Do you know when we need to build heavy-lift vehicles? When there is enough traffic to justify flying them more than once every year or two.
Killer.
At this point we’ve seen the leaked NASA presentation about the NASA depot study, but has the study itself finally been obtained by Rohrabacher or anybody else outside NASA?
so I thought I’d dissect it here, with a through fisking.
Should that be “through” or “thorough”?
@george, he fisked it through and through. And the vorpal sword went snicker-snack.
This and Clark’s piece are two very strong responses. It might also be useful to consider that one way commercial means of transportation lower costs is to share costs with many customers and many different uses. A medium-heavy launcher has a variety of commercial customers, and the infrastructure and development costs can be shared among them. A heavy lifter would find it very hard to locate any customers for quite a while. As a thought experiment, consider a world with our general level of technology but one that had never developed commercial aviation beyond a few light-aircraft uses. Suddenly there is a need to develop heavy-lift Antarctic aviation and build a transport with the capabilities of a C-130. It would only fly a few dozen flights a year. How much would that transport cost to develop and build, not to mention to operate.
I’ve advocated relabeling space tourists as “Citizen-underwriters supporting launch vehicle development”, since that is, functionally, what they are. Sort of like being an NPR donor, except that instead of a coffee mug you get a flight into space. Similarly, by using a commercial-class vehicle with other uses, the commercial customers have the effect of off-loading some of the costs of getting propellant for exploration to orbit. It’s a good deal, and we should take it.
a wasteful distraction supported by the kinds of poorly vetted assumptions that can cause a concept to appear deceptively attractive.
Irony. Beautiful, beautiful irony.
Jim, the C-130 is not the ‘heavy lifter’ of military transport.
C130 Hercules -> around 20 tons payload.
C5 Galaxy -> around 122 tons payload.
Just looking at the wikipedia pages rams the entire “heavy lift” versus “medium lift” debate home. Number of variants, used by number of countries, list of interesting modifications, etc. Here’s a quote from the C5 Galaxy page that sounds like it could be written about the Ares or SLS thing.
“The C-5 Galaxy had a complicated development, signficant cost overruns were experienced and Lockheed suffered significant financial difficulties. ”
or
“After being one of the worst-run programs, ever, in its early years, it has evolved very slowly and with great difficulty into a nearly adequate strategic airlifter that unfortunantly needs in-flight refuelling or a ground stop for even the most routine long-distance flights. We spent a lot of money to make it capable of operating from unfinished airstrips near the front lines, when we never needed that capability or had any intention to use it.”
Robert F. Dorr, aviation historian[12]
Or:
“The C-5 program has the dubious distinction of being the first development program with a one billion dollar overrun”
C130 -> over 2300 built. “One of the safest planes”
C5 -> 131 built. First batch of 81 planes spend 15 years(ish) restricted to half-weight because of wing cracks.
Jim, the C-130 is not the ‘heavy lifter’ of military transport.
C130 Hercules -> around 20 tons payload.
C5 Galaxy -> around 122 tons payload.
Yet, the C-130 carries more cargo.
Heavy lift does not mean you have to put everything on a single flight. Sometimes the military needs to move something like a main battle tank in a hurry, but most of the time, equipment can be disassembled for shipment.
(Of course, it’s the private sector that does the real “heavy lifting” for the military. 80% of military logistics goes by commercial transport. C-130s and C-5s are used only when there are special unique military requirements that commercial flights can’t meet.)
During World War II, the heavy lifter was the C-47 (military version of the DC-3). It was smaller than today’s commuter airliners. Yet, it carried almost everything, including entire fighter planes (with the wings detected for transport), prefabricated buildings, pierced sheet plate runways, horses, you name it.
General Eisenhower named it one of the four machines that won the war in Europe.
In every discussion I have seen on this issue one of the main Fuel Depot selling points is you save the cost of developing an HLV.
Yet a functioning Orbital Propellant Depot System does not exist anymore than an HLV does and none of these critiques of HLV has ever included an estimate of the costs of developing an Orbital Propellant Depot System.
Does such a cost estimate exist and if so could someone provide a link?
Dan Adamo has been a guest on the Space Show a number of times talking about fuel depots. Interesting to listen to and there might be some documentation in the show description or on the blog.
Unfortunately, Dan’s arguments amount to “I’m an expert, trust me”. When pressed, he’ll say he hasn’t actually thought out a good technical argument for why propellant depots won’t work.. it’s just his gut feeling.. but if you’d like to pay him to write a technical report, he’s available.
I like the guy, but that’s laugh-you-out-of-the-room time for a technical audience.
What I took away from the shows listed to was that for depots to be most effective it depends on where they are placed in relation to where you are leaving from and where you want to go.
I remember one show on fuel depots had a professor on that talked about the costs of building a fuel depot to support lunar missions. Not sure if his report was linked at the Space Show. Remember who that guest was Trent?
“What I took away from the shows listed to was that for depots to be most effective it depends on where they are placed in relation to where you are leaving from and where you want to go.”
Which is problem, but not a problem NASA needs to solve. All NASA needs to do is make so vehicles can be refueled and say they would buy the rocket fuel if available.
NASA doesn’t buy a gas station, NASA buys the rocket fuel- if they need it, when they need it, if some party is selling it.
But something like a prototype gas station to determine risks and lower risks, could something NASA could buy- and LEO seems best place for that.
Al, I chose the C-130 because it has been the workhorse of Antarctic operations. That is partly because there are so many of them around, so the disparity between the fully-loaded costs of a vehicle developed for one-time use vs. a multiple-purpose, widely used vehicle would stand out clearly. Of course, if you set out to develop a C-5A equivalent in a world with nothing remotely near its size for one flight every year of two that would be truly horrendous.
Al, I chose the C-130 because it has been the workhorse of Antarctic operations.
Antarctic operations are an interesting example. Building the base at the South Pole required something like 300-400 flights, as I recall. (It’s been a few years since I looked it up.)
That’s why I think it’s so silly when people think they can build a Moon colony using Saturn Vs.
Of course, if you set out to develop a C-5A equivalent in a world with nothing remotely near its size for one flight every year of two that would be truly horrendous.
The Spruce Goose comes to mind.
Mike Griffin wants to build the Space Goose.
Yet a functioning Orbital Propellant Depot System does not exist
Wrong, it actually does. See ISS / Zarya / FGB / Progress. Zarya serves as a depot, for ISS reboosts.
This paper doesn’t give numbers, but it does describe a cryo tank system which can be launched on a Delta IV Heavy, weights about 3 tons (meaning it can be placed probably anywhere in cislunar space, not just the orbit which it was intended for) and store 140 tons of LOX or 15 tons of liquid hydrogen with low to zero boiloff, depending on whether active cooling systems are included. You would need two of these depots to store two propellants.
So that’s something like 400-500 million in launch costs plus whatever the depot costs to develop, build, and operate. Given that it’s a large tank with a heat shield with modest need for station keeping and attitude contol (possibly with an active cooling system down the road), I don’t think it’s going to be very high priced for a satellite.
Also keep in mind this is a cryo system and hence more complicated than a storable propellants system would be. The latter might be able to use some variation of a Bigelow habitat as a propellant bladder.
Excuse me, the Delta IV Heavy is required above because of the 15 foot diameter of the tank.
One thing the SLS advocates haven’t done is to identify the specific payloads that the SLS will carry, and what they will mass. If the payload mass is less than the full capacity of the launch vehicle, then the cost per pound goes up … perhaps way up.
One thing the SLS advocates haven’t done is to identify the specific payloads that the SLS will carry
Yes, and Congressional staffers actually cite the failure to identify specific payloads as an additional reason why SLS must go forward.
Amazingly, that actually makes sense to them.
Dang. If only I could refine that technique … I’d use it on my wife as an additional reason for why buying a Maserati instead of a minivan is absolutely necessary.
I ask again, how far can a federal employee (Griffin) go before it becomes criminal activity that can be prosecuted?
john hare November 5, 2011 at 3:08 pm | # | Reply
“I ask again, how far can a federal employee (Griffin) go before it becomes criminal activity that can be prosecuted?”
Griffen is no longer a “fereral employee”. He has not been for some years now.
I have a silly question on the boil-off of a cryo tank. Why not take the boiled-off hydrogen, mix it with oxygen, and run it through a little thruster to periodically boost the depot into a higher orbit? It’s free propulsion.
You could also heat with sunlight any boil off gas and get enhanced propulsion in that way.
I was thinking you could just burn it in a gaseous hydrogen/oxygen engine, which is about what you were going to do anyway, boosting the tank to a higher orbit, which you’d have liked to do anyway. A better alternative might be running the hydrogen through some type of ion thruster, getting even more efficiency during the long decade of waiting for the crewed stage to arrive on the SLS. So depot’s rendezvous point would just keep getting close to the final destination. It’s a feature, not a bug.
I haven’t heard a reason against it yet, George, though I think the delta-v might be too much for stationkeeping and too little to get anywhere interesting. I’ve been an advocate of taking ‘use the boiloff’ a step further and using the boiled off hydrogen to mix with some oxygen to make water, something else that a visiting crew could get from the depot and not have to lift out of Earth’s gravity well. The water is easy to store, it’s something the crew would need anyway, and can be offset by one additional delivery each of hydrogen and oxygen.
I think the ULA studies propose using hydrogen cold gas monopropellant, which has similar performance to hydrazine. The hydrogen boil-off is used keep the LOX safely away from its boiling point, so there should be no LOX boil-off at all.
Wonderful quote I saw on Twitter today:
“It is difficult to get a man to understand something, when his salary depends upon his not understanding it!” ~ Upton Sinclair
Are you still taking SpaceX money via the competitive space website?
Are you still beating your wife?
On a somewhat related note, Aerojet wants to build reusable solar-powered space tugs.
Do you know when we need to build heavy-lift vehicles? When there is enough traffic to justify flying them more than once every year or two.
Killer.
At this point we’ve seen the leaked NASA presentation about the NASA depot study, but has the study itself finally been obtained by Rohrabacher or anybody else outside NASA?
Should that be “through” or “thorough”?
@george, he fisked it through and through. And the vorpal sword went snicker-snack.
This and Clark’s piece are two very strong responses. It might also be useful to consider that one way commercial means of transportation lower costs is to share costs with many customers and many different uses. A medium-heavy launcher has a variety of commercial customers, and the infrastructure and development costs can be shared among them. A heavy lifter would find it very hard to locate any customers for quite a while. As a thought experiment, consider a world with our general level of technology but one that had never developed commercial aviation beyond a few light-aircraft uses. Suddenly there is a need to develop heavy-lift Antarctic aviation and build a transport with the capabilities of a C-130. It would only fly a few dozen flights a year. How much would that transport cost to develop and build, not to mention to operate.
I’ve advocated relabeling space tourists as “Citizen-underwriters supporting launch vehicle development”, since that is, functionally, what they are. Sort of like being an NPR donor, except that instead of a coffee mug you get a flight into space. Similarly, by using a commercial-class vehicle with other uses, the commercial customers have the effect of off-loading some of the costs of getting propellant for exploration to orbit. It’s a good deal, and we should take it.
a wasteful distraction supported by the kinds of poorly vetted assumptions that can cause a concept to appear deceptively attractive.
Irony. Beautiful, beautiful irony.
Jim, the C-130 is not the ‘heavy lifter’ of military transport.
C130 Hercules -> around 20 tons payload.
C5 Galaxy -> around 122 tons payload.
Just looking at the wikipedia pages rams the entire “heavy lift” versus “medium lift” debate home. Number of variants, used by number of countries, list of interesting modifications, etc. Here’s a quote from the C5 Galaxy page that sounds like it could be written about the Ares or SLS thing.
“The C-5 Galaxy had a complicated development, signficant cost overruns were experienced and Lockheed suffered significant financial difficulties. ”
or
“After being one of the worst-run programs, ever, in its early years, it has evolved very slowly and with great difficulty into a nearly adequate strategic airlifter that unfortunantly needs in-flight refuelling or a ground stop for even the most routine long-distance flights. We spent a lot of money to make it capable of operating from unfinished airstrips near the front lines, when we never needed that capability or had any intention to use it.”
Robert F. Dorr, aviation historian[12]
Or:
“The C-5 program has the dubious distinction of being the first development program with a one billion dollar overrun”
C130 -> over 2300 built. “One of the safest planes”
C5 -> 131 built. First batch of 81 planes spend 15 years(ish) restricted to half-weight because of wing cracks.
Jim, the C-130 is not the ‘heavy lifter’ of military transport.
C130 Hercules -> around 20 tons payload.
C5 Galaxy -> around 122 tons payload.
Yet, the C-130 carries more cargo.
Heavy lift does not mean you have to put everything on a single flight. Sometimes the military needs to move something like a main battle tank in a hurry, but most of the time, equipment can be disassembled for shipment.
(Of course, it’s the private sector that does the real “heavy lifting” for the military. 80% of military logistics goes by commercial transport. C-130s and C-5s are used only when there are special unique military requirements that commercial flights can’t meet.)
During World War II, the heavy lifter was the C-47 (military version of the DC-3). It was smaller than today’s commuter airliners. Yet, it carried almost everything, including entire fighter planes (with the wings detected for transport), prefabricated buildings, pierced sheet plate runways, horses, you name it.
General Eisenhower named it one of the four machines that won the war in Europe.
In every discussion I have seen on this issue one of the main Fuel Depot selling points is you save the cost of developing an HLV.
Yet a functioning Orbital Propellant Depot System does not exist anymore than an HLV does and none of these critiques of HLV has ever included an estimate of the costs of developing an Orbital Propellant Depot System.
Does such a cost estimate exist and if so could someone provide a link?
Dan Adamo has been a guest on the Space Show a number of times talking about fuel depots. Interesting to listen to and there might be some documentation in the show description or on the blog.
http://www.thespaceshow.com/guest.asp?q=697
Unfortunately, Dan’s arguments amount to “I’m an expert, trust me”. When pressed, he’ll say he hasn’t actually thought out a good technical argument for why propellant depots won’t work.. it’s just his gut feeling.. but if you’d like to pay him to write a technical report, he’s available.
I like the guy, but that’s laugh-you-out-of-the-room time for a technical audience.
What I took away from the shows listed to was that for depots to be most effective it depends on where they are placed in relation to where you are leaving from and where you want to go.
I remember one show on fuel depots had a professor on that talked about the costs of building a fuel depot to support lunar missions. Not sure if his report was linked at the Space Show. Remember who that guest was Trent?
“What I took away from the shows listed to was that for depots to be most effective it depends on where they are placed in relation to where you are leaving from and where you want to go.”
Which is problem, but not a problem NASA needs to solve. All NASA needs to do is make so vehicles can be refueled and say they would buy the rocket fuel if available.
NASA doesn’t buy a gas station, NASA buys the rocket fuel- if they need it, when they need it, if some party is selling it.
But something like a prototype gas station to determine risks and lower risks, could something NASA could buy- and LEO seems best place for that.
Al, I chose the C-130 because it has been the workhorse of Antarctic operations. That is partly because there are so many of them around, so the disparity between the fully-loaded costs of a vehicle developed for one-time use vs. a multiple-purpose, widely used vehicle would stand out clearly. Of course, if you set out to develop a C-5A equivalent in a world with nothing remotely near its size for one flight every year of two that would be truly horrendous.
Al, I chose the C-130 because it has been the workhorse of Antarctic operations.
Antarctic operations are an interesting example. Building the base at the South Pole required something like 300-400 flights, as I recall. (It’s been a few years since I looked it up.)
That’s why I think it’s so silly when people think they can build a Moon colony using Saturn Vs.
Of course, if you set out to develop a C-5A equivalent in a world with nothing remotely near its size for one flight every year of two that would be truly horrendous.
The Spruce Goose comes to mind.
Mike Griffin wants to build the Space Goose.
Yet a functioning Orbital Propellant Depot System does not exist
Wrong, it actually does. See ISS / Zarya / FGB / Progress. Zarya serves as a depot, for ISS reboosts.
This paper doesn’t give numbers, but it does describe a cryo tank system which can be launched on a Delta IV Heavy, weights about 3 tons (meaning it can be placed probably anywhere in cislunar space, not just the orbit which it was intended for) and store 140 tons of LOX or 15 tons of liquid hydrogen with low to zero boiloff, depending on whether active cooling systems are included. You would need two of these depots to store two propellants.
So that’s something like 400-500 million in launch costs plus whatever the depot costs to develop, build, and operate. Given that it’s a large tank with a heat shield with modest need for station keeping and attitude contol (possibly with an active cooling system down the road), I don’t think it’s going to be very high priced for a satellite.
Also keep in mind this is a cryo system and hence more complicated than a storable propellants system would be. The latter might be able to use some variation of a Bigelow habitat as a propellant bladder.
Excuse me, the Delta IV Heavy is required above because of the 15 foot diameter of the tank.
One thing the SLS advocates haven’t done is to identify the specific payloads that the SLS will carry, and what they will mass. If the payload mass is less than the full capacity of the launch vehicle, then the cost per pound goes up … perhaps way up.
One thing the SLS advocates haven’t done is to identify the specific payloads that the SLS will carry
Yes, and Congressional staffers actually cite the failure to identify specific payloads as an additional reason why SLS must go forward.
Amazingly, that actually makes sense to them.
Dang. If only I could refine that technique … I’d use it on my wife as an additional reason for why buying a Maserati instead of a minivan is absolutely necessary.
I ask again, how far can a federal employee (Griffin) go before it becomes criminal activity that can be prosecuted?
john hare November 5, 2011 at 3:08 pm | # | Reply
“I ask again, how far can a federal employee (Griffin) go before it becomes criminal activity that can be prosecuted?”
Griffen is no longer a “fereral employee”. He has not been for some years now.
I have a silly question on the boil-off of a cryo tank. Why not take the boiled-off hydrogen, mix it with oxygen, and run it through a little thruster to periodically boost the depot into a higher orbit? It’s free propulsion.
You could also heat with sunlight any boil off gas and get enhanced propulsion in that way.
I was thinking you could just burn it in a gaseous hydrogen/oxygen engine, which is about what you were going to do anyway, boosting the tank to a higher orbit, which you’d have liked to do anyway. A better alternative might be running the hydrogen through some type of ion thruster, getting even more efficiency during the long decade of waiting for the crewed stage to arrive on the SLS. So depot’s rendezvous point would just keep getting close to the final destination. It’s a feature, not a bug.
I haven’t heard a reason against it yet, George, though I think the delta-v might be too much for stationkeeping and too little to get anywhere interesting. I’ve been an advocate of taking ‘use the boiloff’ a step further and using the boiled off hydrogen to mix with some oxygen to make water, something else that a visiting crew could get from the depot and not have to lift out of Earth’s gravity well. The water is easy to store, it’s something the crew would need anyway, and can be offset by one additional delivery each of hydrogen and oxygen.
I think the ULA studies propose using hydrogen cold gas monopropellant, which has similar performance to hydrazine. The hydrogen boil-off is used keep the LOX safely away from its boiling point, so there should be no LOX boil-off at all.
Wonderful quote I saw on Twitter today:
“It is difficult to get a man to understand something, when his salary depends upon his not understanding it!” ~ Upton Sinclair
Are you still taking SpaceX money via the competitive space website?
Are you still beating your wife?
On a somewhat related note, Aerojet wants to build reusable solar-powered space tugs.
http://www.daytondailynews.com/business/aerojet-looks-at-space-tugs-1279977.html