The Reaction Engines Skylon Master Thread (1)

[Jim]

Spacex is flying and making money

Didn't the buggy whip manufacturers say something similar when the horseless carriage came out? It's not just Esa that needs to start worrying about Ariane. If SKYLONs can service the ISS, SpaceX might find the gravy train ending.

Not the same thing.  Horseless carriages were already on the road.  Skylon hasn't passed the equivalent to an IC engine running on a bench yet. 

Anyways,
a.  who would be operating the Skylons servicing the ISS
b.  ISS servicing is only a stepping stone for Musk.  He wants to go further than LEO in bigger pieces than 15 tons.
c.  The ISS will be near its end by the time Skylon is on the market.
d.  What says Skylon will not go the way of HOTOL, Space Shuttle, Concorde or SR-71?

[flymetothemoon]

d.  What says Skylon will not go the way of HOTOL, Space Shuttle, Concorde or SR-71?

Talk about comparing apples, pears, oranges and bananas! 

[Elmar Moelzer]

I think that part of the appeal of the engine technology are its terrestrial uses. They are planning to license the technology to 3rd parties that will probably quickly develop it further.
Their technology is supposed to generally make jet planes more fuel efficient and it would allow hypersonic flight. Hypersonic flight might not necessarily have to be cost effective for civilians, but I can see a few generals rubbing their hands in delight at the prospect of mach5 jets
So licensing the tech to manufacturers of military jets will mean big money.
They also claim some uses for desalination, which might add to the long term revenue.

[Jim]

d.  What says Skylon will not go the way of HOTOL, Space Shuttle, Concorde or SR-71?

Talk about comparing apples, pears, oranges and bananas! 

No, they are very relevant.  The point is that they were technically feasible but not economically
Anyways, they are all more relevant than buggy whips to this conversation.

[Longstaff]

Spacex is flying and making money

Didn't the buggy whip manufacturers say something similar when the horseless carriage came out? It's not just Esa that needs to start worrying about Ariane. If SKYLONs can service the ISS, SpaceX might find the gravy train ending.

Not the same thing.  Horseless carriages were already on the road.  Skylon hasn't passed the equivalent to an IC engine running on a bench yet. 

Anyways,
a.  who would be operating the Skylons servicing the ISS
b.  ISS servicing is only a stepping stone for Musk.  He wants to go further than LEO in bigger pieces than 15 tons.
c.  The ISS will be near its end by the time Skylon is on the market.
d.  What says Skylon will not go the way of HOTOL, Space Shuttle, Concorde or SR-71?

a: any operator who could undercut the competition with a lower launch price
b: anything can be packaged into 15 tonne payloads (see project TROY on REL website)
c: correct, but will it be the last one, or can its' life be economically extended?
e: nothing at all, except that my local pub (as a youth) was the one that produced Locomotion No. 1 (did that ever lead to anything?)

[Rugoz]

d.  What says Skylon will not go the way of HOTOL, Space Shuttle, Concorde or SR-71?

If you forget about dev. costs skylon will probably be cheap and profitable.
I only question that private investors alone will realize it for the commercial market. Remember just because skylon will be cheaper doesn't mean military/gov/nasa/esa etc. will suddenly outsource their launches to a private company.

[Jim]

doesn't mean military/gov/nasa/esa etc. will suddenly outsource their launches to a private company.

The US military and NASA already do

[Elmar Moelzer]

Not the same thing.  Horseless carriages were already on the road.  Skylon hasn't passed the equivalent to an IC engine running on a bench yet. 

Anyways,
a.  who would be operating the Skylons servicing the ISS
b.  ISS servicing is only a stepping stone for Musk.  He wants to go further than LEO in bigger pieces than 15 tons.
c.  The ISS will be near its end by the time Skylon is on the market.
d.  What says Skylon will not go the way of HOTOL, Space Shuttle, Concorde or SR-71?

I think that it is very likely that there will be lots of other orbital destinations (like Bigelows spacestations) by the time Skylon comes online.
Plus the market will grow when the price to orbit goes down.

[BobCarver]

My point is that Elon is taking the traditional path, but needs to be more up-to-date on the competition down the road. It's not prudent to think that being the lowest-cost launcher today will always be the case. An expendable rocket built from a clean sheet to operational is quite an accomplishment, but it's expendable after all. It has been successful in lowering launch costs by a substantial amount. But, SKYLON is a competitor and needs to be factored into the cost equation as well. Reusable Falcon could compete very effectively. We might have a two-party race on our hands (I cheer for both parties myself), SKYLON vs. reusable Falcon.

We have confirmation that the biggest technical hurdle for SKYLON is passed now. It's time to bend metal. And, in fact, I think that may be the next biggest technical hurdle for SKYLON: embrittlement of the hydrogen fuel tanks and plumbing. When metal bends, it forms spaces in the lattice which hydrogen atoms can migrate into and cause embrittlement. This could be a big problem for reusability and I don't know whether REL has really addressed it. They need to find a way to get helium into the equation to fill the spaces before the hydrogen damages it.

[Jim]

Plus the market will grow when the price to orbit goes down.

Words that have been repeated for the last 40 years.

[QuantumG]

Folks, the conjunction you are looking for is "if", not "when".

Same goes for talking about the reusable vehicles from SpaceX, or even the Falcon Heavy.

None of 'em are flying yet and none of us have a crystal ball.

[Jim]

We might have a two-party race on our hands (I cheer for both parties myself), SKYLON vs. reusable Falcon.

And yet could not be a race at all, and ELV's still dominate the market.

[Elmar Moelzer]

Words that have been repeated for the last 40 years

Maybe that's because the price to orbit has not gone down for 40 years?
It has been proven for airflight, I would even claim that it has been proven even for suborbital flight.
Why would it be any different for orbital flight?

[93143]

To break even they have to make 1.8171b profit every year for 10 years.

In other words, they have to sell two Skylons per year to make a profit.

How long it takes the purchasers to churn through the advertised 200 flights per airframe is beside the point.

b: anything can be packaged into 15 tonne payloads (see project TROY on REL website)

Literally anything?

I could fairly easily think of a few things that would be quite a bit more difficult to assemble on orbit than on the ground.  And if we're talking about Skylon vs. fully-reusable MCT, the cost advantage of Skylon could be small or worse.

Words that have been repeated for the last 40 years

Maybe that's because the price to orbit has not gone down for 40 years?

It has.  The problem is that it hasn't gone down far enough.  The market is still inelastic at these prices:

http://forum.nasaspaceflight.com/index.php?topic=20857.msg562340;topicseen#msg562340

[Jim]

Words that have been repeated for the last 40 years

Maybe that's because the price to orbit has not gone down for 40 years?
It has been proven for airflight, I would even claim that it has been proven even for suborbital flight.
Why would it be any different for orbital flight?

Suborbital is still unproven.
As far as airflight, was Mach 2 service? no.

Orbital flight requires large amounts of contained energy at high velocity with small margins.

[Elmar Moelzer]

That hasn't yet either.

Sure it has, just look at the preorders for suborbital rides! That is already waaay more than critics like you ever would have believed. I am sure it will be even more once these things actually start flying.

In other words, they have to sell two Skylons per year to make a profit.

Nope, since there are other uses for the technology than Skylons that will mean a secondary stream of income for the company.

The problem is that it hasn't gone down far enough.  The market is still inelastic at these prices

I have my doubts about that.

[Elmar Moelzer]

Suborbital is still unproven.

Not it is not unproven!

As far as airflight, was Mach 2 service? no.

irrelevant!
The Mach2 flight was too little an improvement for the cost.

Orbital flight requires large amounts of contained energy at high velocity with small margins.

irrelevant to the question whether the market will react to lower prices.

[93143]

In other words, they have to sell two Skylons per year to make a profit.

Nope, since there are other uses for the technology than Skylons that will mean a secondary stream of income for the company.

Those are likely to be further down the road, and may depend on getting the cost of the heat exchangers down a bit.

The problem is that it hasn't gone down far enough.  The market is still inelastic at these prices

I have my doubts about that.

Follow the link.  There's a graph attached.

In 1994, the market was inelastic above $800/lb.  Both Skylon and reusable Falcon are expected to get below that, assuming all goes as planned, but we aren't anywhere near there yet.

Granted there have been more changes in the aerospace sector since 1994 than just inflation, but I think the same general principles apply, and the number is likely good as a ballpark estimate.

[Elmar Moelzer]

Those are further down the road, and may depend on getting the cost of the heat exchangers down a bit

From what I understand, they are going to license this to 3rd parties as soon as they have it. That should mean money pretty much right away.

Follow the link.  There's a graph attached.

Yeah, I saw it and I doubted the graph. Who makes these statistics?
Probably the same people on wallstreet that gave us the financial crisis.

Its why Burt Rutan called NASA "NaySay". This sort of conservative thinking has not gotten us anywhere in 30 years.

[WellingtonEast]

Hi,

A query about the discussion on the need not to fly supersonic over land.

On the Nasa site
http://www.nasa.gov/centers/dryden/news/FactSheets/FS-016-DFRC.html

It states that

"Overpressures of 1 to 2 pounds are produced by supersonic aircraft flying at normal operating altitudes. Some public reaction could be expected between 1.5 and 2 pounds."


It then provides a list of typical overpressure per aircraft types at varying height levels:

SR-71:             0.9 pounds, speed of Mach 3, 80,000 feet
Concorde SST: 1.94 pounds, speed of Mach 2, 52,000 feet
F-104:             0.8 pounds, speed of Mach 1.93, 48,000 feet


In this context if Skylon is flying at 25KM = 80,000 feet for intercontinental trips - isnt the sonic boom a non issue until landing approaches where it would slow subsonic near populated areas at low altitudes??