Author Topic: The Reaction Engines Skylon Master Thread (5)  (Read 421991 times)

Offline RanulfC

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #140 on: 03/03/2015 08:47 PM »
If it's just the engine cycle itself, ie the thermodynamic cycle, then it probably doesn't need to include any specific  information on the heat exchangers and frost control mechanisms.

And is it the SABRE 3 or SABRE 4 engine cycle?

What might the USAF gain from studying the thermodynamics of the engine cycle?  ie what applications or insights might it give them for future planning? Is it like JS19 suggests - the only real reason for studying the cycle in this engine is to look at possible applications for launch capacity only.

"Deep-cooled" airflow is actually useful in applications NOT related to launch but not many. On the other hand NO thermodynamic data is useless so even if the USAF is not interested in SABRE as a cycle or for launch purposes there's information to be had :)

Randy
From The Amazing Catstronaut on the Black Arrow LV:
British physics, old chap. It's undignified to belch flames and effluvia all over the pad, what. A true gentlemen's orbital conveyance lifts itself into the air unostentatiously, with the minimum of spectacle and a modicum of grace. Not like our American cousins' launch vehicles, eh?

Offline RanulfC

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #141 on: 03/03/2015 09:11 PM »
Any chance we can hack a ramp into the bottom of the payload bay for paratrooper deployment? Baumgartner up some airborne troops and fire them off the back of the ramp.

How does the payload bay compare to a c130 in number of troopers. And can the craft slow down long enough and low enough to deploy them and then land far downrange? :)

Or maybe a disposable frame that gets ejected and then drops the troops.
Welcome to the forum.

The bay is about  4.8m wide and about 16 m long. There is no option for a "tail ramp" type drop.

Not wanted or needed for supersonic drops anyway the air "above" the airframe is less disturbed and smoother in a relative way. And to prevent serious scatter and/or injury you'd want to eject the personnel in a pod of some type. We (the US) actually did some studies of dropping troops from a B-58 using the under-slung pod in a wind tunnel. Again the major problem was you can drop a whole company and supplies from a sub-sonic C-130 and get the job "done" where as specialized insertion has much less margin for supplies and more troops. It would take as squadron of B-58s to put the same number of boots (and kit) on the ground as one C-130 and the C-130 does it more efficiently and accurately as well.
(BTW: Studies have been done on supersonic and even hypersonic troop and supply drop and while you can use a "tail-ramp" it ends up being on TOP of the airframe and you have to chuck the stuff past the shockwave with something like a catapult so again, not very effective overall. Oh and you have to actually "pressurize" the bay to prevent sucking the shockwave into the airframe in order to "open-up" at supersonic speeds)

In retrospect it would actually have been neat to be able to have the option of supersonic dash into AO, drop to high-subsonic and dump the payload pod, then dash back up to supersonic for egress. But you still have all the issues of inserting into hostile territory with minimum forces that is inherent in the system. Hmmm, something more like a supersonic "Pack-Plane" maybe? (http://en.wikipedia.org/wiki/Fairchild_XC-120_Packplane) But the differences between with and without aerodynamics would probably be prohibitive let alone hypersonic and/or suborbital...

And on top of it all you have an institutional dislike of cryogenic fluids if they can at all be avoided...

Quote
Unfortunately you're either going to need various bases at different longitudes to minimize plane change payload losses or  you have a fairly small minimum team the system can use.

If the vehicle is staying orbital to land further along track or plane change back to its launch base that means the personnel are carrying out individual reentries, or you have to do an orbital ejection of a re entry capable lander module while keeping the vehicle in tact. Either way a huge challenge.  Probably the closest to this architecture is the "Q bay" of the U2 and it's developments, built as a simple rectangular duct running top to bottom, but I'm not sure what facilities it supplied to the payload or if they were more or less self contained.

DROP TROOPERS! :)
U2: Power and air conditioning as far as I know. The constraints were that the equipment had to fit into the bay and work on the provided air and electric.

Quote
Option B is to have the vehicle already into a reentry so a chunk of velocity is already lost. Now you're looking at something like an ejection. The highest is about M3 from an SR71, however it seems due to the altitude (around 80 k feet) which apparently equates to something like 400mph.

This is one of those sounds-cool-but-is-really-nonsense ideas that's great for the plot of a straight-to-download action movie.

IRL not really that good.  :(

Still need a pod or something to hold the troops together unless they individually have some sort of propulsion and guidance. HALO's do something similar from similar altitudes but they have control over their positioning during drop which a supersonic drop would not have. (Imagine your "average" Marine's full kit. Now put a spacesuit on it and him and ask him to perform "simple" maneuvers in the gear. There's a reason the military was interested in the results of high altitude parachuting before Baumgartner did it :) )

And again you get about twice the useful payload to the target with a C-130 than you would with a Skylon under these circumstances...

Randy
From The Amazing Catstronaut on the Black Arrow LV:
British physics, old chap. It's undignified to belch flames and effluvia all over the pad, what. A true gentlemen's orbital conveyance lifts itself into the air unostentatiously, with the minimum of spectacle and a modicum of grace. Not like our American cousins' launch vehicles, eh?

Offline RanulfC

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #142 on: 03/03/2015 09:16 PM »
Any chance we can hack a ramp into the bottom of the payload bay for paratrooper deployment? Baumgartner up some airborne troops and fire them off the back of the ramp.

How does the payload bay compare to a c130 in number of troopers. And can the craft slow down long enough and low enough to deploy them and then land far downrange? :)

Or maybe a disposable frame that gets ejected and then drops the troops.

Capacity: Skylon is this role would be around 15mT where as the C-130 delivers 33mt so about half what a C-130 could do and how much of it is going to be required for support and equipment to keep the troops safe from take off to "landing" is a key issue.

Randy
From The Amazing Catstronaut on the Black Arrow LV:
British physics, old chap. It's undignified to belch flames and effluvia all over the pad, what. A true gentlemen's orbital conveyance lifts itself into the air unostentatiously, with the minimum of spectacle and a modicum of grace. Not like our American cousins' launch vehicles, eh?

Offline RanulfC

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #143 on: 03/03/2015 09:22 PM »
Just considering the first one then, since they would seem impossible to reconcile,...

Welcome as well :)

Oh not "impossible" of course, what the military wants they will, usually, eventually get but really, really hard to reconcile to say the least :)

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... what they have in mind would seem to be an LH2-fuelled skylon-like carrier, dropping a jet-fuelled lander (since ability to retrieve troops and craft was a desired characteristic), equipped with heat shielding.

Even if a suitable heat shield material was available, the main problem seems to be with the skyon-like carrier - what happens to it after release? If it goes to orbit once-around, then maximum payload for the lander is limited to in the region of Skylon's 15 tons. If it is on a suborbital trajectory, it would re-enter in uncontrolled airspace, and would have to be refuelled at a LH2-capable runway.

Or Tanker and air-to-air refueling. LH2 is still considered (and researched) as a possible aircraft fuel after all. And technically the Skylon could, if suborbital, still retain enough propellant to egress the insertion area and fly to meet such a tanker once all was said and done.

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Build a heat-shielded jet aircraft lighter than 15 tons or maintain a network of LH2-capable runways in hostile regions, neither seems particularly feasible

Well a quick (few minutes) search of NTRS doesn't find what I'm looking for but I'll say the idea has been looked at before. Around 1965 IIRC there was a NASA tech-note on the idea of a orbital or suborbital system that had a reentry vehicle that deployed itself as a Mach-2 fighter or (5 or 6 person IIRC) aircraft once it entered the "area or operations" on arrival. Not in any way as efficient as a purpose built aircraft mind you but do-able as far as the study could tell.

The main problem with SUSTAIN/HOT-EAGLE wasn't that it was not possible but that the idea of inserting a handful (biggest body I ever saw mentioned was a company but the usual group was a squad) of troops with no heavy weapons or support and expecting them to actually DO anything even if no one noticed their arrival.

It was an attempt to replace stealth with speed with the idea that getting the troops to the "trouble" location within minutes of being alerted replacing getting enough troops and equipment to be effective and it didn't make a whole lot of sense from the start.

It's simply not enough force to do any job given that the insertion is so non-stealthy in the first place. A Marine recon squad "ready-to-go" massed more than the notional troops that were supposed to be inserted by the system and THEY get things like SF-stealth helicopters to ride in :)

Again the main issue is even if you got the troops there, intact with minimum or no notice by the locals they are very few and with no real equipment or support and no capability for self extraction or retrieval without additional resources already in place.

We've a thread on the concept IIRC if anyone wants to resurrect it but its been years. (Then again I don't think I ever got to fully explore some of the concepts that came around under that heading. The Falcon-9 with the with an aeroshell that landed a folded up Blackhawk and crew/soldiers was, I thought a nice attempt at addressing the issues :) )

Randy
From The Amazing Catstronaut on the Black Arrow LV:
British physics, old chap. It's undignified to belch flames and effluvia all over the pad, what. A true gentlemen's orbital conveyance lifts itself into the air unostentatiously, with the minimum of spectacle and a modicum of grace. Not like our American cousins' launch vehicles, eh?

Offline john smith 19

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #144 on: 03/03/2015 11:41 PM »

In retrospect it would actually have been neat to be able to have the option of supersonic dash into AO, drop to high-subsonic and dump the payload pod, then dash back up to supersonic for egress. But you still have all the issues of inserting into hostile territory with minimum forces that is inherent in the system. Hmmm, something more like a supersonic "Pack-Plane" maybe? (http://en.wikipedia.org/wiki/Fairchild_XC-120_Packplane) But the differences between with and without aerodynamics would probably be prohibitive let alone hypersonic and/or suborbital...
This is OT but this idea still looks a sensible notion to maximize the use of expensive assets. I don't think anyone doubts that the ISO container has revolutionized how quickly goods can be be moved as holds no longer need to be individually loaded.
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DROP TROOPERS! :)
U2: Power and air conditioning as far as I know. The constraints were that the equipment had to fit into the bay and work on the provided air and electric.
Which sounds like quite a fair trade off. The SR71 had the detachable nose and various sensors on pallets for the different bays but only the U2 had a full through  bay with no floor.
Quote
Still need a pod or something to hold the troops together unless they individually have some sort of propulsion and guidance. HALO's do something similar from similar altitudes but they have control over their positioning during drop which a supersonic drop would not have. (Imagine your "average" Marine's full kit. Now put a spacesuit on it and him and ask him to perform "simple" maneuvers in the gear. There's a reason the military was interested in the results of high altitude parachuting before Baumgartner did it :) )

And again you get about twice the useful payload to the target with a C-130 than you would with a Skylon under these circumstances...
I also think it's pretty clear that whatever such a vehicle would be it's definitely not a Skylon anymore.

TBH the "simplest" (and I use the word very loosely) would be to fly the Skylon upside down and drop the pot out the way it came in.

Conceptually simple but IRL insane  :(
"Solids are a branch of fireworks, not rocketry. :-) :-) ", Henry Spencer 1/28/11  Averse to bold? You must be in marketing."It's all in the sequencing" K. Mattingly.  STS-Keeping most of the stakeholders happy most of the time.

Offline Asteroza

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #145 on: 03/05/2015 06:49 AM »
UK spaceport selection shortens the short list...

https://www.gov.uk/government/news/industry-backs-governments-spaceport-plans

but still aiming at 3000m+ runway. Enough for build+ferry ops?

Offline Paul451

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #146 on: 03/05/2015 10:33 AM »
Approx. 97% off-topic:

http://en.wikipedia.org/wiki/Fairchild_XC-120_Packplane
This is OT but this idea still looks a sensible notion to maximize the use of expensive assets. I don't think anyone doubts that the ISO container has revolutionized how quickly goods can be be moved as holds no longer need to be individually loaded.

The Packplane concept (and Skylon equivalent) is not analogous to ISO containers. Shipping containers are much smaller than the ships that carry them. Ditto palletised cargo that goes in a shipping container or truck box. The pallets/container are much smaller than the cargo-carrier so that you don't have to worry about the vehicle size. A 2 pallet van, a 2x2x5 pallet truck, a 2x2x10 pallet ISO shipping container...  A single 2-TEU skeleton trailer, a double-stack 2-TEU train carriage, a 36-TEU river barge, a 5,000-TEU Panamax, etc.

But there's no shipping equivalent of the Packplane, where you have a single removable module that becomes a ship's entire hold, even though ships similar to an empty Packplane exist for other purposes, so it's not a structural issue. It would be simple to design a roll-on/roll-off giant freight module for such a ship, but each semi-submersible platform-ship is a unique size, therefore each giant freight module would be bespoke to each ship. You can see where this is going...

Similarly, instead of a Packplane, the air-freight equivalent of ISO containers are the much smaller ULD containers, light pallets with corner cutaways to allow them to stack against curved cargo-holds. (Likewise the US military have standardised on their own "master pallet".) A Packplane type system, OTOH, would be unique to each airframe and wouldn't really save you anything in airport handling. It would just add another step to go wrong, another set of equipment to buy to move the Packplane shell around, in addition to the equipment to load the shell (ULDs/master-pallets, forklifts, etc) and support the loaded and uploaded airframe.

The launch vehicle equivalent of pallets/ULDs/ISOs would be the cubesats and their racks and launchers. If launch vehicles ever became so large that they routinely shipped dozens of full scale (say 5t) satellites in a single launch, then I suspect something like a 2.4x2.4x2.4m "cubesat" standard would evolve. (2.4m/8ft is pretty common for 3+m shrouds, 4.8m/16ft for 5.5m shrouds. Makes a nice 1U, 2U standard.)

Without that, I don't think there's a an advantage in creating a single "Packplane" payload module for a launcher. It doesn't give you "aircraft-like operations". Operationally, it just increases the handling - integrate the payload into the container, then the container into the launcher. So the container is really just wasted payload.  It's different if you were routinely trying to integrate 10-20 separate payloads into a single HLV where a size-standardised payload-rack would improve operations enough to justify the rack's mass.
« Last Edit: 03/05/2015 01:44 PM by Paul451 »

Offline RanulfC

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #147 on: 03/05/2015 02:57 PM »
Approx. 97% off-topic:

Probably closer to 98%+ but that's a quibble :)

>cut for brevity attempt :)<
Quote
The Packplane concept (and Skylon equivalent) is not analogous to ISO containers. Shipping containers are much smaller than the ships that carry them. Ditto palletised cargo that goes in a shipping container or truck box. The pallets/container are much smaller than the cargo-carrier so that you don't have to worry about the vehicle size. A 2 pallet van, a 2x2x5 pallet truck, a 2x2x10 pallet ISO shipping container...  A single 2-TEU skeleton trailer, a double-stack 2-TEU train carriage, a 36-TEU river barge, a 5,000-TEU Panamax, etc.

But there's no shipping equivalent of the Packplane, where you have a single removable module that becomes a ship's entire hold, even though ships similar to an empty Packplane exist for other purposes, so it's not a structural issue. It would be simple to design a roll-on/roll-off giant freight module for such a ship, but each semi-submersible platform-ship is a unique size, therefore each giant freight module would be bespoke to each ship. You can see where this is going...

Similarly, instead of a Packplane, the air-freight equivalent of ISO containers are the much smaller ULD containers, light pallets with corner cutaways to allow them to stack against curved cargo-holds. (Likewise the US military have standardised on their own "master pallet".) A Packplane type system, OTOH, would be unique to each airframe and wouldn't really save you anything in airport handling. It would just add another step to go wrong, another set of equipment to buy to move the Packplane shell around, in addition to the equipment to load the shell (ULDs/master-pallets, forklifts, etc) and support the loaded and uploaded airframe.

The launch vehicle equivalent of pallets/ULDs/ISOs would be the cubesats and their racks and launchers. If launch vehicles ever became so large that they routinely shipped dozens of full scale (say 5t) satellites in a single launch, then I suspect something like a 2.4x2.4x2.4m "cubesat" standard would evolve. (2.4m/8ft is pretty common for 3+m shrouds, 4.8m/16ft for 5.5m shrouds. Makes a nice 1U, 2U standard.)

Without that, I don't think there's a an advantage in creating a single "Packplane" payload module for a launcher. It doesn't give you "aircraft-like operations". Operationally, it just increases the handling - integrate the payload into the container, then the container into the launcher. So the container is really just wasted payload.  It's different if you were routinely trying to integrate 10-20 separate payloads into a single HLV where a size-standardised payload-rack would improve operations enough to justify the rack's mass.

In general I agree.

The "Packplane" concept lives a proof of the "Bee-plane" (http://www.bee-plane.com/) but the issue is the fact that you have to make each "pod" the equivalent of an aircraft fuselage no matter WHAT the cargo is. That costs. At the time the Packplane was proposed you could almost get away with a "pod" being nothing more than a cheap metal tube on some car-wheels and a roof mounted hard point attachment. All well and good but as someone who's spent a great deal of time on board NORMAL transport aircraft with minimum insulation and sound proofing, (it looks funny but you can tell the folks going home in the desert because they show up for on the flight line in thermal underwear and parkas and are happy about it :) ) while it MIGHT work for the military for normal passenger or freight services you need more structure and support. And your cost ramps up fast. Plus there is the drag and other aerodynamic issues and the fact that you "core" aircraft is ONLY usable with the pod system and in the end the effort doesn't "seem" worth it.

Note the "quotes" there :) As shown by the Bee-Plane being only the latest example the idea won't go away and really, from studies done such a "pod" system might in fact be the future of civil passenger aviation. Someday :)
But the process isn't really applicable for space flight, not anytime soon at least.

Now I've seen some concepts (and patents thereof :) ) that involve hooking together actual ISO containers either onto fuselage or making a fuselage out of them and most look pretty dodgy for "regular" use but as Paul451 notes you COULD just simple stuff ISO containers into a detachable fuselage pod and call it done but it will not BE an "ISO container" aircraft anymore than a "container" ship is made out of containers :)

Standardized "Payload" pods though could be useful and probably will be but not any time soon I think. That kind of "containerization" of cargo takes a certain level of both throughput for a transportation system AND at least some degree of "standardization" of cargo loads as well. We're not there yet with space transport as no two satellites are exactly the "same" enough to allow a single standardized payload attachment and support system.

Except as noted (again) by Paul451; cubesats.

I don't think it's too far fetched to imagine that once access frequency goes up and costs come down that a similar architecture for larger satellites won't spring up and lead to a "standardized" payload module and interfaces.

Randy
From The Amazing Catstronaut on the Black Arrow LV:
British physics, old chap. It's undignified to belch flames and effluvia all over the pad, what. A true gentlemen's orbital conveyance lifts itself into the air unostentatiously, with the minimum of spectacle and a modicum of grace. Not like our American cousins' launch vehicles, eh?

Offline Archibald

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #148 on: 03/06/2015 05:42 AM »
Quote
The Falcon-9 with the with an aeroshell that landed a folded up Blackhawk and crew/soldiers was, I thought a nice attempt at addressing the issues

WTF ??!!

Offline RanulfC

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #149 on: 03/06/2015 03:30 PM »
Quote
The Falcon-9 with the with an aeroshell that landed a folded up Blackhawk and crew/soldiers was, I thought a nice attempt at addressing the issues

WTF ??!!

Impressive :) It only took three days for someone to catch that one. Yup, was a suggested approach I read on an engineering forum. Not QUITE as crazy as it sounds but not far off :)

Randy
From The Amazing Catstronaut on the Black Arrow LV:
British physics, old chap. It's undignified to belch flames and effluvia all over the pad, what. A true gentlemen's orbital conveyance lifts itself into the air unostentatiously, with the minimum of spectacle and a modicum of grace. Not like our American cousins' launch vehicles, eh?

Offline tea monster

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #150 on: 03/06/2015 06:13 PM »
Wow! Lock, n load, n launch soldier!

It would be great to be the only helo pilots on the planet with astronaut's wings!  ;)

Offline Archibald

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #151 on: 03/08/2015 07:52 AM »
Quote
The Falcon-9 with the with an aeroshell that landed a folded up Blackhawk and crew/soldiers was, I thought a nice attempt at addressing the issues

WTF ??!!

Impressive :) It only took three days for someone to catch that one. Yup, was a suggested approach I read on an engineering forum. Not QUITE as crazy as it sounds but not far off :)

Randy

Do you have a link to that "engineering forum" ?

Offline tatarana

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #152 on: 03/10/2015 11:05 PM »
As was said several times in this and the previous 4 threads, SABRE engine seems to scale down badly due to problems with the LH2 pump.
BUT... ???
What are the perspectives to scale it up, if (normal size) SABRE and Skylon fulfill its promises ?
There would be any limits to build a larger Skylon to send heavier payloads to orbit,
as for example, doubling payload to 30 tonnes ? An obvious one is the runway reinforced concrete pavement, but there are any fundamental limits ?
Also, what would be  possible economic reasons to scale it up ?

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Offline 93143

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #153 on: 03/11/2015 03:19 AM »
http://forum.nasaspaceflight.com/index.php?topic=24621.msg735577#msg735577

Quote from: Hempsell
We have not seriously explored taking the SKYLON type vehicle up to the heavy lift class but the few “fun exercises” we have done have not shown any fundamental upper limit technically but the economics go to pot. Basically making the systems as small as possible while still capturing the main market (i.e. not small sats) throws the economic burden on to more launches (where reusables score) and off development cost and acquisition cost (where reusable suffer).

If the market for large payloads gets to the point where a bigger vehicle makes sense, someone will design one.  Kinda like how locks on the St. Lawrence Seaway have been replaced with bigger ones multiple times as shipping outgrew them.

Alternately, if someone with big plans and deep pockets decides they want a super heavy Skylon-type vehicle for their own purposes, they might pay to get one built; NASA and SpaceX are both doing this already with more conventional launcher technology.
« Last Edit: 03/11/2015 03:31 AM by 93143 »

Offline john smith 19

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #154 on: 03/12/2015 10:05 PM »
If the market for large payloads gets to the point where a bigger vehicle makes sense, someone will design one.  Kinda like how locks on the St. Lawrence Seaway have been replaced with bigger ones multiple times as shipping outgrew them.
Interesting analogy.

It's an interesting point that those locks were the right size for the bulk of the traffic at the time they were built, but really big ships would have to take the long way round.

Skylon won't deliver the biggest payloads to orbit but it will deliver the bulk of payloads. Will that matter? Time will tell.
"Solids are a branch of fireworks, not rocketry. :-) :-) ", Henry Spencer 1/28/11  Averse to bold? You must be in marketing."It's all in the sequencing" K. Mattingly.  STS-Keeping most of the stakeholders happy most of the time.

Offline tatarana

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #155 on: 03/14/2015 03:40 PM »
http://forum.nasaspaceflight.com/index.php?topic=24621.msg735577#msg735577

Quote from: Hempsell
We have not seriously explored taking the SKYLON type vehicle up to the heavy lift class but the few “fun exercises” we have done have not shown any fundamental upper limit technically but the economics go to pot. Basically making the systems as small as possible while still capturing the main market (i.e. not small sats) throws the economic burden on to more launches (where reusables score) and off development cost and acquisition cost (where reusable suffer).

If the market for large payloads gets to the point where a bigger vehicle makes sense, someone will design one.  Kinda like how locks on the St. Lawrence Seaway have been replaced with bigger ones multiple times as shipping outgrew them.

Alternately, if someone with big plans and deep pockets decides they want a super heavy Skylon-type vehicle for their own purposes, they might pay to get one built; NASA and SpaceX are both doing this already with more conventional launcher technology.

93143, thanks a lot for the refresher.  During  thread 1  I was still not able to follow the subtle points of arguments about space markets.  Skylon threads also have this nice characteristic of being a teaching tool.

JS19, your argument about 'bulk cargo' makes a lot of sense.
Question: if you take out the satellite market, what other bulk cargo could there be? Fuel to depots ?
Space station's construction components by other nations ?

Some time ago I read a nice paper about space mining, NEAR EARTH OBJECTS AS RESOURCES FOR SPACE INDUSTRIALIZATION, by MARK SONTER. He makes a strong argument by examining and comparing the mining industry on Earth with space use. One of his conclusions was that it could be possible to build a space craft mining unity that would weight something like 5 metric tonnes. I wonder if something like this could be crammed inside a Skylon  standard cargo module, perhaps with a suplementary deep space propulsion unit launched separately (perhaps  electric propulsion like Vasimr, that uses argon and hydrogen that could be mined and replenished  in situ). This subject has ever surfaced on Skylon threads ?

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Offline john smith 19

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #156 on: 03/14/2015 04:59 PM »
JS19, your argument about 'bulk cargo' makes a lot of sense.
Question: if you take out the satellite market, what other bulk cargo could there be? Fuel to depots ?
Space station's construction components by other nations ?
Welcome to the site.

In hindsight "bulk" might not have been the best word. Certainly Skylon can cover the majority of the known and expected payload growth in those known markets. That said the aggregate mass these missions put up easily exceed any single payload over time.

Actual bulk payloads are either things that need to be delivered in large volumes (or masses) or that cannot be sub divided. The former would be propellants, water, toilet tissue, ready meals. The latter would be things like large nuclear reactors or telescopes.

REL have done various studies to ensure that their vehicle can accommodate tasks as diverse as launching satellites to GEO, probes to other planets and their moons (while retaining the upper stage) and full blown Mars missions.

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Some time ago I read a nice paper about space mining, NEAR EARTH OBJECTS AS RESOURCES FOR SPACE INDUSTRIALIZATION, by MARK SONTER. He makes a strong argument by examining and comparing the mining industry on Earth with space use. One of his conclusions was that it could be possible to build a space craft mining unity that would weight something like 5 metric tonnes. I wonder if something like this could be crammed inside a Skylon  standard cargo module, perhaps with a suplementary deep space propulsion unit launched separately (perhaps  electric propulsion like Vasimr, that uses argon and hydrogen that could be mined and replenished  in situ). This subject has ever surfaced on Skylon threads ?
The current Skylon revision is for a payload of 15 tonnes in a payload bay about 13m long and close to 5m in diameter. It's not that cramped, although the price would be set by the Skylon operators.

It should be big enough to accommodate such a payload.
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Offline francesco nicoli

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #157 on: 03/15/2015 09:57 PM »
the issue with Skylon and asteroids mining is actually that miners expect to get most of their initial revenue from basic commodities, like water, which value per kg in space equals their launching cost per kg.

Skylon kills this business case by providing cheap access. it brings the value of water down from 14k $ per kilo, to 600 $ per kilo.

Offline Hanelyp

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #158 on: 03/16/2015 04:44 AM »
But bringing down launch costs also brings down the expense to deploy asteroid mining equipment.

Offline Paul451

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #159 on: 03/16/2015 06:35 AM »
Skylon kills this business case by providing cheap access. it brings the value of water down from 14k $ per kilo, to 600 $ per kilo.

Bringing down the cost of access to LEO increases the number of users who can justify access, which increases the number of users who can then justify BEO missions. (Even if its primarily university/govt research.) That creates a much larger initial market for water/air/fuel delivered to BEO facilities from local sources. That then lowers the cost of operations BEO, and increases the number of users who can justify going a step further out.

Additionally, the increase in users in LEO and BEO pays for the development of more HSF and robotic technology. That lowers the start-up cost for asteroid (and lunar-pole/Mars moons/etc) miners.

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