Author Topic: The Reaction Engines Skylon Master Thread (5)  (Read 421870 times)

Offline Robotbeat

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #880 on: 11/25/2015 12:36 AM »
When, if ever, will Skylon fly? Anyone want to put down a prediction?
1st flight.

8 years after full funding starts with the current plan.

5 years if they can manage to launch a zero payload demonstrator that flies the whole mission with their existing funding and the rest of the world "discovers" that it works as described.
I meant an actual year.

It's likely that even if it flies, it will never get "full funding" until it's basically flying.

Anyone have a year?
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0

Offline Elmar Moelzer

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #881 on: 11/25/2015 12:53 AM »
One capability that could command a fat check from deep defense coffers is anywhere/anytime rapid reconnaissance.
Isn't it sad that military is getting so much more funding that space flight that we have to go look there for "fat checks"?

Offline 93143

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #882 on: 11/25/2015 12:58 AM »

Offline Robotbeat

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #883 on: 11/25/2015 01:44 AM »
Anyone have a year?

Why?
Just wondering. I find it useful when people passionate about a thing (myself included) actually put down their opinion numerically, mark their beliefs to market, as it were.
« Last Edit: 11/25/2015 01:45 AM by Robotbeat »
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0

Offline john smith 19

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #884 on: 11/25/2015 06:35 AM »
Anyone have a year?

Why?
Just wondering. I find it useful when people passionate about a thing (myself included) actually put down their opinion numerically, mark their beliefs to market, as it were.
What a good idea.

What were your dates for when SX would recover it's first F9 booster? BFR flight? MCT flight?
I'm curious

I'll note that Musk said of the crew escape system on Dragon 2.0 "3 years once we get full funding."
"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 john smith 19

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #885 on: 11/25/2015 06:36 AM »
A quick tangent on military applications for REL/Skylon. One capability that could command a fat check from deep defense coffers is anywhere/anytime rapid reconnaissance.
Only if a government issues a request for it. Defense contractors don't buy stuff unless a government has already paid them (much more) for it.
Quote
I was thinking that Skylon could be good for this, but I've just read that the Falcon F9R-FT first stage is supposedly capable of SSTO, i.e. when carrying no second stage or payload+fairing. If it could manage to heft cameras etc., then that could give you overflight imagery of anywhere in less than ~30 minutes. Skylon would have one advantage over the Falcon, however: it wouldn't look exactly like a pre-emptive ICBM launch.  :o
"Anywhere" provided it's at a 28 deg slant to the equator or within the plane change range of an F9. Incidently you're confusing SSTO with reusability.

What (I think) you're thinking about is an SSTO and landing for reuse. That still gives you all the orbital velocity and therefore all the problems SX say make 2nd stage reuse "uneconomic"
so won't happen.
Quote
Disclaimer: I've no idea if the SSTO claims for F9 S1 are true, or if it's capable of doing a once-around, or re-entering from orbital speed. The point is simply that while a Skylon could be useful for reconnaissance, there could be other, cheaper options available to military planners.
Given the excellent mass fraction of the booster, and the fact it's got a GNC package on board to do barge landings if you didn't install the landing legs and grid fins (and the ETL can carry a single stage rigidly) then yes an expendable SSTO with some payload seems pretty credible.
« Last Edit: 11/25/2015 06:38 AM by john smith 19 »
"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 adrianwyard

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #886 on: 11/25/2015 07:49 AM »
Incidently you're confusing SSTO with reusability.

Nope.

I was thinking of the sort of mission USAF wanted from Shuttle, so sufficient cross range to get home in a single orbit is needed, and no small feat.

And to be fair you should mention that Falcon Stage 2 reusability is harder because it typically returns from geostationary transfer orbit.

But my point was not to argue that Elon can sell a Spy Falcon to USAF, but that it's darned difficult to find applications for Skylon that are uniquely compelling other than satellite launch. Others here think there military applications could help get the thing built, and i was exploring that.

Offline 93143

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #887 on: 11/25/2015 08:36 AM »
And to be fair you should mention that Falcon Stage 2 reusability is harder because it typically returns from geostationary transfer orbit.

That's not the only reason.  It's what makes it so hard that Elon said he wouldn't even try.

Regardless, I don't see why safe reentry is necessary, any more than a modern spy satellite has to drop film canisters.

Quote
it's darned difficult to find applications for Skylon that are uniquely compelling other than satellite launch.

Most of what was uniquely useful about STS is also possible with Skylon, which is almost certain to be vastly cheaper.
« Last Edit: 11/25/2015 08:48 AM by 93143 »

Offline lkm

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #888 on: 11/25/2015 12:13 PM »
Anyone have a year?

Why?
Just wondering. I find it useful when people passionate about a thing (myself included) actually put down their opinion numerically, mark their beliefs to market, as it were.

I've thought for a while that REL has an 80% chance they get a working engine built by 2020 but only a 40% chance they can get a consortium put together to build Skylon.
Should that consortium be built I see an IOC of Skylon in a possible range between 2028 -2032 with 2030 most likely. An IOC of 2028 means that the ISS could still be used as part of the testing programmes and is only 3 years late based off their last published programme schedule and is in the middle of Mark Thomas's 10-15 years. However the BAE deal and the numbers that came with it make me more pessimistic on schedule.
Generally when the Skylon launch market is being discussed I'm thinking 2030 so I'll pick that, with the provisos that I think there's only a 40% chance of the consortium at all. 

Offline john smith 19

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #889 on: 11/25/2015 01:58 PM »

Nope.

I was thinking of the sort of mission USAF wanted from Shuttle, so sufficient cross range to get home in a single orbit is needed, and no small feat.
Basically that was the theft of a Russian satellite.

An item that would have either happened during WWIII or started WWIII.

The technical description for this was insane.

As it happens I think REL have indicated Skylon and the SABRE 4 cycle would give this capability (or very close to it) as it just has much better aerodynamics than Shuttle.
Quote
And to be fair you should mention that Falcon Stage 2 reusability is harder because it typically returns from geostationary transfer orbit.

But my point was not to argue that Elon can sell a Spy Falcon to USAF, but that it's darned difficult to find applications for Skylon that are uniquely compelling other than satellite launch. Others here think there military applications could help get the thing built, and i was exploring that.
Which could be said of all launch vehicles.

"Military applications" of Skylon are basically putting military payloads into orbit.

If you want reusability and fast turnaround IE "responsive space" as the military tend to call it, then Skylon can deliver it to military customers, as it can to all customers.

"Weaponizing" a Skylon is plot for a straight-to-download thriller.

If  you've got those skills and that funding you can cause a lot more mayhem a lot more cheaply.  :(
"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 Hanelyp

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #890 on: 11/25/2015 03:31 PM »
A quick tangent on military applications for REL/Skylon. One capability that could command a fat check from deep defense coffers is anywhere/anytime rapid reconnaissance. ...
Presuming a minimal altitude good for only a modest number of orbits, how much payload is Skylon expected to be capable of lifting to a high inclination orbit?  If enough for a good telescope in the payload bay it might offer overflights of a target of urgent interest on shorter notice than the SR-71 did.  A peripheral question to such an operation is how willing and able would the target of such an overflight be to shoot at the spacecraft?

Offline adrianwyard

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #891 on: 11/25/2015 03:39 PM »
"Weaponizing" a Skylon is plot for a straight-to-download thriller.
If  you've got those skills and that funding you can cause a lot more mayhem a lot more cheaply.  :(

I agree.

Most of what was uniquely useful about STS is also possible with Skylon, which is almost certain to be vastly cheaper.

Also agree. But we're back at the classic chicken-and-egg problem for Skylon: if money and politics were no obstacle then I'm confident we'd be reaping the benefits of Skylon launchers in the near term future - including STS-style capabilities and low launch prices. But realistically, how can the political and financial case be made?

In a different universe where there were no other credible projects that could potentially reduce launch costs through re-use, Skylon would surely attract attention from investors. And similarly, if SLS were not looking like it could actually fly then large-scale space projects could be enabled via multiple cheap Skylon launches, autonomous docking, and fuel depots, etc. And if the Ariane-6 procurement had been a bit later... Etc., etc.

Please don't misunderstand my gloomy comments, I want to believe there's a way to get Skylon financed and built, but need some help staying optimistic. Anyone?

Offline lkm

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #892 on: 11/25/2015 08:42 PM »


In a different universe where there were no other credible projects that could potentially reduce launch costs through re-use, Skylon would surely attract attention from investors.

If there were no other credible projects that could potentially reduce launch costs through re-use why would anyone need to invest in it?  If SpaceX or Blue Origin lowers launch costs through reuse is Boeing going to just exit the launch market or are they going to invest in reuse? Is Airbus just going to exit the launch market or are they going to invest in reuse?
The only launch provider that can launch Falcon is SpaceX, the only launch provider that can launch New Shephard is Blue Origin for everybody else there's what? Well if they care to invest there's Skylon, which every launch provider can buy.
There's 14 active launch service providers globally, only one of which is SpaceX. In a potential age of reusable launch they all have to be launching something competitive or go out of business.
« Last Edit: 11/25/2015 10:47 PM by lkm »

Offline 93143

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #893 on: 11/25/2015 09:43 PM »
Presuming a minimal altitude good for only a modest number of orbits, how much payload is Skylon expected to be capable of lifting to a high inclination orbit?

User's Manual v2.1 says a little over 8 tonnes to 160 km sun-synch, given a launch site at 30.

Offline Robotbeat

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #894 on: 11/25/2015 11:25 PM »
Anyone have a year?

Why?
Just wondering. I find it useful when people passionate about a thing (myself included) actually put down their opinion numerically, mark their beliefs to market, as it were.
What a good idea.

What were your dates for when SX would recover it's first F9 booster? BFR flight? MCT flight?
I'm curious

I'll note that Musk said of the crew escape system on Dragon 2.0 "3 years once we get full funding."
Irrelevant and off-topic, but yes, I did mark down my predictions to market. Not sure about BFR/MCT, but there was a thread for voting on F9 booster recovery that I voted in.

No need to be defensive nor to change the topic to SpaceX.
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To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0

Offline adrianwyard

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #895 on: 11/26/2015 12:44 AM »


In a different universe where there were no other credible projects that could potentially reduce launch costs through re-use, Skylon would surely attract attention from investors.

If there were no other credible projects that could potentially reduce launch costs through re-use why would anyone need to invest in it?  If SpaceX or Blue Origin lowers launch costs through reuse is Boeing going to just exit the launch market or are they going to invest in reuse? Is Airbus just going to exit the launch market or are they going to invest in reuse?
The only launch provider that can launch Falcon is SpaceX, the only launch provider that can launch New Shephard is Blue Origin for everybody else there's what? Well if they care to invest there's Skylon, which every launch provider can buy.
There's 14 active launch service providers globally, only one of which is SpaceX. In a potential age of reusable launch they all have to be launching something competitive or go out of business.

I think you've succeeded in laying out a hopeful and plausible scenario for Skylon. It just involves waiting a number years. IIUC the story goes something like:

1] By ~2020, REL have a working development engine, AND SpaceX are undercutting the competition by reaping the rewards of their reusable first stage.

2] Faced with either paying high prices for expendable launchers, or ceding the launch market to SpaceX (and Blue?) interested parties band together and form a consortium which cumulatively has the financial clout and risk capacity to complete a next generation vehicle that can compete with SpaceX.

Now that semi-reuse has been demonstrated there is a desire to skip a generation ahead of the competition, and Skylon fits the bill as a fully reusable SSTO. Hopefully Franscesco's timeline of orbital testing in 2028 could still be kept.

Such a scenario is dependent as much on geopolitical/financial realities as the rocket equation, but who knows - perhaps such as consortium could be assembled. There are precedents: Concorde, the Channel Tunnel, and of course the ISS come to mind. Even Ariane.

Viewing the problem this way does prompt some interesting new questions: For example, the Russians and Chinese have not put much energy into re-use thus far. Their indigenous expendable programs are surely expensive, and there must be some pressure internally to find more cost-effective ways to launch commercial/civilian payloads.

Such a consortium would need to be truly multinational - so no one put RAF roundels on the wings  ;).

And we'd likely see parts of development farmed out to member countries Ariane-style.

Or perhaps if we stretch the timeline out to where ESA is looking beyond Ariane 6, it could just be Ariane 7.
« Last Edit: 11/26/2015 12:46 AM by adrianwyard »

Offline Robotbeat

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #896 on: 11/26/2015 12:50 AM »
I would love that kind of scenario. It's been too long before we've seen some real fight by foreign launch providers on the technology front.
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Offline RonM

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #897 on: 11/26/2015 01:07 AM »
Such a consortium would need to be truly multinational - so no one put RAF roundels on the wings  ;).

Oh, I was so looking forward to a Queen's Own Skylon Squadron.  :)

I would love that kind of scenario. It's been too long before we've seen some real fight by foreign launch providers on the technology front.

Yes, Europe needs to get into the fight on the technology front.

Offline Oli

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #898 on: 11/26/2015 02:04 AM »
Now that semi-reuse has been demonstrated

Semi-reuse has been demonstrated 35 years ago.

New Shepard is designed for suborbital tourism, that's a market that could potentially support a very high flight rate. No such market will exist for orbital spaceflight anytime soon (i.e. decades), and whether Skylon could create that market is very uncertain at best.

Why does REL not design an engine for suborbital tourism? I don't understand REL's obsession with SSTO, it sometimes makes me question whether their technology is ready for reality.


Offline tl6973

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Re: The Reaction Engines Skylon Master Thread (5)
« Reply #899 on: 11/26/2015 08:35 AM »
Why does REL not design an engine for suborbital tourism? I don't understand REL's obsession with SSTO, it sometimes makes me question whether their technology is ready for reality.

Because there is no need for a complex new engine class for suborbital flight

you can easily achieve this using legacy rocket technology

you can get a fair way to achieving it with jet engines alone: a MiG-25M got to 123,500ft, in 1977

In fact, do you even need an engine at all? http://worldviewexperience.com/voyage/#flight-profile

Sub-orbital flight is about going up (100km),  moderately fast (M3), for a bit

Orbital flight is about going insanely fast (M25), moderately up (150km +)

The fast is much much harder than the up, which is why SABRE is important for Orbital flight but unnecessary for suborbital flight

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