News SPACEX Falcon Heavy Teaser

[Ark]

As for what it can lift. Why not extremely heavy and or bulky cargo?

Who is lifting heavy and bulky cargo anymore? The station is more-or-less complete and nobody else is planning anything of that scale.

 

[Sky Captain]

SpaceX claim 53 tons to LEO, that is 5X of Falcon9 capability. How are they supposed to achieve that much increase of performance with addition of only two extra booster cores. Previously it was said Falcon9 will have 32 tons to LEO payload. Is it because boosters feed fuel to the center core?
The Falcon9 has launch mass of 333 tons, the Falcon9 will have 1400 tons yet its first stage will consist of 3 Falcon9 cores. Where did the extra 400 tons came from? Something doesn't add up there.

 

[Zachstar]

This I am not sure at all about but if the station gets extended (Which I highly doubt but putting it out there) Would you not need external supplies for more detailed repair work and science work? I had thought one of the design goals of dragon was to be able to launch it as an external cargo carrier in the future.

 

[Ark]

This I am not sure at all about but if the station gets extended (Which I highly doubt but putting it out there) Would you not need external supplies for more detailed repair work and science work? I had thought one of the design goals of dragon was to be able to launch it as an external cargo carrier in the future.

I just have doubts about investing that much in a launcher that might not have a market. They built the Saturn V because we wanted to fly to the moon, we didn't decide to fly to the moon because someone built a Saturn V.

 

[Jarvitä]

SpaceX claim 53 tons to LEO, that is 5X of Falcon9 capability. How are they supposed to achieve that much increase of performance with addition of only two extra booster cores. Previously it was said Falcon9 will have 32 tons to LEO payload. Is it because boosters feed fuel to the center core?
The Falcon9 has launch mass of 333 tons, the Falcon9 will have 1400 tons yet its first stage will consist of 3 Falcon9 cores. Where did the extra 400 tons came from? Something doesn't add up there.

Longer core stage, more powerful second stage? SpaceX is being more secretive than normally here.

 

[Zachstar]

I just have doubts about investing that much in a launcher that might not have a market. They built the Saturn V because we wanted to fly to the moon, we didn't decide to fly to the moon because someone built a Saturn V.

Yes but this is different. It might give them an option if large external repairs are needed. Some of the ISS modules are over a decade old now and keeping them going into the 2020s is likely going to need some tricky and large scale repair work in my opinion. (For instance how is the condition of the MMOD shielding?) If this gives an option it might be worth perusing for NASA and the ISS partners.

And if no market develops? They don't have to build it and it seems to be minimal cost to have it designed and on file in case of need in the future.

 

[Sky Captain]

Longer core stage, more powerful second stage? SpaceX is being more secretive than normally here.

Then they will need more powerful engines because 27 Merlin 1 won't lift 1400 tons of the pad.

---------- Post added at 11:42 PM ---------- Previous post was at 11:32 PM ----------

Speaking of market for Falcon Heavy. If it works as advetised capable of placing 53 tons into LEO or ~30 tons into GTO and costs only 125 million would there be any advantages of building heavier, but cheaper comsats. As far as I understand sattelites are so expensive because companies try to shave off every possible gram to be able to use smaller and cheaper rocket. If a powerful, but cheap rocket is available could it be advantegous cost vise to use heavier but cheaper (maybe more off the shelf componenets) parts to make a relatively cheap, but heavy comsat?

 

[Capt_hensley]

On heavy Lift "Need"

Since Obama shot down Bushes goal of going back to the moon, and Obama shot down going to Mars anytime soon, since Ares 1 is paused, and Ares V is all but canceled, NASA has an "Unofficial" need for heavy lift and manned capsules. Just because NASA can't fund it, doesn't mean they don't need it.

Enter Obama, "Commercial ventures pick up the slack..."

Now Russia had, again "had" some nice heavy lift resources, but have canceled all of them due specifically to lack of funds, not lack of missions, just who do we look to for HLVs?

Delta and Atlas are great, but are small when placed next to the Ares V and Falcon XX HLVs. Everybody knows we need HLVs to work any mission on the Moon, Mars, or interplanetary exploration.

Japan has a nice HII, ESA has a nice Ariane, but they both fall just shy of the HLV capacity needed for a long term mission. ISRO is way behind, but at least thinking GEO.

I say the argument for HLV is made, and has been for a long time, someone has to step up without Gov funding. X-Prize and Lunar X-Prize competition provided both seed money, and incentive. Nothing more need be done to inspire commercial venture.

Don't forget even though IOS is sending up the Neptune 30, with 30 commercial packages, like Space X they are a few years from HLV, but even they know HLV has a place in the next race. Like Space X they are building the basic blocks to get them in the race. Sure its slow, so what!

Space X is just planning and working in logical steps toward the inevitable goal of commercial HLV, Who cares who the customer is or where the money comes from! Nuf said...

Great job on the promo vid.

---------- Post added at 08:53 PM ---------- Previous post was at 08:50 PM ----------

Then they will need more powerful engines because 27 Merlin 1 won't lift 1400 tons of the pad.

Enter "Merlin 2" check the propulsion guide from one of my previous posts.

---------- Post added at 08:57 PM ---------- Previous post was at 08:53 PM ----------

Yes but this is different. It might give them an option if large external repairs are needed. Some of the ISS modules are over a decade old now and keeping them going into the 2020s is likely going to need some tricky and large scale repair work in my opinion. (For instance how is the condition of the MMOD shielding?) If this gives an option it might be worth perusing for NASA and the ISS partners.

And if no market develops? They don't have to build it and it seems to be minimal cost to have it designed and on file in case of need in the future.

Probably wont be an issue, repairs on the scale you suggest aren't worth the risks at this point in the game.

However what will replace the ISS? Whatever and whenever it is, it won't get to orbit without HLVs. STS is dead, D E D, dead.

 

[Urwumpe]

I suspect there is a lot of data optimization going on.

The Falcon 9 is said to lift 16 tons to LEO, but previously it had been just 11 tons, which put it closer to the Zenit-2 in payload.

 

[Capt_hensley]

I suspect there is a lot of data optimization going on.

The Falcon 9 is said to lift 16 tons to LEO, but previously it had been just 11 tons, which put it closer to the Zenit-2 in payload.

I suspect you're right.

I found conflicting data on the Space X web site itself. The documents are out of date, I've already let them know and they are working on the site and user guides. Falcon 9 Heavy has no user guide just the web page, as for FX and FXX, they say these are just ideas. I think not, but we have to wait for documentation.

Check your figures, some are in Kgs, others in Lbs

 

[Urwumpe]

Check your figures, some are in Kgs, others in Lbs

I try to reconstruct the performance by some spreadsheeting, after all, there is really little for SpaceX to make better than a Zenit launcher - the engines are gas generator cycle, so it is guaranteed the chamber pressure will be 69 atm, and thus the vacuum specific impulse at the optimum for kerolox gas generator cycle engines.

The only point where they can be better is the structural mass. But currently, I don't get a configuration there, that reaches even just the 3.3% that is claimed for the "new Falcon 9" today. I just get 3% and thus a bit more than the 2.8% of the Falcon 9 with the old data.

 

[Capt_hensley]

I try to reconstruct the performance by some spreadsheeting, after all, there is really little for SpaceX to make better than a Zenit launcher - the engines are gas generator cycle, so it is guaranteed the chamber pressure will be 69 atm, and thus the vacuum specific impulse at the optimum for kerolox gas generator cycle engines.

The only point where they can be better is the structural mass. But currently, I don't get a configuration there, that reaches even just the 3.3% that is claimed for the "new Falcon 9" today. I just get 3% and thus a bit more than the 2.8% of the Falcon 9 with the old data.

Way over my head dude,(I'm just a beginner) but I here ya, kinda

If I may interpret? you don't see how the new Merlin 2 can be better than the old Merlin 1D, maybe a 3% overall gain in power and lift, right? A Zenit 3SL(B) {Zenit 2, is no longer in use from what I read}is the best they could match... Which would be to stick with a single body main stage, and improve (lighten) the mass of the second stage to improve the max altitude. If I read the above correctly, Please elaborate as if I were not a science PHD(because I'm not a science PHD) Thanks

PS You've got it together and I value your input and experience, I know you can help me learn, I just have to understand the lesson.

 

[Sky Captain]

IIRC Merlin2 was supposed to be with similar thrust to RD180. Their launch animation showed Falcon Heavy with 27 regular Merlin1 engines. Either they plan to upgrade Merlin1 to higher performance or something is wrong with their numbers because 27 Merlin1 can't lift 1400 tons off the pad. Merlin1 have thrust of 550kN. 27 of them will generate 14850 kN which will give Falccon Heavy T/W ratio of ~1:1 clearly not enough for efficient launch

 

[Urwumpe]

If I may interpret? you don't see how the new Merlin 2 can be better than the old Merlin 1D, maybe a 3% overall gain in power and lift, right?

Not in thrust, but in specific impulse, the more critical number to evaluate the performance of a launcher. You can raise thrust easily by just burning more fuel at the same time, but how much thrust you get per kg fuel burned, that is limited by a few factors.

First of all, you have combustion temperature and average exhaust molecular mass. Higher temperatures are good, and lighter exhaust molecules are good. But both are defined by the propellants you use. You can make your rocket less effective by choosing a less than optimal mixture ratio (optimal mixture ratio is not always the one where all fuel and oxidizer is burned), but you can't make it better than the optimum for the chemistry.

Next, you can raise chamber pressure and expansion ratio. Both higher means better performance. But there are limits to both. Chamber pressure can't be raised on gas-generator cycle engines beyond 69 atm (for kerosene and LOX), because you would otherwise need to burn too much propellant for driving the pumps, than will not contribute to thrust.

Expansion ratio is limited again by the ambient air pressure in which the engine should operate, and the mass of the engines itself. During lift-off, you want to have the exit pressure only slightly above sea level pressure, because this is the most effective setting. Higher expansion ratio = lower pressure at the exit and you choke your engine at too high ambient pressure, thrust and specific impulse drops a lot. If you reduce the expansion ratio, the specific impulse and thrust drops again because the nozzle does not accelerate the exhaust as much as it could before.

There are small factors that you can use for raising the performance left, but all of the big factors that have significant changes are set.

You could for example run fuel and oxidizer through heat exchangers before combustion for raising combustion temperature a bit. This is then limited by the effectivity of the heat exchangers and the phase limits of the propellants.

The biggest change though, would be by using a different engine cycle. But this means higher costs. Even old Russian engines should be more costly than the Merlin engines of SpaceX, which are really oldest proven technology.

In terms of engine costs, the next best cycle would be the expander cycle, in which you drive your pumps by boiling some propellant in the combustion chamber heat exchangers. But this one limits the maximum thrust, since you can only boil so much of the propellants by burning these propellants later. But you can get enough energy from the gases before injecting them into the combustion chamber, to raise the pressure of the engines to 300-400 atm.

This is followed by the Full-Flow-Staged-Combustion (FFSC) cycle. Currently only some selected Russian engines use it, the most powerful rocket engines ever build had been FFSC. It is essentially like Staged Combustion (what is used in the SSMEs), but instead of running only hot exhaust gases through the turbines, you mix exhaust and propellants before the turbines and let the whole flow go through the turbines. This lowers temperatures at the turbines and permits some cost savings there, also it is the only engine cycle that allows high thrust and very long burn times - ideal for reusing the engines. Both FFSC and SC are the most effective engine cycles currently, because they achieve both very high pressures in the engines.

There is a limit for FFSC and SC engines in terms of chamber pressure again, but it is currently far beyond what the materials permit. Practically, you can reach about 450 atm in a FFSC or SC engine with modern materials, but most engines are still operating at less than 350 atm. The important limitation there is the pressure of the preburners - for injecting the propellants into the engines, the propellants have to be brought to pressures that are about 20 atm higher than the chamber pressure. Much less is not possible there, since you need to spray the propellants into the engines, atomize them and mix them.

So, maybe I explained it a bit better now, why rocket engines can't be improved for all eternity.

A Zenit 3SL(B) {Zenit 2, is no longer in use from what I read}is the best they could match...

Zenit 2 is still marketed and used.

 

[Jarvitä]

Then they will need more powerful engines because 27 Merlin 1 won't lift 1400 tons of the pad.

Wrong.

http://www.wolframalpha.com/input/?i=(27*+556+kN)+/+1400+metric+tons

It would take off only slightly slower than the Saturn V. Or slightly faster, if it uses the Merlin 1D engines with a sea-level thrust of 620 kN.

 

[Urwumpe]

Wrong.

http://www.wolframalpha.com/input/?i=(27*+556+kN)+/+1400+metric+tons

Also wrong. 10.7 m/s² means you just have 0.9 m/s² effective acceleration on leaving the pad. While it is enough to slowly lift-off, it means you consume too much fuel for getting off the pad. You would need 15 seconds just for traveling the first 100m at that acceleration. And your rocket would need 30 seconds for exceeding 100 km/h. My car is even better than that.

 

[N_Molson]

Spaceflight Now :

SpaceX enters the realm of heavy-lift rocketry

A new kerosene-fueled super-rocket being developed by SpaceX should be ready for a test flight from the California coast by 2013, introducing a cost-effective fire-breathing booster three times cheaper and twice as capable as its competitors, the company's founder announced Tuesday.

The Falcon Heavy rocket, an evolved version of the medium-lift Falcon 9 rocket, will be shipped to Vandenberg Air Force Base in California by the end of 2012. Liftoff of the 227-foot-tall launcher should occur sometime in 2013, according to Elon Musk, SpaceX's founder and CEO.

Powered by 27 Merlin engines, the massive rocket will soar into space on 3.8 million pounds of thrust and deliver up to 117,000 pounds into a 120-mile-high low Earth orbit, more than twice the lift capacity of the space shuttle or the Delta 4-Heavy rocket.

"This is a rocket of truly huge scale," Musk said. "117,000 pounds is more than a fully loaded Boeing 737 with 136 passengers, luggage and fuel."

It could fire more than 30,000 pounds straight to Mars, Musk told reporters at the National Press Club in Washington.

Just as eye-popping as the Falcon Heavy's power is its price.

SpaceX announced the new rocket will cost between $80 million and $125 million per mission. Do the math and you'll see the Falcon Heavy could place payloads into orbit for $1,000 per pound, a fraction of the cost of competitors.

"Falcon Heavy represents a huge economic advantage," Musk said. "Falcon Heavy costs about a third as much per flight as a Delta 4-Heavy but carries twice as much payload to orbit, so it's effectively a six-fold improvement in the cost per pound to orbit."

The Falcon Heavy's game-changing capability and price led to questions on Musk's sales pitch.

The high-tech tycoon responded by highlighting the synergy between the heavy-lift rocket and the existing Falcon 9 design, the consistency of SpaceX's earlier launch cost projections and plans to drastically expand the company's production facilities in Hawthorne, Calif.

Musk was also bullish on the Falcon Heavy's flight rate, saying he expects it to launch 10 times a year. He forecasts another 10 flights of the Falcon 9 rocket annually, bringing SpaceX's projected overall flight rate to nearly two missions per month.

"We expect to be launching Falcon Heavy a lot," Musk said. "Falcon 9 can address about half the market. Falcon Heavy can address the other half of the market, which is the largest government and commercial satellites, as well as opening up new market opportunities for satellites and spacecraft that simply cannot be carried to space by the currently available rockets."

Even if his ambitious flight rate doesn't materialize, Musk said he could hold Falcon Heavy's launch price where it is with as few as four flights per year.

SpaceX might need an emerging market to find enough payloads to fill that many missions. Four Falcon Heavy flights a year would double the world's annual space lift capacity.

Artist's concept of the Falcon Heavy rocket. Credit: SpaceX

Although the first Falcon Heavy flight will blast off from Space Launch Complex 4 at Vandenberg, subsequent missions would mostly originate from either SpaceX's existing launch pad or a retired space shuttle facility at Cape Canaveral, Fla.

Musk said the inaugural mission from California will be paid for by SpaceX as a demo flight, but he is "highly confident" the company can sign a U.S. government or commercial customer for the second mission.

He said SpaceX is in an "advanced stage of discussions" with government and commercial clients for Falcon Heavy launch deals.

According to SpaceX, the Falcon Heavy will be designed to meet NASA's published human-rating standards. Its structures will be able to withstand forces 40 percent higher than normal flight environments, it will have triple-redundant avionics and could recover to still reach orbit after the loss of an engine.

The Falcon Heavy is not quite big enough to compete with the Space Launch System, a heavy-lift rocket being designed by NASA to haul nearly 200,000 pounds into orbit.

SpaceX is one of several companies working under small study contracts with NASA to evaluate commercial suggestions for the government-run heavy-lift system. Musk said he has ideas for an even larger SpaceX heavy-lifter to challenge the Space Launch System in the future.

 

[Capt_hensley]

Numbers Debate

From what I read here, there are some source numbers that are bad, and they are coming from Space X.

I know of 4 engines from Space X:
Merlin 1C
Merlin 1D
Merlin Vacuum
Merlin 2

The Merlin 1D is used on Falcon 9(9ea), Falcon 9H(27ea), Falcon X/H(27ea)
The Merlin 2 will upgrade the Falcon 9(3ea) Falcon 9H(9ea) and are standard in Falcon X/H(9ea), Falcon XX(6ea) as shown in the attached chart.

How would you evaluate the numbers given at the bottom of the chart for mass to LEO? Are they right?

 

[Urwumpe]

How would you evaluate the numbers given at the bottom of the chart?

Can't tell much about it, except that they would at least pass a sanity check.

 

[Gerdih]

what stands for Engine Out Capability?