatest revenues and profit from the launches. The countries where these companies are located like this of course since it supports the space industries in those countries. But note it means the largest share of taxes also on those revenues and profits goes to those countries. About the lift off thrust issue, remember the greatest mass is coming from the solids. So the lift off thrust needed is much less when no solids are used. Now note the ISP of hydrolox is much higher than the solids, resulting in equal or higher payload to orbit. Bob Clark

Knowledgeable ESA observers have been aware for awhile now that the ESA policies for distributing funds and costs to the differing member states do not result in the most cost effective vehicles. It’s a policy called geographical-return that requires member states costs to be apportioned by some set proportion of the billion dollar development costs. So if some member states have been contributing some large proportion of the costs through solid side boosters, that cost continues to be part of the development for new rockets or upgrades. The governments of the member states regard this as a good thing because it helps to keep active, and paid, the space industries and space industry employees in their countries. But another key reason why some member states like the funds for the ESA to go to develop solid rocket side boosters is because those funds help also to develop solid rockets for their defense programs. So rather than those countries having to pay the entire cost of the solid rocket missiles in their defense programs on their own, some portion of that is actually paid for by the ESA in developing solid rocket side boosters for space launchers. You can see why there is a great incentive for those member states, which have great influence on the direction and funding choices for the ESA, to continue to want to use solid rocket side boosters in all launchers produced by the ESA. But the stunning fact is how much more expensive the solids are for the Ariane’s than just adding another Vulcain engine! As I mentioned above, the €75M cost of the two SRB version of the Ariane 6 compared to the €115M of the four SRB version, suggests, as a first order estimate, that we can take the cost of two SRB’s as €40M. But the cost of a single Vulcan is only €10 million! So the two SRB’s on the Ariane 6 base version costs 4 times more than an additional Vulcain! So, again as a first order estimate, we can take the cost of a two Vulcain Ariane 6 with no SRB’s as only €45 million, ~$50 million. This compares quite favorably to current $67 million cost of the Falcon 9. The reason why this isn’t done can not be attributed to some supposed multi-billion development cost to add an additional Vulcain to the Ariane core. Actually, it’s the current plan for the Ariane 6 with the newly developed solids, new upper stage, and new Vinci engine whose development cost is in the $10 billion range. It’s really quite stunning to realize the same could have been accomplished at only a ~$200 development cost simply by adding another Vulcain to the Ariane 5 core and using the same original cryogenic upper stage. Nearly a factor of 100 times cheaper! But nobody knows this because nobody asks that one simple question, “How much would it cost to add a second Vulcain to the Ariane 5/6?” Now, once you have the all-liquid Ariane 6 that costs even cheaper than the Falcon 9, you can also keep up with SpaceX in reducing price by reusability by also reusing the core stage via powered landing a la the F9 booster. Again, the solids in the current Ariane 6 version would not save on reusing them as the Space Shuttle program abundantly showed. So that huge €40 million cost just for the SRB’s on the Ariane 6(more than the cost of the entire rest of the rocket!) out of the total €75 million would be fixed no matter how many times you wanted to reuse the core. For the manned capable launcher, just use the all-liquid Ariane 6 since you no longer have the safety issues of using SRB’s on manned launchers. For the capabilities of the all-liquid Ariane 6, see here: Multi-Vulcain Ariane 6. https://exoscientist.blogspot.com/2018/02/multi-vulcain-ariane-6.html Bob Clark

Actually, they can. All it would take is someone, anyone in the European space community with the audacity to ask that one impertinent question, “How much would it cost to add a second Vulcain to the Ariane 5/6?” Once that question is asked, and answered, it becomes obvious how to proceed to match SpaceX in low cost, reusability, and manned launchers. Bob Clark

Perhaps because I’m a budding curmudgeon myself I like his “slaying the sacred cows” style. Even if he is a supporter of SpaceX he makes criticism of them if he feels they are taking a wrong approach. Much more honest, and realistic, than serving as their cheerleader on every topic. Bob Clark

Watch the video. He is a fan of SpaceX. He wants the SH/ST to be rapidly qualified for operational flight. That’s not going to happen when multiple engines RUD during test flights. Robert Clark

Thanks for that article. Ariane 6 not launching till 2024 puts it even further behind in trying to compete with the F9. Quite important also is to note this Ariane 6 will not be reusable. In fact another article said ESA will not field a reusable vehicle until the 2030’s. We’ve already seen ULA driven to the brink of bankruptcy by betting against reusability. There is little doubt the same will happen to ArianeSpace if they wait a decade to field a reusable vehicle. Astonishingly, the littlest babe could solve the problem of Europe having a reusable vehicle to compete with the F9 and at the same time provide Europe with a manned flight capable rocket. All that would be required is to ask the impertinent question, “How much would it cost to add a second Vulcain to the Ariane 5/6?” For then ArianeSpace forced to answer honestly would have to admit it could be done for only $200 million. Indeed this was found to be the case by JAXA when adding a second hydrolox engine to the H-II launcher for 27 billion yen, approx. $200 million. (See highlighted sentence below.) But then that’s the entire answer to the problem of both reusability and manned capable space vehicles! First of all if you want low cost reusability then you have to ditch the solids. The Space Shuttle program showed solids do not save on reuse. Quite important also is the fact an additional Vulcain costs less than the two solid rocket booster on either Ariane 5 or Ariane 6. To give an indication of how bad is the cost issue against the solids in comparison to just using an additional Vulcain, note the €75M cost of the two SRB version of the Ariane 6 compared to the €115 of the four SRB version. Then as a first order estimate, we can take the cost of the two SRB’s as €40M. But the cost of a single Vulcan is only €10 million! Then, again as a first order estimate, we can take the cost of a two Vulcain Ariane 6 with no SRB’s as only €45 million. Now note your two Vulcain Ariane 5 or 6 can be reusable a la the F9 by powered landing and also be manned flight capable in no longer having the safety issue of solids. Bob Clark

“Angry Astronaut” is not so enthused on the upgraded Raptor 3 as are other SpaceX fans. He notes what SpaceX should be focused on is improving Raptor reliability and reusability. On the SH/SS flight, a quarter of the engines failed with one and likely two actually exploding. https://www.youtube.com/watch?v=0KYztCHTXaM Bob Clark

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

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

The first solution to the riddle comes from the assumption that from its economy of volume that SuperHeavy/Starship will be THE be-all, end-all for ALL of spaceflight. In point of fact, for EVERY form of transport going back to the horse-drawn era, the transport has always come in different sizes. The point is well illustrated by the example of the jumbo jets. See the highlighted sentence in the article: The largest jumbo jets actually make up a *tiny* proportion, less than 1%, of total air traffic. The same is true of car traffic. The amount of traffic carried by Greyhound buses is a tiny proportion of the traffic carried by passenger cars. Sure, the bus companies and the jumbo jet airliners would love if the majority of passengers were on their vehicles, but THATS NOT WHAT THE CUSTOMERS WANT. The airline companies know this of course. The same airline companies that operate the jumbo jets also operate the smaller aircraft. If those airline companies were to only offer the jumbo jets they would rapidly go out of business. ArianeSpace found a similar phenomenon with the Ariane 5. It was designed to carry separate satellites to orbit. But what they frequently found is that when one satellite was ready to go, ArianeSpace had to wait around for another satellite ready to go for it to be worth launching the Ariane 5. And in point of fact most satellite companies wanted their OWN DEDICATED LAUNCHER. That is the primary reason why ArianeSpace wanted to move to the Ariane 6, so customers could affordably have their own dedicated launchers. The Falcon Heavy gives further evidence of this. The per kilogram cost of the FH is less than the F9. If per kilogram cost was the key thing, then the Falcon Heavy would packed with separate satellites and would be launching as often as the F9. But in point of fact, FH launches have been few and far between, and have only been used when there are satellites that can’t be launched on the smaller launchers, including the F9. As before, the satellite companies want their own dedicated launchers. SpaceX might claim their per kilogram cost will make them preferred but the example of the bus companies and the airlines make that argument extremely dubious. Their own Falcon Heavy also argues against it. Also, I don’t agree their per kilogram cost will in fact be that much cheaper than the other New Space companies. For those other companies know SpaceX was able to cut development cost by 90% by the commercial space approach, i.e., getting private financing rather than government financing. Then consider: when pricing their launch vehicles the largest proportion of that price is not coming from the production cost, but in fact due to the amount added on to recoup the development cost over time. SpaceX has spent $10 billion developing the SuperHeavy/Starship with more billions yet to be spent on the development. This is in the range of 100 times higher than the development cost for the companies with smaller launchers. Then the amount to be added on to the price due to development cost, which again makes up the largest bulk of the customer price, will be radically smaller. Note that SpaceX won’t be superior in price reduction due to reusability either since all the New Space companies also are focusing on reusability. Robert Clark

Brain Teaser: Why does Falcon Heavy disprove the SpaceX justification for building the SuperHeavy/Starship? MAJOR hint: Why did Arianespace want to move away from the Ariane 5 to the Ariane 6? After writing that, it occurred to me there are two different answers to my riddle. Hint for 2nd answer: how many Merlin’s flew on actual operational missions on Falcon 9’s before the Falcon Heavy flew? How many times did the Raptor before the SuperHeavy/Starship? Bob Clark

In addition to the three alarming facts about the launch I discussed previously there was another fact just as alarming, the lean the rocket initiated soon after launch. It was assumed this was commanded by launch control. But Elon revealed this was done by the rocket itself to compensate for the 3 shut down engines: Elon Musk pushes for orbital goal following data gathering objectives during Starship debut written by Chris Bergin May 3, 2023 … “Those engines did not explode, but they were just, the system didn’t think they were healthy enough to bring them to a full thrust,” added Musk during a post-flight Twitter spaces call, adding that is why the vehicle appeared to lean away from the Tower during ascent. It was assumed the lean could have been related to pad avoidance, but Musk quickly noted that it is undesirable due to the “blowing torch” of the Raptor 2 engines on the OLM ring. “If you move sideways sooner, you are moving that big, cutting torch across the launch ring. So, you can think of this thing like the world’s biggest cutting torch, basically. Depending on how close the engines are, they erode that steel at a roughly — I think half an inch to an inch per second of high strength steel is eroded by the cutting torch.” “(The lean was actually) related to the engines out, and we do not normally expect to lean. It should be aspirationally going straight up.”https://www.nasaspaceflight.com/2023/05/musk-orbital-goal-starship-debut/ This is extremely concerning because if this really was a fully automated compensation maneuver then if the shut down engines were on the other side the lean would have been towards the launch tower! The result would have been a catastrophic explosion. Bob Clark

The Angry Astronaut gives an insightful analysis of the environmental lawsuit against the FAA and suggests it could delay another launch from Boca Chica for another two years. The reason is the extent of the spread of concrete debris is beyond the 700 acres implied in the FAA environmental assessment. This means a more detailed environmental impact report must be written. This takes longer, thus suggesting the longer time for another launch license to be granted: Bob Clark

Launch and landing is by same vehicle. SpaceX is still talking about rapid reuse out of Boca Chica, so same issues arise. Bob Clark

I’m suggesting they are being lax to appease SpaceX since SpaceX is currently the only provider of military launches, the only provider for launches to the ISS, and the only provider for a lunar lander for the Artemis missions. So there need to be reviewers independent of both SpaceX and the FAA. Something just occurred to me. If SpaceX previously said the Starship launchpad would be located 20 miles off-shore because of the noise from sonic booms, wouldn’t the same issue apply to the residents of South Padre Island and Port Isabel only 5 to 6 miles away? ELON MUSK: NOISY STARSHIP SPACEPORTS WILL BE 20 MILES OFFSHORE. https://futurism.com/the-byte/elon-musk-starship-spaceports-offshore Bob Clark

Three quite alarming facts were revealed in Elon’s twitter Spaces discussion: Elon Musk - Spaceship update after explosion - Spaces Twitter. https://www.youtube.com/watch?v=pe4B2eIeXfs First, the Raptors likely were not damaged by the concrete thrown up. If so, then 8 Raptors failed on their own during the flight. Second, thrust vector control, TVC, failed at some point during the flight. Third, the FTS took far too long to destroy the vehicle at 40 seconds. These three facts together could have led to catastrophic results to the public. If that many Raptors had failed and without TVC closer to the ground, the FTS would not have been able to destroy it before it was over densely populated area if headed in that direction. The multiple failures of Raptors during tests, and not just shutting down or being shut down, but actually leaking fuel and catching fire, led to my arguing SpaceX should be required by the FAA to construct a separate all-up test stand for full thrust, full flight duration testing. Had this been done then both the launch pad damage and the likely Raptor failures would have been picked up. I also argued there should be an independent review aside from the FAA by space safety experts on the safety of the launch. If so, the inadequacy of the FTS likely also would have been picked up. I say it’s likely it would have been seen beforehand because assuming the FTS did activate there seems to be only one reason why it did not destroy the vehicle immediately: the strength of the explosives used were not sufficient to penetrate beyond the tank wall strength. This SHOULD have been seen beforehand. Tank wall thickness depends on the width of the tanks and the material used. Because of its size, the closest analog to the SuperHeavy stage was the Saturn V’s S-1C first stage. It’s max wall thickness was in the range of ~6.5 mm while for the SuperHeavy it’s in the range of ~8mm, about 25% thicker. BUT it’s also important to remember the specialty high strength stainless steel used on the SuperHeavy is much stronger than the standard aerospace grade aluminum used on the S-1C. Given the greater thickness and greater material strength, these two facts together give a tank wall tensile strength for the SuperHeavy about 3 times higher than that of the S-1C.The amount of explosives used should have been adjusted accordingly. Bob Clark

Well put. Bob Clark

Good point. Has anyone done a frame by frame analysis to see if the flame front expanded at supersonic speed or not? Robert Clark

Thanks. That’s very relevant because of the ground water issue at Boca Chica. Another relevant question is how much total weight had to be supported, bridge plus cars? Robert Clark