Re: How big would an SSTO be?

On 5 Jul, 06:59, Sylvia Else <syl...@xxxxxxxxxxxxxxxxxxx> wrote:
You may also be interested in these patents (in the name of Alan Bond)

<http://www.freepatentsonline.com/result.html?p=1&query_txt=IN%2F%22Bo...>

though you need to signup (free and not overly intrusive) to get the PDF
versions of the documents with diagrams.

The patents include what I take to be details of the SABRE heat
exchanger and how they avoid clogging with frost (which on their web
site they claim to have successfully tested).

Thank you very much.
I rather suspect that patent 5101622 is the patent for the original
RB545 that was going to power HOTOL, and which was made sercret under
the UK's Official Secrets Act. Note that the patent is assigned to Rolls
Royce.

Are Rolls Royce actively using their patent. A patent can be
challenged if it is not being used. How do you prove it is not being
used. Well Rolls Royce will have to sue you and present their
evidence.

One thing about the secret world. It abandones things but it still
does not want anyone else to have them!

Yes quite. I must say your references answered my immediate questions.
My personal feelings are that at hypersonic speed the engines have to
be at least blended in with the airframe even if they are distinct
from it. This is because hypersonic speed per se causes a lot of
compression. To get the optimum compression ratio the siting of
engines is extremely important.

Skylon's engine position seems to be dictated by the centre of gravity
considerations that plagued HOTOL. This seems to preclude them being
integrated into airframe.

Interesting. I said previously that I thought a small aircraft was
what was indicated. If the LOX were to be present at take off it could
be used for balance, enabling you to put the engines where you wanted
to for other reasons.

Also if you were to use more modern materials to make the engines
lighter that would help. SSTO means that with the large fuwel loads
deadweight must be as low as possible.

Again whatever the configuration the trailing edge represents tha last
"turbine rotor" and thrust is actually provided by the trailing edge.
If you have actual engines they are engines which (in effect) have the
front compressor and rear turbine removed as the pressure in the
airlow is doing that for you.

Of course you will need engines to traverse the subsonic and low
supersonic régimes.

I have a number of questions for ESTEC. The reference talks about
turbulence and mixing. Very important. Will hydrogen burn in time if
injected into a hypersonic flow? I presume that is the fuel. My
question to ESTEC :-

One of the attractive things about the SABRE engine is that, as I
understand it, the airflow in the core of the engine is subsonic. This
together with the fact that the engine will operate at low speed means
that a lot of the development testing can be done on the ground.

Yes but you will need a computer simulation to prove all flight
régimes. The performance of the whole airframe being of such great
importance at hypersonic speed.

Also you do not have an either/or. You can have injectors which cut in
as speed increases. If these were under active control overall
performance, including the airflow to the sabre engine could be quite
finely adjusted.

Also at subsonic speed stall could be delayed.


Aurora and the ESTEC project are working on the same Physics. They
must have reached very similar conclusions. As far as "hypersonic air
breathing aircraft have never worked" is concerned, I think it is
clear thast we have materials and technology now that was not
available in the past. Whether this is enough I don't know. A
judgement can only be made with proper peer reviewed papers - not from
anecdotal evidence about Aurora, which may be a *** eyed project
anyway.

It's a strange argument anyway. As if one should never try to do
something that other people have failed to do.

I'm sorry if I gave that impression. I did not mean to. What I meant
to say was that there were secret programs with patch success.

http://www.abovetopsecret.com/pages/aurora.html
http://en.wikipedia.org/wiki/Aurora_aircraft

We don't know why Aurora was discontinued. It might simply be that it
did not make military sense flying at high altitude and not being
manoeverable. It could be shot down with a laser mounted in a Boeing
747.

Anyway Aurora has flown. Eyewitnesses talk about a ball of fire.
(Sounds like ET. My postings on ET were in part designed to get us to
focus on the real secret world. Aurora has external combustion from
the leading edge, probably uses methane (if hydrogen it would be a
pale blue flame). The drawing with the fusilage covered with engines
cannot be right as where does the fuel go?

I do not like the secret world, I abhor its methods, particularly its
methods of denigration and I do not believe it to be terribly
efficient. Will you succeed? I don't know, a success is always
preceeded by failures. What it does prove is that you will have to be
open to new ideas, explore every nook and cranny, particularly
turbulent airflow control.

BTW - The 2STO proposed by all the (knowledgeable?) people does not
work either.

http://www.freerepublic.com/focus/f-news/1590674/posts

- Ian Parker

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