The Reaction Engines Skylon Master Thread (1)

[lkm]

According to the Reaction Engines development plan when the Skylon enters regular commercial service in 2020 two prototype Skylons will already have conducted 300-400 flights over two years and will have conducted every possible mission plan at least four times including 16 visits to the ISS 4 of which will deliver crew. That's potentially nearly 90mt and 16 crew.
They intend for a parallel development of the main initial Skylon specific payloads, in time for the flight test program, of the Skylon Upper Stage, the Skylon Passenger/ Logistics Module, the Skylon Small Payload Carrier and the Skylon Orbiting Facility Interface.
The SUS can put a 8.25mt payload into GTO in expendable mode or 6.25mt in reusable mode and has a notional unit cost of $65m(2009).
The SPLM can put up to 24 people in LEO or 3mt of cargo or combination thereof and has a notional unit cost of $75m(2009).

A Skylon can deliver 1.5mt more to GTO than a Falcon 9 at a cheaper price.
Skylon will enter service with more completed flight than any other launch vehicle.
Well that's the plan.

[mr. mark]

two prototype Skylons will already have conducted 300-400 flights over two years

That's the biggest bunch of, I don't know, I have ever heard. 300 - 400 launches in two years? LMOL What kind of junk are these people smoking? That would be a launch every other day! There's not enough payloads in the entire commercial catalog to justify so many launches. Cheaper than Falcon 9 really? When you compare total development costs and add them in, I'm sure the picture will look completely different. The Skylon project managers should be subject to a mental evaluation if they actually believe this.

[Robotbeat]

If you're going to do rapid reusability, do rapid reusability.

XCOR has already demonstrated rapid reuse of a rocket plane, with something like 9 flights in a day, etc. Obviously the performance was NOTHING compared to an orbital craft, but the same concept still applies.

I sort of doubt that Skylon will be the cheapest and am skeptical that they aren't running on razor-thin margins somewhere (sure they CLAIM they have lots of margin), but this is the right concept of operations, IMHO.

[mr. mark]

Rapid reuse is only good if you have enough satellite business to launch that many missions. 300 -400 missions is just laughable. Unlike the suborbital companies, Skylon will not be taking people on joyrides.

[Robotbeat]

Rapid reuse is only good if you have enough satellite business to launch that many missions. 300 -400 missions is just laughable. Unlike the suborbital companies, Skylon will not be taking people on joyrides.

Reliability and safety are incredibly important. If all you have to do is gas-and-go, then 300-400 missions is NOT laughable. Spending a billion dollars in fuel to demonstrate absolutely unbeatable reliability is not a bad plan.

XCOR plans to do 100 flights before taking paying customers, as well.

This is completely different from the concept of operations of munitions and expendables. This is relatively normal for initial operational tests for a large jet aircraft.

[aga]

as i understand it, it is development plan - if i should guess i would say this means that these 300-400 flights will be without payload mostly... as test flights or so...

then, if i remember correctly, REL plans to sell skylons, not to operate them...

btw:
i am no expert, but i think for any reusability you need some minimal number of flights (much more than any launcher today) - is this thought of mine correct?
then why falcon's reusability is okay and skylon's is not?

[lkm]

Rapid reuse is only good if you have enough satellite business to launch that many missions. 300 -400 missions is just laughable. Unlike the suborbital companies, Skylon will not be taking people on joyrides.

That's the flight test program, not a launch program. Each Skylon  is meant to be qualified for 200 flights and two day turn arround, so they have to fly at least one two hundred times and they can do that inside of two years. They're not carrying any payload other than a sensored test payload for most of them.

[flymetothemoon]

two prototype Skylons will already have conducted 300-400 flights over two years

That's the biggest bunch of, I don't know, I have ever heard. 300 - 400 launches in two years? LMOL What kind of junk are these people smoking? That would be a launch every other day! There's not enough payloads in the entire commercial catalog to justify so many launches. Cheaper than Falcon 9 really? When you compare total development costs and add them in, I'm sure the picture will look completely different. The Skylon project managers should be subject to a mental evaluation if they actually believe this.

http://www.reactionengines.co.uk/skylon_dev.html

Would you like to share your proposed flight test plan for an orbital vehicle that is built to fly to and from orbit several times a week?

Rapid reuse is only good if you have enough satellite business to launch that many missions. 300 -400 missions is just laughable. Unlike the suborbital companies, Skylon will not be taking people on joyrides.

What kind of reasoning concludes Skylons would not be taking people on joyrides?

They intend for a parallel development of [...] the Skylon Passenger/ Logistics Module

Very, very rich people take rides to orbit with the Russians right now.

Further reading:
http://en.wikipedia.org/wiki/Skylon_(spacecraft)

[flymetothemoon]

According to the Reaction Engines development plan when the Skylon enters regular commercial service in 2020 two prototype Skylons will already have conducted 300-400 flights over two years and will have conducted every possible mission plan at least four times including 16 visits to the ISS 4 of which will deliver crew. That's potentially nearly 90mt and 16 crew.
They intend for a parallel development of the main initial Skylon specific payloads, in time for the flight test program, of the Skylon Upper Stage, the Skylon Passenger/ Logistics Module, the Skylon Small Payload Carrier and the Skylon Orbiting Facility Interface.
The SUS can put a 8.25mt payload into GTO in expendable mode or 6.25mt in reusable mode and has a notional unit cost of $65m(2009).
The SPLM can put up to 24 people in LEO or 3mt of cargo or combination thereof and has a notional unit cost of $75m(2009).

A Skylon can deliver 1.5mt more to GTO than a Falcon 9 at a cheaper price.
Skylon will enter service with more completed flight than any other launch vehicle.
Well that's the plan.

Hi lkm again.

I am sure you are aware that these are very old figures based on the C1 configuration. The wikipedia entry is my latest info and refers to the C2 config of 15,000kg. I understood C2 could carry 40 in the passenger module (SPLM). Clearly all modules would change with a revised config too. Hence a larger SUS could be launched etc.

I remember reading REL say that they do not want to release any 'D' configuration info until it is finalised. Hence all the info on the website pertains to earlier 'C' revisions. I think they last said D config is well advanced, but they are still finalising some details.

I am hoping Baldusi will see this response and let us know anything more about the 'D4' 20 ton revision?  Do you have any links? Thanks.

Here's my 2 second effort to extrapolate how many might be carried in a Skylon capable of a 20 ton SPLM:

40 x 20/15 = 53 passengers.

Apologies if my figures are awry. I am working from memory!

[lkm]

According to the Reaction Engines development plan when the Skylon enters regular commercial service in 2020 two prototype Skylons will already have conducted 300-400 flights over two years and will have conducted every possible mission plan at least four times including 16 visits to the ISS 4 of which will deliver crew. That's potentially nearly 90mt and 16 crew.
They intend for a parallel development of the main initial Skylon specific payloads, in time for the flight test program, of the Skylon Upper Stage, the Skylon Passenger/ Logistics Module, the Skylon Small Payload Carrier and the Skylon Orbiting Facility Interface.
The SUS can put a 8.25mt payload into GTO in expendable mode or 6.25mt in reusable mode and has a notional unit cost of $65m(2009).
The SPLM can put up to 24 people in LEO or 3mt of cargo or combination thereof and has a notional unit cost of $75m(2009).

A Skylon can deliver 1.5mt more to GTO than a Falcon 9 at a cheaper price.
Skylon will enter service with more completed flight than any other launch vehicle.
Well that's the plan.

Hi lkm again.

I am sure you are aware that these are very old figures based on the C1 configuration. The wikipedia entry is my latest info and refers to the C2 config of 15,000kg. I understood C2 could carry 40 in the passenger module (SPLM). Clearly all modules would change with a revised config too. Hence a larger SUS could be launched etc.

I remember reading REL say that they do not want to release any 'D' configuration info until it is finalised. Hence all the info on the website pertains to earlier 'C' revisions. I think they last said D config is well advanced, but they are still finalising some details.

I am hoping Baldusi will see this response and let us know anything more about the 'D4' 20 ton revision?  Do you have any links? Thanks.

Here's my 2 second effort to extrapolate how many might be carried in a Skylon capable of a 20 ton SPLM:

40 x 20/15 = 53 passengers.

Apologies if my figures are awry. I am working from memory!

The figures are mostly from papers submitted at the 60th International Astronautical Congress in '09 although the SUS performance is from the User manual  but they're all based on the C2 config with a 15mt payload.
The SUS has a 950kg dry mass, a 7000kg propellant capacity and can deliver a 8.25mt payload to GTO. That's about 15mt all up.
The SPLM has a mass of 7800 kg but the Skylon can only take around 11mt to the ISS so leaves 3mt of people or cargo to that destination, a lower orbit could mean more people. However the payload bay hasn't gotten substantially bigger and the SPLM as designed is already 9.5m long with internal space for 24 seats (not including the pilots) if you take out all the storage racks. I'm not sure how you'd lay it out for more people unless you can some how do without the SOFI (which takes up 3 metres of bay), and make it longer, and I'm not sure you can.
I've not read anything about a D4 config, the last paper I read on Skylon progress was from October and still called it D1. However the new Sabre 4 cycle is meant to be a vast improvement and combined with expansion deflection nozzles and the good news on the reentry modelling it could be that the latest mass estimates have come down while the performance has gone up.
 However it should be remembered that customers can put whatever payload they want in a Skylon, if there's a better passenger module or upper stage, or docking interconnect, for their needs then they can pay for it.

[flymetothemoon]

Ok. I'll take your word for the figures. My point was to emphasise Baldusi's point that they are on to D4 now. I have also read that Sabre 4 is a very big improvement. Looking forward to hearing more concrete details about both.

Indeed. Weight notwithstanding, first, business and cattle class are possbilities   Would depend on the requirements. LEO Joyride (or trip to the other side of the world) or longer mission to the ISS etc.

The provisional passenger module is designed to be re-configurable like an aircraft cabin. There are even doors in the skylon shell to allow conventional entry with an airbridge. The fixed features are the docking port and inevitably the toilet! This page shows numerous configurations including a suggested passenger module with the 40 seats I was referring to:

http://www.reactionengines.co.uk/skylon_pax.html

[simonbp]

XCOR plans to do 100 flights before taking paying customers, as well.

And to note, Xcor once did 7 flights of the rocket-powered Velocity in one day, just because they could.

Skylon is a bit of a different beast, as it requires fancier fuel (LH2, from a fueling station built into the runway) and more delicate payload handling (deployable sats vs. bolted on instruments). So, for purely technical reasons, an individual Skylon won't fly as often as an individual Lynx. But even if they can do the test program at about 3 flights per week per vehicle on 2 vehicles, that's still about 300 flights per year.

[lkm]

Ok. I'll take your word for the figures. My point was to emphasise Baldusi's point that they are on to D4 now. I have also read that Sabre 4 is a very big improvement. Looking forward to hearing more concrete details about both.

Indeed. Weight notwithstanding, first, business and cattle class are possbilities   Would depend on the requirements. LEO Joyride (or trip to the other side of the world) or longer mission to the ISS etc.

The provisional passenger module is designed to be re-configurable like an aircraft cabin. There are even doors in the skylon shell to allow conventional entry with an airbridge. The fixed features are the docking port and inevitably the toilet! This page shows numerous configurations including a suggested passenger module with the 40 seats I was referring to:

http://www.reactionengines.co.uk/skylon_pax.html

You're right, a full length passenger module would be possible and would seat 40 plus a pilot. A cabin bay is 1.75m so there should be room for two more, or 16 people, in a 13m module. Assuming the galley, toilet and rear exit could be successfully rearranged.
The module though would probably mass around  10.5mt, at a guess, so it would be much more limited to the orbits it could reach and would probably best be met by a  OTV shuttle to ferry people to their destination.

[flymetothemoon]

Great interview with Alan Bond I have just come across. Nice coverage of the history of his involvement from the 70s onward, the collaboration of British Aerospace and Rolls Royce on the Hotol project and where we have got to.

Don't know how old this is, but it is new to me anyway.

<a href="http://www.youtube.com/v/LYos3J_8D5Q&rel=1" target="_blank">http://www.youtube.com/v/LYos3J_8D5Q&rel=1</a>

[mrflora]

What we need of course is cheap access to space (CATS).  This presupposes economic access to space (EATS).  This will in turn lead to reliable access to space (RATS).  So, combined, we have as our new acronym:

                        CATS EATS RATS

Regards,
M.R.F.