Skylon

[MG23]

Originally Posted by msbbarratt

Getting every component exactly right every time is a ferociously expensive business.

Except they don't. As evidence we have two shuttles lost in only ~130 launches, and infamous process errors like the tool left in the engine bay even though three people had signed paperwork to verify that it had been removed.

I'm far from convinced that efforts like Space X can make truly large cost savings in the satellite launching business.

In the long run, the only way to make flight to orbit cheap is to make the launchers reusable with minimal servicing. The question is whether you start with something that isn't reusable (SpaceX), and work up, or start by trying to build something that is reusable from the first launch (Skylon).

Skylon's problem is that, like all current single-stage-to-orbit-designs, the payload is small, it could easily become negative as the vehicle mass grows during development, and you have to invest billions of pounds up front before you can find out whether it's possible.

[TURIN]

Except they don't. As evidence we have two shuttles lost in only ~130 launches, and infamous process errors like the tool left in the engine bay even though three people had signed paperwork to verify that it had been removed.

One was lost due to a design fault (o-ring) albeit being operated outside its temperature limits. The other was lost due to FOD.

Dangerous business, space travel.

[MG23]

Originally Posted by TURIN

One was lost due to a design fault (o-ring) albeit being operated outside its temperature limits. The other was lost due to FOD.

If you count a piece falling off the vehicle as 'foreign object damage', yes.

[unmanned_droid]

Yep, anything that falls off a vehicle becomes FOD.

[MAINJAFAD]

Britain's history in the space business is accidentally quite good.

We had a rocket, called it Blue Streak, meant if for use as an ICBM / deterrent but then realised it was obsolete before it ever came anywhere near going into service. Apparently we gave the whole lot to the French as a "please let us in the EEC" bribe. The French said merci beaucoup, pizouf, and now they have Ariannespace.

Disaster? Big opportunity missed? Perhaps, but not as big as all that.

I don't think anyone has ever made a lot of commercial cash running a launcher. Mainly the motivation is to get a capability for national security reasons. Ariane did that for the French, we did that another way.

Instead we concentrated on satellite building. There's the sites in Portsmouth, Stevenage, Guildford, bits 'n' pieces at the Rutherford Appleton labs, etc. Building satellites has proved to be highly profitable.

If Skylon ever gets anywhere, we (the UK taxpayer) have a stake in it. Sending up lots of payloads that can then be in-orbit assembled is ultimately more impressive than trying to launch all in one go (e.g. the International Space Station). "Impressive" can turn into big money, maybe.

Yes we did have an IRBM called Blue Streak which was in fact based on design concept of Atlas and was powered by two Rolls Royce RZ2 engines based on the Rocketdyne S3D used on the US Jupiter IRBM. It was cancelled in 1960 due to the vulnerability of the system caused by the loading time of its LOX / Kerosene propellant. Though the UK had an option of building their own launcher out of it by mixing the deHavilland built rocket with the Black Knight research rocket built by SARO. The Tory government at the time pushed for a European programme which resulted in the European Launcher Development Organisation (EDLO) with the French and Germans providing the second and third stages and the Italians the front end (payload and shroud). There wasn't that much tech transfer at all (had there been the thing may have been successful), the French stage was very the agricultural in its design and used hypergolic propellant, while the Germans had massive problems in getting their hypergolic fuelled stage light enough and powerful enough to get the payload into orbit (plus the fact they were starting from scratch seeing all of their best people were in the US or East Germany). The testing regime was very step by step. Blue Streak on its own 3 times out of Woomera (the first flight was actually a failure as the rocket went out of control a number of seconds before scheduled shut down), plus 2 flights with dummy stages, the first of which was blown up by the range safety officer due to incorrect data from a tracking radar. the other three flights were successful. The next two flights had a live French stage which failed both times. After this, the live German stage was added and after the British and French stages had successfully lofted it to altitude, only for it to explode on ignition on the first attempt and fail to fire at all on the second. The final flight out of Woomera saw all three stages successfully operate, only for the Italian payload shroud to fail to separate which resulted in the satellite and the rest failing into the Indian Ocean. The final flight was from Kourou of an improved Europa II fitted with a solid propellant French forth stage. This failed due to somebody cross-wiring part of the guidance system. At this point the UK pulled out of the launcher program as it was discovered that Europa wasn't capable of putting a large enough payload into Geostationary orbit, plus the fact that there wasn't the money to do both Launchers and Satellites. So Mr Benn (the man in charge at the time), picked the satellite option, which has been very successful. The French then went the LOX / H2 propellant direction and produced the successful Ariane which is a very different beast in all regards to Blue Streak. (Plus having a launch site on the equator is very handy for putting up Comms sats as it allows heavier payloads to be lofted than from places like KSC for the same amount of propellant).

[t43562]

Having read a lot of the blurb and seen the talks too, my understanding is that there's no point creating an engine without having a feasible concept spaceplane to stick it on otherwise how would you know what the engine should look like, how big it should be, whether it could actually get something into space?

Did Mr Whittle have a similar point of view?

I don't know but he probably had at least some idea of what his engine would be required for. Whether it would fly fast or high or for long or may not have been all that critical as long as it could make something fly at all.

SABRE has to get a vehicle into space with enough payload to matter and that is a much more demanding requirement. Already they have gone through 4 engine designs because their models using Skylon showed them what the trade-offs would be. If one used a significantly different vehicle then I presume that some of those trade-offs would change and force yet another design to be done.

They have certainly made statements in the past about it being difficult to scale down the engines without making them uneconomic. I don't know if that's still valid but it's the reason they have given for not making a smaller vehicle to test the whole concept.

[Onceapilot]

So, a closed cycle helium expansion turbine to drive a 450,000 lb thrust air breathing axial compressor. Get real. It wouldn't work efficiently in a power station, only on paper as a theory.

OAP

[Torquelink]

BAE as an investor? Given their apparent total aversion to anything that involves commercial risk rather than guaranteed government cost+ business, I'm not sure they'll be much help to RE. They milked their civil aircraft portfolio as far as they could on minimal investment and then closed them down, flogged their share in Airbus etc. The only way BAE will help get Sabre in the air is if its attached to yet another minimal makeover of the 748/ATP or 146/RJ . . .

[Tourist]

Originally Posted by Torquelink

BAE as an investor? Given their apparent total aversion to anything that involves commercial risk rather than guaranteed government cost+ business, I'm not sure they'll be much help to RE.

That makes no sense.

If BAe don't take risks, then surely the fact that they have just invested millions in the company means they don't think it is a risk?

You can't have it both ways.

Onceapilot

NASA, ESA and BAe all think you are wrong.

I'm willing to believe that you are a Nobel prize winning rocket scientist that knows better than them......

.....oh no, wait.


It is easy to sit back with no expertise and say "it'll never work" about all new inventions, and 90% of the time you will be right and can act smug, but it doesn't make you a decent human being.
If it weren't for those willing to strive and push the boundaries, we we would still be wearing hides.

[Onceapilot]

Tourist,
I can understand that the headline grabing concept is being used as a political means to invest some money in the spinoff R&D for other British developments. But, to suggest that the concept, as shown in their blurb, is practical surely hinges upon the adequate supply of Dilithium crystals from China which, too me, seems far-fetched.

OAP

[Torquelink]

That makes no sense.

If BAe don't take risks, then surely the fact that they have just invested millions in the company means they don't think it is a risk?

You can't have it both ways

Tourist - that's actually a good point and I was being (slightly) facetious which you probably have guessed from my suggestion of using warmed-over 748/ATP as the launch vehicle.

However, based on their track record to date, BAE will be betting on the ESA partner nations eventually stumping up funds to complete the project: both for the airframe and the engines. The amount they've invested is pin money compared to the total required but they see a reasonable chance of a government-cushioned pay-off as in virtually all the projects in which they invest. SpaceX they're not.

[Lyneham Lad]

ANALYSIS: British spaceplane engine concept gets cash boost

An interesting and quite upbeat article on Flight Global.

[t43562]

US Military Set to Unveil Concepts Based on Skylon Space Plane Tech

Within the next year, the U.S. Air Force plans to unveil novel spacecraft concepts that would be powered by a potentially revolutionary reusable engine designed for a private space plane.
Since January 2014, the Air Force Research Laboratory (AFRL) has been developing hypersonic vehicle concepts that use the Synergetic Air-Breathing Rocket Engine (SABRE), which was invented by England-based Reaction Engines Ltd. and would propel the company's Skylon space plane.
....


The key SABRE technologies that AFRL, based in Ohio, will start work on later this year, and possibly fly in the future, are related to the engine's precooler. This device precools the air entering the engine at speeds greater than four times the speed of sound (Mach 4). SABRE's precooler will cool such air from more than 1,832 degrees Fahrenheit (1,000 degrees Celsius) down to minus 238 F (minus 150 C) in one one-hundredth of a second. The oxygen in the chilled air will become liquid in the process.

[tartare]

Originally Posted by t43562

US Military Set to Unveil Concepts Based on Skylon Space Plane Tech

Really?
Fantastic if true - but wouldn't one want to keep this as an SCI programme?
If I interpret this article correctly it is hinting at designs for a USAF single stage to orbit spaceplane.
If it's really happening - wouldn't this be blackest of black?

[MAINJAFAD]

If it's really happening - wouldn't this be blackest of black?

The X-30 wasn't a black program and this is basically the same.[/quote]

[t43562]

This is an example from BAE - it seems that it might be related to the work on the SABRE engine.

[t43562]

Basically Reaction Engines have been able to unlock the 60M that the government wanted to give them without it being "unfair state aid".

They have scaled down their demonstrator so that it won't cost as much.

Also they are looking at co-operating with Orbital Sciences to build air-launched vehicles which could test their engine.

ESA commits to next stage of UK revolutionary rocket engine / Space Engineering & Technology / Our Activities / ESA

Funding flows for UK?s ?revolutionary? Sabre rocket engine - BBC News

Reaction Engines Ltd - News: 12 July 2016

Reaction Engines Ltd - News: 11 July 2016

[Onceapilot]

Reusable/semi-reusable solid or liquid hydrogen + oxygen boosters will remain the cheapest payload to orbit, this side of the discovery of dilitiumn crystals.

OAP

[Willard Whyte]

Go back to your cave painting oap.

[tartare]

Just once in my lifetime I'd like to see a really exponential aerospace breakthrough.
Maybe this will be it.
Fifty years old; so just maybe I might get to ride on a Sabre powered hypersonic airliner in my 80s.
Or even less ambitious, perhaps a seat in cattle class on a blended wing body powered by some 200,000lb turbofan that uses less fuel than a VW Golf (I'm joking...)
A battery with energy density exceeding that of Jet A1?
Saw the rise of the Internet, the evolution of mobile phones, GPS... here's hoping...