guys, did you see the design for an airbreathing nuclear rocket reported by nextbigfuture? I know that it's just summer speculation, but I was wondering whether an integrated design with the SABRE is, as a pure matter of principle, possible. http://nextbigfuture.com/2015/07/nuclear-thermal-turbo-rocket-with.html
The Aviationweek article is now generally available. I suppose the idea is that subscribers get it early but the public gets it eventually.Here's the link again:http://aviationweek.com/technology/air-breathing-sabre-concept-gains-credibility?NL=AW-05&Issue=AW-05_20150730_AW-05_233&sfvc4enews=42&cl=article_1&utm_rid=CPEN1000001204273&utm_campaign=3312&utm_medium=email&elq2=de275daceef84b74b5541bcb84290e12
That is a statement based on bias and not supported by any relevant data. Not all gov't contracts are cost plus.
Fairly simple the military will always get first dibs on something like this once they are persuaded it works and does what it says on the can.
The commercial sector is often more risk adverse and though the military can be conservative in these things as well, if they are persuaded they are far more likely to put money into something like this.
"The question to answer next is what benefit the Sabre could bring to high-speed aerospace vehicles compared to other propulsion systems,” “AFRL is analyzing vehicle designs based on the Sabre engine concept. We are also considering testing their heat-exchanger technology at Mach 5 flight conditions in a high-temperature wind tunnel.”
“very risky as a first application,”“Sabre may provide some unique advantages in more manageable two-stage-to-orbit configurations.”
“From our perspective there is no cheap, quick way around the problem of space access. We’ve done studies and we agree that [a] sensible second-stage approach might be best to demonstrate the technology by taking it one step at a time,”
“Enough people now say the Sabre cycle works and it looks compelling. Now the question is what will we do with it?“ As an engine class, it straddles both air and space, so we have to optimize a system to take advantage of that for a given application. As we structure the development plan going forward, we can figure out what the first use is going to be. So over the next six months we will be closing in on that application.”“Right now we are in the process of scoping that demonstration engine in terms of what it needs to achieve,” “The key thing is to tick the boxes in every area it needs to tick. It is all about making sure the demonstrator meets the performance requirements that are set for it. We want to make sure it really works and offers the sort of performance that we say it can do. We’re still in that phase. The studies are in their infancy for the engine demonstrator but we have got to make sure we’re not biting off too much more than we can chew.”
“because the engine uses the atmosphere as the source of its energy and the reaction mass. And because of the clever heat-exchanger technology, we can modulate the air so the turbomachinery in the engine doesn’t know it is on the ground.”
LM have the SR-72 concept which is looking for a pair of engines. The thing is these prototype programs can often end up black budget items where it's hard to see what's happening with them.
Quote from: Star One on 07/30/2015 05:43 pmLM have the SR-72 concept which is looking for a pair of engines. The thing is these prototype programs can often end up black budget items where it's hard to see what's happening with them.No they are not. They have partnered with Aerojet Rocketdyne for a turbo ram/SCRamjet engine. LM think they already have an engine for their concept (and it's nowhere near cutting metal at this point).
Welcome to the forum livingjw.. I see you've taken Jon Goff's advice on learning about things on the Internet.
Skylon is:Quote“very risky as a first application,”“Sabre may provide some unique advantages in more manageable two-stage-to-orbit configurations.”(Hellman, AFRL)
(Sam Hutchison, Reaction Engines)Quote“Enough people now say the Sabre cycle works and it looks compelling. Now the question is what will we do with it?“ As an engine class, it straddles both air and space, so we have to optimize a system to take advantage of that for a given application. As we structure the development plan going forward, we can figure out what the first use is going to be. So over the next six months we will be closing in on that application.”“Right now we are in the process of scoping that demonstration engine in terms of what it needs to achieve,” “The key thing is to tick the boxes in every area it needs to tick. It is all about making sure the demonstrator meets the performance requirements that are set for it. We want to make sure it really works and offers the sort of performance that we say it can do. We’re still in that phase. The studies are in their infancy for the engine demonstrator but we have got to make sure we’re not biting off too much more than we can chew.” (Hutchison)
Apparently the demonstrator is on track to do a full engine test in 2018/2019.Ground testing is possible :Quote“because the engine uses the atmosphere as the source of its energy and the reaction mass. And because of the clever heat-exchanger technology, we can modulate the air so the turbomachinery in the engine doesn’t know it is on the ground.” (Hutchison) They plan to simulate higher velocity air by raising the temperature of the air entering the inlet. They are also going to do wind tunnel tests with the inlet.The AFRL suggest that they might do Mach 5 tests in a high temperature wind tunnel. There are apparently no short term funding shortfalls.
Sam Hutchison**As we structure the development plan going forward, we can figure out what the first use is going to be.**That sounds like a really odd thing for someone from REL to say. Was he thinking one thing and said another. I thought they knew what the first use of the SABRE was going to be. I thought they had designed it from the start to be an SSTO. Nothing else. Not a sub-orbital whatever, or a high-Mach quick reaction craft for USAF. wtf?
Quote from: t43562 on 07/30/2015 04:58 pmSkylon is:Quote“very risky as a first application,”“Sabre may provide some unique advantages in more manageable two-stage-to-orbit configurations.”(Hellman, AFRL)SABRE is designed to do one job. Get the vehicle it's attached to from a standing start on a runway to Low Earth Orbit.If they didn't want that they should have said so and asked either for a hypersonic cruise engine like LAPCAT (which is very different internally) or the HX technology to put on the front of a turbofan.It seems they either didn't realize how closely this is tied into the use of LH2 or they didn't really believe it could work at all. Unfortunately now they've run the analysis themselves they now realize it can, and they're not sure what to do about it.
As we structure the development plan going forward, we can figure out what the first use is going to be. So over the next six months we will be closing in on that application.”“Right now we are in the process of scoping that demonstration engine in terms of what it needs to achieve,” ly hope those matters stay within REL.
I'm confident you're reading too much into this. It would be a different matter if Alan Bond said "we're switching to TSTO" publicly, but here you have their Director of Corporate Development sound just exactly like someone in that role should: he's being broadly supportive of the AFRL statement - i.e. their recent partner who they may hope to work with again (read $$$$ that could help further the Skylon project).
Quote from: adrianwyard on 07/31/2015 08:56 pmI'm confident you're reading too much into this. It would be a different matter if Alan Bond said "we're switching to TSTO" publicly, but here you have their Director of Corporate Development sound just exactly like someone in that role should: he's being broadly supportive of the AFRL statement - i.e. their recent partner who they may hope to work with again (read $$$$ that could help further the Skylon project).How would we know there not still actively working with the USAF, it may not be something the USAF wish broadcasting.I personally feel if the USAF want a hypersonic vehicle of some type then REL are their best best to achieve this.
